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Drag Racing Discussions => Front Engine Dragsters => Topic started by: crider on July 18, 2018, 03:19:07 AM

Title: calming the car down on the starting line
Post by: crider on July 18, 2018, 03:19:07 AM
Finally got the car out for the first time this year, and picked up right where it left off last fall. It 's 178" David Beard chassis with a 604" BBC. I had made around 30 runs with the new engine last year and ran straight as a string but not performing up to potential. I finally tried pulling the timing back to 32 degrees and the engine seems to love it, but it has made the car for the most part undrivable. I've tried both raising and lowering the wheelie bar but it just hits the bars hard and gets loose. I'm running 33-10.50 tires and a 4.20 gear. Right now I'm thinking either a gear swap or a front weight bar. What would be the right thing to try first?
Title: Re: calming the car down on the starting line
Post by: fuel749 on July 18, 2018, 05:46:38 AM
While I was at the track that day I might have gone back to the original setup just to see if it would get off the starting line.  What were the incrementals when it got down the track?  Injected or carbureted?  Leaving at idle or off the trans brake?  When you say not performing up to potential, what are you expecting from it?  It sounds like its dead hooking
Title: Re: calming the car down on the starting line
Post by: retroboy on July 18, 2018, 05:53:37 AM
Interesting to see that three of the last five posts are about start line and rear gears. I have a similar problem with the car being something I have to fight off the start line. I put weight on the nose which helped a little bit but I going from 4.3 to 3.89 rear gears hoping that helps. I have a 3 SPD with a 2.45 first gear and a 31" tyre.
Title: Re: calming the car down on the starting line
Post by: rooman on July 18, 2018, 06:03:58 AM
How far out is the motor?  How long is the wheelie bar and how rigid? ?  'glide with 1.76 or 1.82?  Does it jerk the front end and then get loose with the bar up? Does it spin at the step with the bar down?

Roo
Title: Re: calming the car down on the starting line
Post by: fuel749 on July 18, 2018, 07:43:33 AM
I'm thinking I built that with the motor 42" out but I originally built it for someone else so I could be wrong. I only build them with the motor further back by customer request.  If I built the bar it's probably between 48"-60" with enough give to not unload or shock the chassis unless things are going bad fast.

Jim, when you say the wheelie bar was low how low was it.  On our small block altered  (4.56, 33x10.5W, 1.76 low, probably 450 horse) I run the wheel almost touching the ground to unload the tires and generate wheel speed.  On occasion the owner/driver gets a hair across his ass for some big wheelie pictures so I put the bar up and it wacks the bar hard enough to unload the tires and send him for a ride. 
Title: Re: calming the car down on the starting line
Post by: dusterdave173 on July 18, 2018, 11:51:07 AM
I'm thinking I built that with the motor 42" out but I originally built it for someone else so I could be wrong. I only build them with the motor further back by customer request.  If I built the bar it's probably between 48"-60" with enough give to not unload or shock the chassis unless things are going bad fast.

Jim, when you say the wheelie bar was low how low was it.  On our small block altered  (4.56, 33x10.5W, 1.76 low, probably 450 horse) I run the wheel almost touching the ground to unload the tires and generate wheel speed.  On occasion the owner/driver gets a hair across his ass for some big wheelie pictures so I put the bar up and it wacks the bar hard enough to unload the tires and send him for a ride.


I agree that wheel a couple inches off the ground with driver in the car is all my car wants--higher and it is a wild ride
38 lbs on the nose in a 200 in car with maybe 425 HP  Get wheelie bar where you can just get your shoe tip under it
Leave from idle on footbrake and just see   Any RPM and it is going to be wild for sure with that much engine

Title: Re: calming the car down on the starting line
Post by: wideopen231 on July 18, 2018, 12:22:41 PM
 Can not say how well it works yet, I set my car up with motor 50" out,fuel tank and battery on nose.I also went with 1.60 low and 4.10 rear gear trying t make it soft at hit. I am wondering about tire size with that much motor. Since can not read op and most reply at same time I am thinking you said 10.5 tire? why not at least 12" and maybe taller to ease up on hit. Anything that can pull timing and ramp it back in? Besides old TA/FC IHRA racer should be use to not going straight. LOL
Title: Re: calming the car down on the starting line
Post by: wideopen231 on July 18, 2018, 12:26:24 PM
Maybe before adjusting timing it was spinning some and made car more driveable. Go back to square one.iF that works you might look at tire pressure if adjusting timing back down.Just like with your old TA/FC a little spin can be good if its controlled.
