Messages

61

Your Builds / Photo Gallery / Re: Ed Mabry 71 Jr. Fuel

« on: July 23, 2018, 05:26:27 AM »

It should not be an issue with your application but as a matter of principle please lose the clear plastic burn down hoses. In any sort of fire situation those things will be gone in an instant. A few years back I re bodied the Boss Bird Pontiac nostalgia funny car after a fire.  They had a fitting break on the fuel pump to start the incident and the fire was bad enough but it got lots worse when the clear hose connecting the puke tank to the shoulder hoop bosses went away and let the fire get to the nitro diluted oil in the tank.

Roo

62

Roo Man's Room / Re: Steering arms

« on: July 23, 2018, 05:18:51 AM »

If you are connecting the drag link to the left spindle the length of the arms that connect to spindles to each other has absolutely no effect on the steering ratio but using a bell crank does make a difference. I have not built a car with a bell crank for a long time for a couple of reasons.
 First, although the wheels are generally pointed straight ahead on the track (or should be) and thus ackerman geometry is not an issue things get different when moving the car around the pits or the shop. A single tie rod is pretty simple while the fact that the bell crank swings in an arc makes the placement of the inner tie rod ends a little more complicated. Using a bell crank to steer to one wheel and then running a regular tie rod is a better idea and pretty much mandatory with front suspension.
 Second, there are just more parts in a bell crank set up. An extra pair of rod ends, the bell crank itself (including the pivot and its mount).
 At one time long ago when 30 plus degrees of caster was the norm the bell crank package helped as it makes it easier to rotate the spindle on the king pin compared with trying to push the spindle down on the end of the axle due to the big caster number. Don Long cars all steered with the drag link to the spindle and all big show funny cars are that way as well now (and they used to run bell cranks) and if it is good enough for them it works for me.

Roo

63

Front Engine Dragsters / Re: Most comfortable Under wear??

« on: July 23, 2018, 04:53:51 AM »

I used the Carbon X , including the head sock, in the fuel car (with a -20 suit)  and even in near 100 degree heat I never had a problem with sweat as it appears to be very good at wicking the moisture away.

Roo

64

Front Engine Dragsters / Re: Chute lever installation in FED

« on: July 23, 2018, 04:49:08 AM »

I disagree with Gino's cable recommendation. A small single wire cable is all you need (like a choke cable if you are old enough to know what that is). The Morse style cables are stiff and bulky and require larger hardware at the mounting point. I usually mount the lever/s just ahead of the front cage hoop in a push configuration. That way if things ever get really ugly on a run you can slap the back of your hand against the hoop, slide it down and the lever is right there. As Greg notes the bare cable deal also works provided that you have the cable routed so that the lever will pull it far enough to open the chute pack--the jacketed installation controls that a little better.

Roo

65

Front Engine Dragsters / Re: calming the car down on the starting line

« 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

66

Roo Man's Room / Re: Basic question

« on: June 20, 2018, 10:22:54 AM »

Most of my later cars have tabs on the lower frame rails at the rear so that the car can be pinned to a stand (or Pro Jacks if you are bucks up)

Roo

67

Roo Man's Room / Re: Cutting and butt weld upper frame rail

« on: June 18, 2018, 05:36:43 AM »

Paul, sorry that I was not around to reply last week but we were busy getting ready for and going to Bowling Green. As noted already the splice deal is perfectly acceptable if done correctly. I did a shoulder hoop replacement on Paul "Nobody" Schultz's NT/F car when it was owned by Brad Green and joined it between the steering cross member and the rear end uprights. It has been raced quite a bit since then and passed tech last weekend at Bowling Green where Joe Lease was looking pretty closely at the fuel cars.

Roo

68

Front Engine Dragsters / Re: Sixties front engine dragster owner/builder

« on: June 18, 2018, 05:24:30 AM »

The main reason for the greater caster in a front engine dragster is the fact that the front wheels carry a lot less weight than an altered or gasser. The same goes for rear engine diggers and 20 degrees is pretty much the standard there as well. The big show funny cars also ran more due to their speed but once the front downforce got higher (aero improvements, dragging the front lip etc) they backed off. When I was at JFR they were only running 6 degrees.

