# How to kill low end torque?



## Mr Peabody (Jun 23, 2014)

My race car will carry the front wheels all the way thru first get and I'm running 1.5's 60 foot times. But I'm only running low twelve's at a best mph of 104. The engine is a mostly stock 455 with high compression, a crane cam with 230 intake and 240 exhaust at .050. Stock ram air intake with a quadrajet carb. Car weighs 3900 lbs with 456 gears and a th350 with 2.75 first gear. I need to kill the bottom end and get some more top end power, what would be the easiest way to do this. Rear end and trans are not an option to change, too much labor involved. Any suggestions?


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## GotTogO (Jul 25, 2013)

Nitrous kit.


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## ALKYGTO (Mar 29, 2010)

Lighten your car up. Why so much gear? Gear is a torque multiplier. What rpm are you going through the traps at?


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## Mr Peabody (Jun 23, 2014)

ALKYGTO said:


> Lighten your car up. Why so much gear? Gear is a torque multiplier. What rpm are you going through the traps at?


Gear was in the car when I bought it, I can't find a way of taking any more weight out, I am probably under 3700 lbs by now, haven't been on a scale yet. Going thru the traps at around 6000.


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## ALKYGTO (Mar 29, 2010)

6000 RPM through the traps. Okay, what is the max RPM of the engine? I'm just guessing but I'm going to say at 6000 with a 455 you are done. Now to maximize your "performance" ideally you should be at max rpm when going through the traps so either you are using the max efficiency of he engine or you are holding it back with too much gear. Greater speed at the end of the track is going to mean more RPM or you need a higher gear ratio to hit your projected speed.

Use this calculator from Wallace Racing and see what you come up with. No time this morning as I'm in to work early.

ET-MPH-HP Calculator :lurk:


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## geeteeohguy (Feb 2, 2008)

What Alky said. I'd bet you'd do much better with a 3.73 gear or even a 3.55.


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## BearGFR (Aug 25, 2008)

If you can't change the rear gear or the trans, then try some taller rear tires. You don't want to kill torque, especially with 60 ft times like you're getting. 1/100 th at the line is worth 1/10 th through the traps. You just need some longer legs. Taller tires take you in the same direction that less rear gear would.

Bear


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## 05GTO (Oct 6, 2004)

BearGFR said:


> If you can't change the rear gear or the trans, then try some taller rear tires. You don't want to kill torque, especially with 60 ft times like you're getting. 1/100 th at the line is worth 1/10 th through the traps. You just need some longer legs. Taller tires take you in the same direction that less rear gear would.
> 
> Bear


:agree

Another option would be to change the ring and pinion to a 3.90 and keep the 4.56 for the 1/8 track,

High performance Yukon Ring & Pinion gear set for GM 8.2" (Buick, Oldsmobile, and Pontiac) in 3.90 - YG GMBOP-390


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## chuckha62 (Apr 5, 2010)

I'll tell ya what killed my low end torque... An Edelbrock Torker intake manifold!


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## PontiacJim (Dec 29, 2012)

Retard the cam timing a few degrees to takes some low end torque out and add more upper HP. You want to be sure you have enough valve to piston clearance as you did not state cam lift.


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## geeteeohguy (Feb 2, 2008)

Also, retarding the ignition timing (distributor) will do the same thing to some degree.


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## Mr Peabody (Jun 23, 2014)

The local track will be closed until Sept., so I haven't had a chance to try any changes yet. I am going to retard cam timing and try a little larger carb, I believe I'm running out of air in the higher rpm ranges. I also have a new 428 engine in the shop that will be finished this fall, it should have a higher rpm potential.


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## ALKYGTO (Mar 29, 2010)

Do you have access to a local chassis dyno? They can be a great tool for tuning and you could try out a different carb, change timing etc. Best advise I can give you on dyno time is be prepared as if you were going to the track.


Love that wagon too.....can you post up some pictures of it? Try the garage feature on here.


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## 1972LeMans (May 4, 2014)

A little off topic but what are you putting to the wheels? 

Sent from AutoGuide.com App


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