Title: Re: calming the car down on the starting line
Post by: crider on July 18, 2018, 03:25:00 PM
To answer some of the questions. It's a glide, 1.76 gear. Leaving off the brake at 4500. 6200 converter. I've tried the rear bar from as low as 1.5" off the ground up to about 5". up. With the bar at it's lowest, it was quick yank up on the front end then instant spin and hard left turn. With the bars up about 4" it's still came up hard, but I was able to ride for 60ft or so before things unloaded and more bad spin. It's was running 5.40's before the timing change. Car should be easily capable of 5.00's or a little better. The one pass I was able to pedal it and get down the track under power it went 5.35 so it would appear that the timing change has helped the hp, if I can just figure out the right combo on the car. I like a car that takes a little skill to drive, but I also like to be able to make it all the way down the track too
Title: Re: calming the car down on the starting line
Post by: wideopen231 on July 18, 2018, 03:38:39 PM
what where last years runs like? Any other changes other than timing? With 604"BBC I think you have low expectations. Maybe way off but I would think you should get well below 5.0's once you get it tuned out. I have had situation where tuning soft just screwed everything and had opposite where I backed it down and it hauled butt. If only change is timing I wold backup and punt. Then I am also rooking at tuning a FED so my 2 cent maybe over valued. If that don't work and you don't have a retard capable system then I would go after fuel. Richen it and lean it shortly into run. Electric solenoid would be best and use rpm switch or timer if have delay box.
Title: Re: calming the car down on the starting line
Post by: crider on July 18, 2018, 03:59:22 PM
last years runs were low 50's high 40's. Timing was only change. I made the change before the last run I tried to make last fall. Haven't made a clean pass since the change. But also have only had the chance to get it to the track once since then either. I'm still on a carb, so jetting is about all the fuel tuning I can do right now. My hilborn setup is at spuds place as we speak. I think the 5.0-4.90 expectation is pretty close for the topend I have right now. The heads are only flowing just over 400 at 700 lift. Too small for this motor I think. I wasn't planning on going this big, but a great deal on a high dollar crankshaft came along right after I had bought the new block, so here I am. The heads and cam were off the old 526 that the block died on before ever getting a full pass
Title: Re: calming the car down on the starting line
Post by: hemidakota on July 18, 2018, 06:43:04 PM
What air pressure in slicks?
Title: Re: calming the car down on the starting line
Post by: wideopen231 on July 19, 2018, 03:05:03 AM
After reading your OP i realized not answered question. I would do weight bar first. I have noticed most guys have added weight to front to make car work.Although sacreligious  to add weight its faster than sideways and /or lifting off throttle. Also cheaper than gear swap and easier to change if need.
Title: Re: calming the car down on the starting line
Post by: crider on July 19, 2018, 03:15:29 AM
Hemi Dakota, I had 7.5 lbs in them. I would have tried adding a pound or 2 but had forgot the air tank at home
Title: Re: calming the car down on the starting line
Post by: PSweeney on July 19, 2018, 03:29:33 AM
I think theres 3 aspects.  Weight, tire pressure and the bar height.  Get the nose weight and tyre pressures balanced so it doesn't dead hook and you get some wheel speed so it reduces the shock load on the bar / tires, then set the bar to just above the tire squat height, about 2" assuming the weight/tire pressure ratio is right.
Title: Re: calming the car down on the starting line
Post by: hotrod316 on July 19, 2018, 07:25:27 AM
converter?   ???
