Drag racing Question

425/409ER

425/409ER

Well Known Member
Since a lot of you guys are of my age group I have a drag race question, that is, I race an 80 Camaro with a Peanut Port 7.9 comp 461 BB Chevy engine. It runs 11.90's in the heat with 4.10 gears and a 4K converter. Now some race guys are saying that the car would ET better with 3.31 or a 3.08 gear and a 5K converter but I really think going down to that high of a gear would slow the car down. I am able to pull the engine to 6K very easy. What say you racers, I look forward to your opinions.
 
Fathead Racing

Fathead Racing

Well Known Member
Supporting Member 7
How tall is the tire your running? A cheap experiment would be a taller tire to see if it picks up any. If you can fit it under the car. That's the same thing as running a lower numerical gear.
 
D

Don Jacks

Well Seasoned Member
Supporting Member 3
What are your 60 ft.times under those conditions?What do you have in the way of traction enhancements[traction bars,tubbed,ect.]? What size tire and what type are you running?
 
425/409ER

425/409ER

Well Known Member
Let's see here, The car has run 1.57 60ft. in the 1/4 mile, tires are 28X9", SSM lift bars that work very well. Now last year the car would hit 6K at around a 1000ft. but that was before I rebuilt the turbo 400. This year I went to the local 1/8 mile track 60ft's dropped but that was due to the poor track cond. (not hooking off the line) but the good result was my 1/8mi. MPH went up from last year, 89.5 to 92.7 so the car is either making more power or the rebuilt trans is locking up better. I have tried a taller tire in the past but it was with a SB Chevy 350 and the car slowed down. I also went to a 4.88 gear with that 350 and the car ran the same times except the 60ft. was a little better everything else was the same. Drag racing is funny, things that you don't expect to work, do, things that are supposed to work, don't.
 
R

RussC

Well Known Member
So at this point we don't know what the rpms are at the stripe. But it sounds like the trans was slipping before the rebuild...so maybe you are at 6k at 1200 ft?? I don't know where your motor works... but that sounds ok to me.
My personal opinion is that if you went to a 3.31 the car would be quicker....if you were going to California. The 4.10 will get you to the finish line quicker. I might want to try a 4.56. I just don't know what the motor is capable of.

Remember...advice from race track groupies...and maybe website gurus is generally worth what you pay for it. You know your car the very best...and your judgement is probably the best. Good luck....Russ
 
425/409ER

425/409ER

Well Known Member
La Hot Rods said:
Did your 1/8 get better mph because you spun leaving the line?
How many laps do you have on this combination?
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I don't think it spun very hard just a couple of chirps that I could hear. The car did pull harder from the 330 ft on than last year. The engine only has around 25 passes on it. The last 3 engines have been the same way, all would hit around 6000 to 6200 by a 1000 ft. that's the reason I went through the trans as one of my transmission builders says he hates the alto reds and kolene steel combos. He says after time they slip too much in high gear. This time I used the alto greens and plain steels.
 
La Hot Rods

La Hot Rods

Well Seasoned Member
Supporting Member 15
What is your RPM range of your cam?
If you have the small port big block heads I would think it would not want a bunch of RPM.
 
425/409ER

425/409ER

Well Known Member
La Hot Rods said:
What is your RPM range of your cam?
If you have the small port big block heads I would think it would not want a bunch of RPM.
Click to expand...



The 461 has 236 Peanut Port heads on it, the little tiny ones, it pulls to 6K very easy and the RPM's and the power drops off after that. I was amazed that these little ports could RPM that much.
 
425/409ER

425/409ER

Well Known Member
Don Jacks said:
Try going with a 27 or 28 inch tall tire.I used a 28x10 with good results in the past.
Click to expand...

I have 28X9 now and have used the 10" tire but I get a better contact patch with the 9". I could try to put a 30" radial slick on the car as that would drop the gear down to a around a 3.73, this might work with the BB Chevy better than when I tried it with a SB. Car slowed down on that occasion.
 
Ishiftem

Ishiftem

Well Known Member
Supporting Member 2
I agree with James. It might rpm to 6k, but I highly doubt it makes power there and would be quicker shifting earlier. I would try a 3.73 or taller tire. Leave the converter alone.
 
425/409ER

425/409ER

Well Known Member
Barry Taylor said:
Ditch the peanut heads and re-cam it. Leave everything else alone JMO! BT
Click to expand...

I could sure do that, I have 781's and 990's, But do you honestly think that those heads are going to make a bunch more power that the 236 PP heads? I think not, let me tell you my reasons why. When I started on this I read about a guy who sells PP heads engines and he calls himself Vortecpro. His name is Mark and this guy is real smart when it comes to racing with the little port BB heads. His Chevelle combo that has is a 461 PP motor which had more porting and compression than I have, it runs 10.60's@128 in Denver air, that's pretty good in my book. This combo of his has almost made 600hp and it's with a summit hyd. flat tappet cam and a dual plane intake. I do know what my 781's flow but this combo with the little ports has surprised me much more than any close chambered big port heads I have ever used. No matter what head I use on this flat top piston engine with open chambered heads, it will make only little gains. Matter of fact the 990's that GM put's on their HO 454 only make 425hp and I think this combo is making that or a little more right now.
 
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