Roo

69

Front Engine Dragsters / Re: Driving suit

« on: June 11, 2018, 01:08:39 PM »

I spent around 40 minutes strapped into the NT/F car at Bowling Green in 2010 with the temperature and humidity numbers both at almost 100. What saved me was the Carbon-X underwear and head sock. It tends to wick the moisture away from your skin and I was never that uncomfortable.

Roo

70

Front Engine Dragsters / Re: Sixties front engine dragster owner/builder

« on: June 11, 2018, 03:56:31 AM »

Based on the photos it looks like the front end had waaaay more caster than is needed / desired. I'd look at taking most of it out. Keep seven degrees for a start.

Seven degrees may be OK for an altered (I like about 12-14) but 20 is right around the mark for a front engine dragster. The extreme caster run by most of the early diggers (30 degrees plus) is actually only a problem while backing up (and Brendan Murry still runs 30 in his NT/F).

Roo

71

Roo Man's Room / Re: Steering shaft

« on: June 07, 2018, 02:25:27 PM »

At anything over about 160" wheelbase I would normally use at least a 2 piece drag link. I usually run the front section at around four feet (or approximately as long as the radius rods if the car has a sprung front end).

Roo

72

Roo Man's Room / Re: types of chassis (back half)

« on: June 05, 2018, 04:29:38 AM »

I am a first time builder at least for a dragster. I've built many street rod frames and a Bonneville Lakester using dom tubing. But that tubing was quite a bit thicker .125 thick, and a lot of it. That lakester car is 23 feet long and weighs 2,300 pounds. Currently I drive a door slammer in 1/8 mile bracket racing but need more excitement. I'm quitting Bonneville after this year and will try putting it's engine in a fed this winter. The motor is a Chev LS3 all aluminum engine. I haven't seen any LS engines in fed's, is that because you can't nostalgia race?

That may be part of it but I think that the main reason is that most of the racers involved in the nostalgia scene are simply old school and prefer racing against similar cars. There is no rule that says that you can't run an LS and there are plenty of manufacturers making parts to run them with distributors and carburettors so that they look "correct". It does not take much in the way of an LS to go fast. The motorsports program at IUPUI (a joint Indiana/Purdue University college here in Indy) has a Spitzer S/C dragster with a GM supplied LS7 Corvette motor. It is stock apart from a nice set of headers and a conversion to cable throttle (from drive by wire) and with the throttle stop disconnected it runs mid 8's.

Roo

73

Roo Man's Room / Re: Helmet bar padding

« on: June 04, 2018, 04:22:33 AM »

This link may work a little better: http://www.garvinmotorsports.com/
 Jeff Garvin is a former fuel car crew guy so he has "been there and done that" at the top level of drag racing.

Roo

74

Roo Man's Room / Re: types of chassis (back half)

« on: June 04, 2018, 04:17:35 AM »

All Don Long and most Frank Huzar (RCS) and Roy Fjasted (SPE) cars had the upper and lower loops while Woody Gilmore favored having the lower rails roll up to the shoulder hoop. Back in the day the former may have been a little lighter but with current rules regarding the positioning of tubing to shield the seat from impact both versions weigh about the same. I like the Woody style and build my cars that way even though it involves a bit more work in the area of compound bends and notch alignment. For a first time builder the double loop version is probably simpler.

Roo

75

Roo Man's Room / Re: Building new chassis

« on: April 25, 2018, 04:46:21 AM »

As with anything SFI, the specs are the minimum required so additional tubing (or diameter/wall thickness) is allowed. That said, "some's good, more is better" is not necessarily a good thing if you get TOO carried away with bigger diameters and heavier wall tubing as all that adds is weight and stiffness.

Roo