Title: Re: calming the car down on the starting line
Post by: afaulk on July 19, 2018, 03:37:52 PM
I have a home built chassis. Its 185", 4.30 gear, 1.69 low in trans, 33x10.5w, 370" Blown SBC, about 900 hp. 9", 5500 converter. We made a couple of test hits on the new chassis last fall and the car wanted to go right. This spring we made about 4 more test hits figuring out what it wanted. First I added 40 lbs to the nose (battery and fuel tank are up front also). Car was still going right at the hit. I raised the bar from 3" to 4.5" and added another 40 lbs to the nose. (the bar is about 66") the last three passes have been 4.90, and 4.80 with 1.09 sixty ft  and 4.75 with 1.08 sixty ft, leaving off idle and shifting at 6200. Oh and 7 psi in the slicks.      It sounds like your car is doing the same as mine did before adding the weight. Dont be afraid to add a weight bar. You've got to keep the front end down and you've got to get it up on the tire. Good luck! PS. Not sure how much faster I want to go...…..
Title: Re: calming the car down on the starting line
Post by: hemidakota on July 20, 2018, 06:30:05 PM
Hemi Dakota, I had 7.5 lbs in them. I would have tried adding a pound or 2 but had forgot the air tank at home

The Dragster I have worked on and driven for years is a 185" mild steel fed. 565 bbc injected alky. We had to run 5 to 5.5 psi in the slicks with bar at about 2" to make it work and yes 33 x 10.5 m/t slicks. I am no pro but the higher pressures on a well prepped track killed us every time FWIW. 6200 converter also. It would 1.13 to 1.15 in 60'.
Title: Re: calming the car down on the starting line
Post by: crider on July 21, 2018, 03:46:18 PM
Ok. Seems like some good suggestions here to try. Weather permitting I'm going to try to take it back to the track Friday night and play around with the timing and air pressure. I think I might try a lower launch rpm at some point too. If this doesn't work, who is a good source for a weight bar for the front axle?
Title: Re: calming the car down on the starting line
Post by: fuel749 on July 22, 2018, 05:48:58 AM
You could check with the guy that built your car if you're in need of a weight bar
Title: Re: calming the car down on the starting line
Post by: wideopen231 on July 22, 2018, 11:39:58 AM
Good luck and lets us know how it goes,straight hopefully.Well mostly straight,got have some reason for all the added weight in seat to be riding along.LOL

Title: Re: calming the car down on the starting line
Post by: masracingtd1167 on July 22, 2018, 01:23:56 PM
A couple of things you should check are the roll out of your tires ! No more than half an inch ! Have you checked your wheelie bar to see if it is straight ! The car should go straight even if the front wheels are in the air !Hope this helps you !
Title: Re: calming the car down on the starting line
Post by: dusterdave173 on July 22, 2018, 02:26:53 PM
We went through a spell where car would go left, maybe go right etc  Rollout was perfect wheelie bar centered But we discovered that the holes for wheelie bar adjustment pin were too sloppy--This tiny amount of slop allowed the wheel to tilt ever so slightly when it hit the pavement so sometimes straight sometimes right or left---the amount of slop in the entire setup was so small but when we precision re-drilled the holes and added a washer here or there --got the wheelie bar dead rigid it solved our issues 
We also never center it from the tires--we always pull wheel and go from edge of brake rotor or axle flange and make it dead on centered

Low launch RPM helped our car out a ton as well
Title: Re: calming the car down on the starting line
Post by: wideopen231 on July 27, 2018, 09:14:04 AM
So what happened with car?
Title: Re: calming the car down on the starting line
Post by: crider on July 28, 2018, 07:25:23 AM
I made it out to the track last night, Car was still not going straight but at least it was predictable. It was carrying the front wheels and drifting to the right. Kept working with the tire pressure and wheelie bar and it was getting better. Last pass something crapped out in the ignition, and it lost a lot of power but it went straight. Not sure if I finally had it lined out or if it due to the loss of hp though. Guess I'll give it another shot in a week or two 
Title: Re: calming the car down on the starting line
Post by: Curly1 on July 30, 2018, 10:03:26 AM
I made it out to the track last night, Car was still not going straight but at least it was predictable. It was carrying the front wheels and drifting to the right. Kept working with the tire pressure and wheelie bar and it was getting better. Last pass something crapped out in the ignition, and it lost a lot of power but it went straight. Not sure if I finally had it lined out or if it due to the loss of hp though. Guess I'll give it another shot in a week or two

So are you putting more air in right rear?
