Author Topic: Basic 355 combo  (Read 3609 times)

Offline opa1

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Basic 355 combo
« on: March 28, 2018, 02:42:52 PM »
I bought a 179wb Jr.Fuel roller. I want to set it up with a carb, gas and zoomies. I'm not really concerned how quick it is. I just want to have fun. It will also only run the 1/8 mile and is my first FED.

I would think the all up weight with driver is around 1500#. Not sure on this just a guess. The drivetrain specs are 4:86 gear, 31" tire, 1:76 glide.

I have a forged and balanced 355 flattop .005 deck short block. The cam I'm looking at is a Howards 112072-06. Specs out at 246/246 @ .050, 515/515 lift @ 1.5 ratio/ 549 @ 1.6 ratio, 106 on 102. 3200-6700 range. I have a std Victor Jr. 2975 and 750 carb.

For heads I have a choice of
 Performer RPM @ 2.02/1.6/170cc port/72cc chamber. DCR 7.52 static 9.22
World products S/R 1.94/1.5/ 170cc port/58cc chamber DCR 8.74 static 10.76
Engine Quest vortec style 1.94/1.5 170cc/64cc chamber DCR 8.26 static 10.15

I have the Performer RPM heads. The other heads were what I'm looking at. Does this combo look to be somewhere close? Any suggestions on which heads and compression to use?

Offline jeff/21

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Re: Basic 355 combo
« Reply #1 on: March 28, 2018, 04:52:49 PM »
we ran something similar   flat top vortec heads 58cc  o deck .030 head gasket carb on gas  4.86 gears and 10"x 30" tire  we could hot lap it very consistent good fed bracket car. when we started to add hp changed tires to 10x33 then it started to run hot and we changed to alky at first with a carb then injection.everything was normal again got rid of the water pump and rad we also tried 4.56 and 4.10 gears always ran better with 4.86
keep it simple and have fun

Offline opa1

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Re: Basic 355 combo
« Reply #2 on: March 28, 2018, 05:15:07 PM »
Thanks for your input. I'd like to go injection and alky, just not in the budget right now. I should have room for the horizontal radiator/fan.

What were your RPM's and speed in the 1/8 with the 4.86 10x30 tire?

Offline Frontenginedragsters

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Re: Basic 355 combo
« Reply #3 on: March 29, 2018, 08:06:01 AM »
OPA1:
 This is a copy of a posting I answered from just a few weeks ago:

Last year [2016 and 2017] we ran a 355 S.B.Chevy in a 175" WB Front engine dragster.
33" tall tires, 4.11 gear and Powerglide NO Trans Break. Leaving off idle.
Engine was very basic. 10 to 1 compression and un-ported 461 castings.
Enderle stacks on alcohol.
Camshaft was a Engle Flat Tappet Solid. 247*/252* on a 110* lobe separation.
Car ran 5.64 @ 122 MPH in the 1/8
It was assembled as a stepping stone from a Jr Dragster for our youngest son.
We had a ball racing it and won several local races.

If you use the cylinder heads that you own, your lower compression ratio will let you use cheaper gas.
Brings the cost of racing down and the fun up.

Matt Shaff
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« Last Edit: March 29, 2018, 08:16:55 AM by Frontenginedragsters »
Driving a Front Engine Dragster builds character and keeps you awake for a 1/4 mile at a time.
http://www.pro-formancespecialties.com/

Offline opa1

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Re: Basic 355 combo
« Reply #4 on: March 29, 2018, 08:33:17 AM »
OPA1:
 This is a copy of a posting I answered from just a few weeks ago:

Last year [2016 and 2017] we ran a 355 S.B.Chevy in a 175" WB Front engine dragster.
33" tall tires, 4.11 gear and Powerglide NO Trans Break. Leaving off idle.
Engine was very basic. 10 to 1 compression and un-ported 461 castings.
Enderle stacks on alcohol.
Camshaft was a Engle Flat Tappet Solid. 247*/252* on a 110* lobe separation.
Car ran 5.64 @ 122 MPH in the 1/8
It was assembled as a stepping stone from a Jr Dragster for our youngest son.
We had a ball racing it and won several local races.

If you use the cylinder heads that you own, your lower compression ratio will let you use cheaper gas.
Brings the cost of racing down and the fun up.

Matt Shaff
Pro-Formance Specialties
585-288-1499
That combo is very close to mine too. Any reason for running the 110 lsa other than a wider power curve? I've done some reading about using zoomies with gas/carb. I came up with mixed thoughts on it.
Using the performer rpm's will kick some of the dcr out but, it would be pump gas friendly. The aluminum would stay cooler too.

