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Old 01-15-2009, 12:35 AM   #1
Camper Power
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Question increase torque

my engine has no balls when it comes to lower rpms. whats a good way to increase engine torque without spending much money.
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Old 01-15-2009, 12:38 AM   #2
vasquezmrysvll
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Re: increase torque

what type of manifold are you running? single plane will kill low end performance. also what head/cam combo?
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Old 01-15-2009, 12:40 AM   #3
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Re: increase torque

Manifolds > Headers at low end torque.

A stock intake will often times yeild better low end torque then aftermarket ones aimed at more upper end HP.
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Old 01-15-2009, 12:58 AM   #4
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Re: increase torque

For your headers, best bet is shorty headers with small tubes [1 1/2"] and exhaust pipes no bigger than 2 1/4"....2" is better for low end torque.

A daul plane manifold that gets best performance at 1500 rpm and up will do fine. Edelbrock's Performer EPS does this. If you really want to move when towing or hauling, get a mild cam that comes in around 1000 rpm. I have this setup on a mostly stock 350....moves nicely off idle for a 4300lb truck with 400 lbs in it daily [me and a few tools].
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Old 01-15-2009, 09:18 AM   #5
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Re: increase torque

What motor is in your truck?
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Old 01-15-2009, 09:23 AM   #6
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Re: increase torque

Quote:
Originally Posted by djracer View Post
What motor is in your truck?
In his sig:
Quote:
1970 Chevy Custom Camper Special, daily driver, 350 with edelbrock intake manifold and carb, cammed, headers, flowmaster glasspacks, HEI, turbo 350 (aka: The Purple People Eater)
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Old 01-15-2009, 12:47 PM   #7
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Re: increase torque

What rear axle do you have?
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Old 01-15-2009, 01:44 PM   #8
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Re: increase torque

For what you got I would have to say your cam is the problem. It must be a top end cam. I'd put the lowest or next highest (from the lowest) RPM range perf. cam they make.
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Old 01-15-2009, 02:12 PM   #9
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Re: increase torque

I would say the cam is the problem also.
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My Pass Time Show http://s129.photobucket.com/albums/p...Chapter1-0.mp4

So Far my best Times are:

Motor only:
6.44 1/8 @ 104.13
10.39 1/4 @ 125.83

Nitrous Times:
5.785 1/8 @ 118.65 with a 1.336 60ft
9.168 1/4 @ 142.58 with a 250 shot dead out of the hole!
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Old 01-15-2009, 06:21 PM   #10
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Re: increase torque

I agree with the cam.The biggest performance mistake most people make is to overcam overcarb an engine.Rather than matching components for the overall type of performance they go for the "Bigger is better" plan that doesn't work for anyone but goverment.
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Old 01-15-2009, 06:57 PM   #11
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Re: increase torque

I would look at two items :

rear end gears and what cam do you have...

I agree that sometimes you can over cam a motor killing it's low end torque and power.
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Old 01-15-2009, 08:46 PM   #12
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Re: increase torque

What camshaft, what intake, and what carb are you running? what are your rear gears? I agree with the posts above that state you may be overcammed. Bigger is not better for a street driven heavy vehicle with a small v8. Big cams sacrifice low end torque for mid-upper RPM power.

Another thought: Maybe the HEI is not timed as well as it could be? Consider your initial advance as well as mechanical advance. Perhaps swapping to lighter springs in the HEI would help to bring total timing in earlier. Also check out your vacuum advance... is it even working? look for vacuum leaks on the engine... that will definitely hurt performance! Maybe the carb is not jetted as well as it could be? Maybe the secondaries are not opening soon enough?
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Old 01-15-2009, 09:55 PM   #13
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Re: increase torque

i couldnt really tell you what exactly what the engine has cause the po did all the mods to it before i bought it. it has 4.11 gears, the timing is set to 10 tdc at idle, cant remember what the total advance is, im planning on switching to manifold vacume soon but i dont know what it does to engine performance. over the weekend il probably pull the valve covers to get the head numbers. i was thinking of gettin a gm aluminum intake cause a good friend of mine said they are one of the best manifolds out there, hes runnin them on his 67 c10, his 80 vette, and i think his dad has them on his 72 cheyenne. heres some pics to see what i know i have.
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Old 01-15-2009, 11:00 PM   #14
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Re: increase torque

Cadillac 500. GM 502. GM 454.

Just kidding. All the above info is right on the money.
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Old 01-15-2009, 11:56 PM   #15
djracer
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Re: increase torque

gm sells a cam they call a 300hp 350 cam and they work well without killing all your torque.
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Special Thanks to All who have helped on the TRUCK!

My Pass Time Show http://s129.photobucket.com/albums/p...Chapter1-0.mp4

So Far my best Times are:

Motor only:
6.44 1/8 @ 104.13
10.39 1/4 @ 125.83

Nitrous Times:
5.785 1/8 @ 118.65 with a 1.336 60ft
9.168 1/4 @ 142.58 with a 250 shot dead out of the hole!
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Old 01-16-2009, 07:11 PM   #16
JAKES 68GMC
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Re: increase torque

My 350 in my GMC has a Crane "truck-power" cam, headers with 2'' duals, edelbrock intake and a holley 600 4bbl, and for a big old truck, she friggin flys!!! I'm thinking about a different set of heads though, I think mine now are holding my engine back alot, powerwise.

PS...cam specs are .427/.454 lift...look up Crane truck power cams in either a jegs or summit catalog, it'll be right there.

Last edited by JAKES 68GMC; 01-16-2009 at 07:15 PM.
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