Title: Re: calming the car down on the starting line
Post by: crider on July 31, 2018, 03:19:27 AM
Yes. It seemed to be helping until the MSD box went
Title: Re: calming the car down on the starting line
Post by: JrFuel Hayden on August 01, 2018, 11:41:32 AM
I agree, add at least 20 lbs to the nose, because the front is slaming up, hitting the WB and unloading the slicks. If you set the WB around 1 1/2-2" a flxable WB should more gently push the fron down. But you may discover you need to add more weight to the nose. That's all about the engine location, you could run less nose weight if you motor was out 46" +. Back in the day TF cars ran the motors out 36" BUT that was before VHT, and they smoked the tires, ie before slipper clutches. The trick JrFuel cars are running 48-52" out now in order to keep the tires spinning some, so they don't dead-hook and puul the motor down below your HP rpm range.
We run our JF powerglide with a 1.68 1'st gear to hit the tires softer, plus the trans ratio is closer to the 1 to 1 of hi gear.
The other thing that has helped us on traction is we run a looser converter, [ now 8500-8700, but my next one will be 8900-9000] it hits the tires softer, and allows the engine to get up to the HP rpm.
A good goal for picking the stall is 1000-1500 below your shift point, but best is to send a dyno run to your converter guys , I highely recomment A-1, they have a lot of FED experience and customers. Again JF rules limit us to 12" wide tires, we run 33 & 31 tall tires. we have tried 33x10.5x15 MT tires too running 7+ pressure, mostly because the MT have stiffer sidewalls designed for 10.5 door cars but our best ET's have been with the Goodyear 31x12x15, at around 5 1/2 to 6 lbs.
BTW Hayden wheels are now dealers for Goodyear and M&H slicks.
I hope this helps
Title: Re: calming the car down on the starting line
Post by: wideopen231 on August 02, 2018, 05:38:15 AM
Curious as to why the 10.5 tire? While I understand motor is not a balls to the wall combo,it still should have butt load of TQ and good hp. Not saying wrong( because I know nothing about tuning FED) just wondering why not more tire.  Does not seem to hurting your hooking car up now that I asked question.LOL
Title: Re: calming the car down on the starting line
Post by: Paul New on August 02, 2018, 07:27:50 AM
Curious as to why the 10.5 tire? While I understand motor is not a balls to the wall combo,it still should have butt load of TQ and good hp. Not saying wrong( because I know nothing about tuning FED) just wondering why not more tire.  Does not seem to hurting your hooking car up now that I asked question.LOL

Are you talking about Jon’s car or the original post?  If it Jon’s his car is an all out heads up class car!
Title: Re: calming the car down on the starting line
Post by: wideopen231 on August 02, 2018, 08:52:27 AM
Talking about OP I know Jons car can not run bigger tire.Also pretty sure Jon's is a all out motor with almost nothing left on the table power wise.
Title: Re: calming the car down on the starting line
Post by: tire wiper on August 02, 2018, 12:47:43 PM
Section 5
Junior Fuel Eliminator
DESIGNATION
Class designation (below) preceded by car number. Three classes – front-engine methanol-burning dragsters.
Handicap starts, using .4 Pro Tree. Handicaps based on recognized class records at time of event.
CLASSES
A/ND: 3.50 pounds per cubic inch, 1,300-pound minimum weight (refer to NHRA A/ND rules)
B/ND: 3.50 pounds per cubic inch, 1,300-pound minimum weight. Limited to OEM cast-iron Hemi; 23-degree small-block Chevy, big-block Chevy and Ford may use aftermarket cast-iron cylinder head, but stock valve angles must be retained. Raised runner 23-degree small-block Chevy cast-iron heads permitted (refer to NHRA B/ND rules)
C/ND: 3.50 pounds per cubic inch, 1,350-pound minimum weight. 23-degree Chevy (no raised runner) OEM or aftermarket replacement style, OEM Ford or aftermarket replacement style heads. Other makes fall under same category as above. Plus or minus (+ or -) 3 degrees maximum allowance for milling of heads (refer to NHRA B/ND rules)
TIRES
Maximum width 12 inches as measured across tread surface or indicated by manufacturer on the sidewall. See General Regulations 5:1.
Title: Re: calming the car down on the starting line
Post by: wideopen231 on August 19, 2018, 03:52:36 PM
Any runs lately Crider?