Offline Roger

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Re: Basic 355 combo
« Reply #5 on: March 29, 2018, 01:27:38 PM »
Looking at your combination of weight, gear,tire diameter, and an engine like yours making 400-425 hp, car should run the eighth mile in about 5.70 seconds at about 120 mph. Give or take. That's puts your finish line engine speed at about 6300-6400 rpm.
With that said, use your rpm heads, the savings in weight will offset any hp gain from increased compression from a smaller chamber. And you already have them.
Since your are using zoomies and aren't killing the engine with rpms, there might not be a big difference with cam timing. Since you will get no inertia scavenging or wave scavenging as collector headers would give you above maybe 5000rpm, I'd suggest giving the cam at least a 108*lsa and at lease 6 more degrees duration on the exhaust as compared to the intake. That will cause the exhaust valve to open earlier to aid in clearing the exhaust gas out and it will minimize the valve overlap to help defeat exhaust reversion into the intake manifold. Invest in a good torque convertor that stalls about 4000-4500 rpm and see what happens.
Most of all, get it running and enjoy!
« Last Edit: March 29, 2018, 01:37:32 PM by Roger »

Offline opa1

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Re: Basic 355 combo
« Reply #6 on: March 29, 2018, 01:44:31 PM »
Good info, Thanks. I'll look and see what cam profiles I can find. I'll post up my selections. 

Offline jeff/21

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Re: Basic 355 combo
« Reply #7 on: March 29, 2018, 04:57:18 PM »
it was a few years ago rpm was just under 7000 and speed was 125-6 the biggest was going from a big box Chinese torque to a name brand was good for .500 and easier to drive

Offline Frontenginedragsters

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Re: Basic 355 combo
« Reply #8 on: March 29, 2018, 06:55:08 PM »
I agree with Roger, 108* LSA if I was to do it again.
You will also get tired of gas real quick.
Alcohol is the way to fly.

Matt
Driving a Front Engine Dragster builds character and keeps you awake for a 1/4 mile at a time.
http://www.pro-formancespecialties.com/

Offline opa1

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Re: Basic 355 combo
« Reply #9 on: March 29, 2018, 09:04:22 PM »
Looking at @jeff/21 rpm #7000 and what @Roger calculated 6300/6400 is a big difference in cam choices. With the low compression I was looking at this to keep cylinder pressure up. I'm not sure it will rpm enough. The figures I calculated were closer to @roger rpm's.

Howards solid 110102-08,  http://www.competitionproducts.com/Howards-Cams-Mechanical-Flat-Tappet-Camshaft-Chevy-Small-Block-240_246-050-505_520-108/productinfo/110102-08/#.Wr25DExFw2w
240/246@.050, 505/520@1.5, 108/104 3000/6200


« Last Edit: March 29, 2018, 09:18:39 PM by opa1 »

Offline Roger

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Re: Basic 355 combo
« Reply #10 on: March 30, 2018, 08:25:10 AM »
I think that cam looks like a good pick. I'd suggest using no more than the required spring pressure with the flat tappet and break it in correctly. And I think you're right, you'll probably start running out of power just before the finish line because of the limited intake port area and compression. But that won't hurt a thing, by the time you feel it, you're on the brakes anyway:)

Offline opa1

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Re: Basic 355 combo
« Reply #11 on: March 30, 2018, 09:23:10 AM »
Thanks! I'm going to try and keep the valve train as lite as possible. I agree with the spring selection. I've run door cars most of my life. Building a engine for the FED is like stepping back a bit. :)

EDIT: What's the thought on Zoomies? 1  5/8 or 1 3/4. I'll be using the 6 bolt flange.
« Last Edit: March 30, 2018, 12:21:08 PM by opa1 »

Offline jeff/21

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Re: Basic 355 combo
« Reply #12 on: March 30, 2018, 04:54:46 PM »
we had the cam ground by Schneider talked to jerry and his advice was pretty close and i've used his cams since  it was a flat tappet used the lightest springs possible  the rpm was when running it through the speed trap   

Offline jeff/21

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Re: Basic 355 combo
« Reply #13 on: March 30, 2018, 05:03:37 PM »
Building a engine for the FED is like stepping back a bit
why would you say that, other than cam a torque converter selection every thing else is the same

Offline wideopen231

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Re: Basic 355 combo
« Reply #14 on: March 30, 2018, 06:29:51 PM »
Think he meant keeping it mild is step back. 

Please nobody take this as anything other than statement. I'm always amazed at you guys who can build milder setup and just run for fun. I might start out for mild but then the just little more thing happens. Little more compression,few degrees more cam,little better head,litle hotter ignition and litle more money I can get this much more power.Before I am out the gate at $3000 build is up to 10k and a 500 hp motor is buzzing close to 1000 hp. Heck I am the guy with 100 hp Harley Evo motor in corner for my wheel chair when I old.
Relecting obama is like shooting right foot because it did not hurt enough when you shot left foot