Title: Re: calming the car down on the starting line
Post by: crider on August 22, 2018, 02:37:38 PM
No, between being busy and the lousy weather, I haven't been able to get back out to the track
Title: Re: calming the car down on the starting line
Post by: crider on September 16, 2018, 10:14:39 AM
Well I had a little free time, and with the rainy weather today, it was time to get out in the garage and do a little checking on the dragster. I got it up on stands and stripped the wheels and tin off of it so I could pull a string on the centerline and check where the wheelie bars where hitting. Looks like I was about 1/2 off from center. Any thoughts to if that would be enough to drive the car hard in one direction or another? Also found some slop in one of the upper mounting tabs. It seems the whole had wallowed out, I'm thinking that could have been a part of my problem, letting the bars move. So I drilled it out and welded a hardened insert in the hole. I also checked my tire diameter, they are less than 1/8 different, so shouldn't be any problems there. Anything else I should check while I have the car stripped down? Hoping to take it over to elk creek nostalgia event at the and of the month.
Title: Re: calming the car down on the starting line
Post by: dusterdave173 on September 16, 2018, 04:33:26 PM
That is a mile off  It would have giant  effect--- Glad you discovered it--try for almost zero slop
Title: Re: calming the car down on the starting line
Post by: Curly1 on September 16, 2018, 06:38:50 PM
Please let us know how it works and if it resolves the issue. Good Luck.
Title: Re: calming the car down on the starting line
Post by: jeff/21 on September 17, 2018, 04:18:38 PM
A better way to measure is the circumference
Title: Re: calming the car down on the starting line
Post by: JrFuel Hayden on September 17, 2018, 07:18:08 PM
Yes I agree. check the circumference, at the tire pressure you race at. The dia is too inacurate.
Use a thin tape measure so it bends anough to go around the tire, or a cloth tape measure.

Good Luck.
Jon
Title: Re: calming the car down on the starting line
Post by: wideopen231 on September 19, 2018, 09:11:11 PM
I have not found a seamstress tape long enough but a surveyor tape from Lowes works great. I think you are going to find out the wheelie bars is big part of your problem,but what do I know.
Title: Re: calming the car down on the starting line
Post by: BK on September 19, 2018, 10:24:20 PM
Well I had a little free time, and with the rainy weather today, it was time to get out in the garage and do a little checking on the dragster. I got it up on stands and stripped the wheels and tin off of it so I could pull a string on the centerline and check where the wheelie bars where hitting. Looks like I was about 1/2 off from center. Any thoughts to if that would be enough to drive the car hard in one direction or another? Also found some slop in one of the upper mounting tabs. It seems the whole had wallowed out, I'm thinking that could have been a part of my problem, letting the bars move. So I drilled it out and welded a hardened insert in the hole. I also checked my tire diameter, they are less than 1/8 different, so shouldn't be any problems there. Anything else I should check while I have the car stripped down? Hoping to take it over to elk creek nostalgia event at the and of the month.
When I had two wheels on my bars I would raise the right side about an inch and it would steer the car to the left. When I switched to a single wheel I would but the wheel about in inch to the left and it would steer it left.
So yes having the wheel off center will steer it by shifting weight. Wheel to left weight goes to the right steers left, Wheel to right weight goes left steers right.
Title: Re: calming the car down on the starting line
Post by: crider on October 07, 2018, 04:17:34 AM
Well, I took the car to the nostalgia event at Elk Creek Dragway last weekend. After getting the wheelie bar adjusted to dead center and lowering it back down to 1 3/4" off the ground, the car is at least predictable. The problem is it is turning right about 30 Ft out. I've tried adding air to the right tire and seemed to just make it worse. Can't figure out what is going on with this car. It used to go straight as a string, this summer I have only managed to make one pass that I didn't have to get out of it to keep it in the lane
Title: Re: calming the car down on the starting line
Post by: masracingtd1167 on October 07, 2018, 07:48:35 AM
Sounds like you are making more power with the timing change ! If you could change the rear gear to a 3.89 I think this would help ! You need wheel speed at the hit so I would say less air pressure start at about 5.5 ! Put some weight in the front like 40 lbs ! You can allways take a little out later ! If you can get the car to go from a to b you can make small changes at a time ! One last thing how is the track it self ? And do you have some one to help you back up in the groove ? A lot of people think that they have to be in there tire tracks from there burn out but is more important to be in the groove on the track ! I hope this will help you !
Title: Re: calming the car down on the starting line
Post by: crider on October 23, 2018, 06:14:14 PM
Still fighting right turns. Would adjusting the wheelie bar slightly to the left possibly help? I've tried just about every other thing I can come up with, with air pressure and launch rpm and nothing seems to be helping.
Title: Re: calming the car down on the starting line
Post by: Curly1 on October 24, 2018, 09:46:51 AM
Thirty feet out it turns to the Right?  Are the front wheels in the air when it does it?
If they are not then I would think chassis is not square and or rear end not straight in car. It does not take much at all.

If they are in the air when it does it then that would tell me left rear tire is planting and hitting harder or wheelie bar steering it. Or as someone said one tire larger diameter than the other.
Title: Re: calming the car down on the starting line
Post by: racerken on October 24, 2018, 11:11:26 AM
Does it have a spool or open rear end.
Title: Re: calming the car down on the starting line
Post by: wideopen231 on October 24, 2018, 02:17:11 PM
I would measure rearend to motor plate both side and then check rear end is centered. If  all check out there I would swap tires around,maybe one has issue. If still goes right you know its not in tires,If goes left you have the problem
Title: Re: calming the car down on the starting line
Post by: crider on October 25, 2018, 03:18:20 AM
To answer some of the questions, I've lowered the wheelie bars enough now that the front tires are staying on the ground, and still pushing the front to the right. Also have measured tires diameter is less than 1/8" different side to side. I don't really think the rear would be out of line, because the car was running straight as an arrow until this issue just popped up out of nowhere, but I will sure check it. It's a spool rear diff. I had thought about swapping tires, maybe that's next. I'm running out of time to get any runs this fall
Title: Re: calming the car down on the starting line
Post by: dusterdave173 on October 25, 2018, 06:27:36 AM
Does it have a cracked frame support somewhere??
I remember Doug Herbert hauled across the USA got out trailer car nearly killed him--they stripped the tin off and due to wrong chassis support ( crew screw up ) it had cracked some supports
You seem to have tried everything--tires are within spec--WAS going straight
so??
That or you are not in the groove-- very Easy to do---rather---it is hard without experienced crew to get staged right in the groove in a dragster  makes all the diff in the world
Title: Re: calming the car down on the starting line
Post by: wideopen231 on October 25, 2018, 09:24:01 AM
Yea forgot about the its just started this. Then I would definitely check frame and then swap tires.If for no other reason than to remove ant doubt.
Title: Re: calming the car down on the starting line
Post by: masracingtd1167 on October 25, 2018, 10:11:22 AM
Both Chris and Dave are right about checking the frame and swapping the tires and I would do the same ! Did you add some weight to the front ? Did you drop your tire pressure It should give you some more wheel speed ! Those 10.5 tires are very aggressive and it is hard to get wheel speed with them ! How about taking some timing out like 28 degrees ! How close dose Chris wide open live to you ? See if he could come to the track with you ! I had a similar problem when I tried a different tire on mine and I just could not get the car to go straight went back to my 2585 Goodyears and the car was perfect !
Title: Re: calming the car down on the starting line
Post by: wideopen231 on October 25, 2018, 10:40:11 AM
If you are running Farmington I am about 45 minutes away. Just need cpl days notice and next two Saturdays are booked.Its muzzleloader and my family know not to die during those two weeks or Chris will not be there. Now if your doing midday so I can leave out around 3:30 and be in my stand come 5 o clock I am willing to help out.

Now Bill has me worried about my MT's on FED,bt then those who know me know getting wheels speed has never been my problem.Too much maybe.LOL
Title: Re: calming the car down on the starting line
Post by: JrFuel Hayden on October 25, 2018, 01:48:53 PM
Crider , I have benn following your posts, and I may not have THE answer, but here are a couple of my thoughts;
I assume your chassis and rear-end set-up is good since your car was going straight before, with no chassis changes, just more power ?
But again check the roll out of your slicks, and try swaping tires to see if it still turns right at about 30' .
If it was my JF car I would add at least 40 lbs to the nose if you are getting a quick yank of the front wheels at the hit, that might be adding to your problem if you have a short or stiff wheelie par.
My WB is a 5 foot 3 bar CM with no connectors between the bars, so I get some flex in the WB , a stiff WB will only make your problem worse when the WB hits.
Again , if it was my car and I added pressure to the right tire and it still goes more right, I would think it means the right tire is spinning more so the left slick steers the car to the right.
I notice you and a few other racers are using the M/T 33x10.5x15 tires, and just so know all the 10.5 tires were built for the 10.5 door car classes, where the cars weight 2-3k+ and shift allot more times than your PG , which means the sidewalls are stiffer, and softer compounds for better traction. Where as FED 2 speed cars want/need enough tire spin the keep the engine at it's HP RPM range.
I have tried the MT 33x10.5 a few times on our 1450lb [ with driver] Heritage all iron JrFuel car, mostly because a buddy of mine could not get them to work on his Heritage A/F car, mostly because he was looking for more tire growth , because it was a a stiffer side tire he did not get what he wanted. With our JF car we did get a bit better 60' times, but the GY 31x12x15 gave us better ET's, AND it drifted to the right, probly not the reason you are going right.     
What I would do if it was my car is keep adding front weight until the front wheels don't come up, raise the WB up to 2-2.5 "  check roll-out, check for chassis cracked or broke tubing [ we have cracked tubing from tire shake] try different launch RPM, or leave off the foot brake and tire pressures [ MT suggests 7-7 .25, but i see some guys are running 5-5.25, but check to see how fast they are running]. One thing that helped our 7.0's 186-189mph car is changing to a 1.69 first gear so it will not hit the tires so hard, and I run a looser converter [ 8500 rpm] that also helps not hit the tires so hard.
About converters, your car will improve when you get the converter to cloer match you engines power range. example your converter is stallin/ flashing at 6.2k but if you engine "come-on" at 7k she wil struggle for 1000 rpm. best way to get the right converter is to dyno your engine, if that's not possible ball park idea is it should stall about 1000-1500 below your shift RPM.
Another idea is to aim your GoPro camera at your tack to play back the goPro to see what the RPM drops to right after the shift [ which is your true stall rpm].
This is no dought too much info, so feel free to call me , 805-444-4489, cell
Jon     
Title: Re: calming the car down on the starting line
Post by: crider on October 25, 2018, 03:02:23 PM
Thanks Jon for all the info, seems like a few more Ideas to try. I have dropped the air down to 6psi. Haven't added a weigh bar yet, as lowering the wheelie bar got all the crazy launches under control, now it is just a slow push to the right instead of the I wonder which way it's gonna go this time action that I had going on.  I'll pull the tin back off and give everything a good check before the next time I go out. I had it all off when I was centering the wheelie bar, but didn't really check it closely. As for the converter, it was set up as a 6400 stall, and I'm shifting at 7200. But haven't been paying attention to the rpm drop to know the true stall speed. I really need to get this thing to run straight. I've had my hilborn setup back from Spud for a while now, but I want to have the car acting right before I open another can of tuning worms...lol I guess next time out I will switch the tires around. I don't think it is a lack of being in the groove, since it has done almost exactly the same thing 6 passes in a row and at 2 different tracks. after a quick slap of the throttle it goes as straight and smooth as you could ever ask for. I just need to fix the first 60 ft of the run.
Chris  if I haven't got this thing figured out by the end of hunting season I may have to take you up on the offer to help out. I could use a good pair of eyes on the outside of the car too
Title: Re: calming the car down on the starting line
Post by: wideopen231 on October 26, 2018, 03:19:35 AM
Let me know. 336 362 1785.Heck I love tuning a car more than driving anyway and little FED experience might payoff if my junk ever gets something to ride on to get it to track. Plus I have a go pro that will give recording thats better than old guys eyes,it rewinds.LOL
Title: Re: calming the car down on the starting line
Post by: masracingtd1167 on October 26, 2018, 08:12:58 AM
Sounds like you are going in the right direction and I also think that adding some weight to the front will get you down the track ! once you are going straight you can make small changes to see what it dose !I spent a lot of time on my car trying to keep as much weight to the front ! Things like your fuel tank battery fire bottle ! I even moved my ignition box and primer pump up front and I still have to add a little weight to mine ! If you can move some of your weight even if it is in the middle of the car to the front it will help ! Some of my Comp friends are running that 10.5 tire and having good luck with it but they are rear engine cars with big hp and a 3 speed trans ! i have never tried a 10.5 on my car but if I did it would be the 31 tall one !       
Title: Re: calming the car down on the starting line
Post by: dusterdave173 on October 26, 2018, 08:24:30 AM
I agree--I could not drive my car no way no how without the 44 lbs on the nose
FWIW we have decided 7 1/2 lbs in our MT 10.5x33 works best on our SBC car
Title: Re: calming the car down on the starting line
Post by: masracingtd1167 on October 26, 2018, 10:12:05 AM
I try to keep as much weight forward as possible
Title: Re: calming the car down on the starting line
Post by: masracingtd1167 on October 26, 2018, 11:13:09 AM
I was just looking back at some pictures of your car and I noticed that it has a torsion bar front end ! Is it possible that when the car leaves the axle has no load on it and it turns the front wheels a little to the right ? 
Title: Re: calming the car down on the starting line
Post by: crider on October 27, 2018, 05:08:58 AM
I have as much weight forward as I really can move up there. Fuel tank and trans cooler all the way up. Then battery and radiator right in front of the engine. Never thought about the possibility of front suspension travel turning the wheels. I don't think it is, but it's worth checking for sure. I really wish the monsoons would quit, seems like a month or more between dry days that I get to go to the track
Title: Re: calming the car down on the starting line
Post by: dusterdave173 on October 27, 2018, 09:01:17 AM
I have had good luck using my video camera--I  make sure it sees front end and my hands--I can replay a run and see if I was issue or car or track etc  Works great and --humbles you some--if not track surface it is usually me causing issue
It has helped me fine tune my driving
Just a thought
My car went through a spell where it went left--turns out if I hold wheel with a little preload to the right--and I mean a little--problem solved so......
Title: Re: calming the car down on the starting line
Post by: wideopen231 on October 27, 2018, 06:23:10 PM
Just a thought and only because its hit me before. Are you sure its because your hitting it too hard. I have backed cars off and caused me problem. I know Crider will know what this means as he has driven TA/FC.You can drive a spinning car but you can't drive a shaking car. Just a thought that came to me while reading tru some of your post.
Title: Re: calming the car down on the starting line
Post by: wideopen231 on October 27, 2018, 06:48:39 PM
Question. Have you made hit with timing where it was when going straight? If not that would be my top of list thing to do. GOLDEN rule when all else fails go back to baseline of good runs. If you backed it off you mave be making power up higher but pulled good amount off bottom end. Just throwing ideas at you.
Title: Re: calming the car down on the starting line
Post by: masracingtd1167 on November 18, 2018, 06:50:50 AM
I was just looking at an old picture of my car back in the 70's ! Look at how the front wheels would turn to the right when the car would launch !
Title: Re: calming the car down on the starting line
Post by: crider on November 18, 2018, 12:00:21 PM
That is a serious right turn there. Mine don't seem to be turning any, but then the car goes right with them on or off the ground. Hoping to go out one more time in a couple weeks and see if I can et it any better. It is at least to the point of being predictable, now I just need to keep it from pushing right. I picked up just over .2 with the timing change, I don't really want to go back with it...lol
Title: Re: calming the car down on the starting line
Post by: StigO on November 25, 2018, 12:42:20 PM
Have you tried to dump the timing out for a short period just after the hit? If I don't do that on my car it get crazy and big tireshake.
Also have notice that it usually the left tire that start shake on my car. So instead of adding pressure in right tire lower the pressure in left tire to make it spin easier.
Title: Re: calming the car down on the starting line
Post by: BK on November 26, 2018, 07:43:21 AM
That is a serious right turn there. Mine don't seem to be turning any, but then the car goes right with them on or off the ground. Hoping to go out one more time in a couple weeks and see if I can et it any better. It is at least to the point of being predictable, now I just need to keep it from pushing right. I picked up just over .2 with the timing change, I don't really want to go back with it...lol
Mine would drive right all the way through first gear then settle down after the shift. Figured it out when I noticed both front tires were feathered the same way. I should have figured it out with how much I was steering it left to 300 feet or so. Probably needed another 20 or so pounds up front.