Need More Power!
Thread Starter
Safety Car
Joined: Apr 2000
Posts: 3,802
Likes: 61
From: Wichita KS
Need More Power!
Ok, I think my ride needs a performance boost. The combination of M20, 3.08 rear and LS5 seems pretty weak. I'm pretty sure I can't even spin the tires without a massive rpm clutch dump.
I don't want a dragster but I want some more muscle from it. I saw a cam and lifter for a 454. I think it was a Competition Cam 270.
Any suggestions? Yes the engine is original so I don't want to do anything like decking and risk loosing my number pad.
cc
I don't want a dragster but I want some more muscle from it. I saw a cam and lifter for a 454. I think it was a Competition Cam 270.
Any suggestions? Yes the engine is original so I don't want to do anything like decking and risk loosing my number pad.
cc
Safety Car
Joined: Oct 2005
Posts: 3,570
Likes: 1
From: Algonac Michigan
Gotta get that puppy to breathe. First get the carb tuned by someone you can trust. I don't know as much about big blocks but like any other motor you may want to install a new exhaust. Then(hold on tight to your wallet at this point)exhaust cam and heads.
Just my .02
Just my .02
Thread Starter
Safety Car
Joined: Apr 2000
Posts: 3,802
Likes: 61
From: Wichita KS
The thing about it is that I watch the tach and it seems this engine spends most of its time in the 2000-3500 rpm range. It takes forever
to get into the higher rpms even in first gear.
It has to be because of the tall rear gears and wide ratio shifter.
This car is supposed to have 455 lb-ft of torque but there is no way to use it with this setup.
cc
to get into the higher rpms even in first gear.
It has to be because of the tall rear gears and wide ratio shifter.
This car is supposed to have 455 lb-ft of torque but there is no way to use it with this setup.
cc
Thread Starter
Safety Car
Joined: Apr 2000
Posts: 3,802
Likes: 61
From: Wichita KS
Timing is right on spec. Carb is a reman unit from Advance Auto so I'm sure it's not set up for the best performance.
Factory carb is extremely scarce and runs around $900 in rebuildable condition.
cc
Factory carb is extremely scarce and runs around $900 in rebuildable condition.
cc
Le Mans Master
Joined: Jul 2005
Posts: 5,752
Likes: 4
From: Austin Texas
Usually a sluggish engine has insufficient timing advance, or the secondaries are not opening fully or at all. I had a big-block, 3.08 gears and a close ratio M-21....it would destroy the tires from a clutch dump.
Thread Starter
Safety Car
Joined: Apr 2000
Posts: 3,802
Likes: 61
From: Wichita KS
I'll check out the carb. I think the secondaries are mechanical but they may need adjustment because I don't think I've ever seen them open fully when I operate the linkage by hand.
cc
cc
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Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
First off if you want anything to even begin to happen you will need to change that gear to a minimum of a 3.73. And truthfully a 4.11 is even better. Otherwise your waisting your time and money with relativily stock parts. Screwing around with the carb and distributor may make it worse.
Le Mans Master
Joined: Jul 2005
Posts: 5,752
Likes: 4
From: Austin Texas
Racer
Joined: Mar 2005
Posts: 393
Likes: 3
From: Dallas, TX
i agree with ironcross, get some different gears and see how you like that, then start with the other stuff to turn your mild ride into a tire fryer, that being heads, cam, intake, exhaust, and maybe even a demon carb or whatever your preference is. whatever you decide on good luck and just remember its only money and you cant take it with you.
-alex
-alex
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
I think you have a more basic problem than gear set or head flow. You shouldn't have the problem you're describing with your set-up. I vote for the carb being the problem. There are so many things on the carb that can kill performance. As mentioned, have someone else push the accel pedal to the floor while you check to see if the throttle plates do go to WOT position. Check the carb and linkage out first....THEN go for the hi-performance stuff [if you still need it]. Good luck.
Safety Car
Joined: Oct 2005
Posts: 3,570
Likes: 1
From: Algonac Michigan
What carb did it come with from the factory and why is it so expensive???
Thread Starter
Safety Car
Joined: Apr 2000
Posts: 3,802
Likes: 61
From: Wichita KS
Safety Car
Joined: Oct 2005
Posts: 3,570
Likes: 1
From: Algonac Michigan
I had a Holly on my car when I bought it and I replaced it with a 77 q-jet(on Lars recomendation) and it runs great. After a rebuild of course. The thing you have to make sure of is that you do get a unmolested carb. I think I paid 75 or $100.00 on ebay. Along with a good rebuild and proper jets you will be fine.
Maybe you'll get luckey and lars will chime in later
If not e-mail him at V8FastCars@msn.com
Maybe you'll get luckey and lars will chime in later
If not e-mail him at V8FastCars@msn.com
Burning Brakes
Joined: Apr 2004
Posts: 847
Likes: 0
From: Des Allemands LA
I woulod definetly do the tuning thing before changing gears. 3.08's are not a bad all around gear to have, especially with a BigBlock. Get the timing and carb straight before the gears and I think you will be happy.
Racer
Joined: Apr 2005
Posts: 465
Likes: 1
From: FRANCE (Lyon)
BB with M20 and 3.08 works great but great is very subjective!
had a 1/4miles time or a dyno for a good tunning (with a good carb brad new is better than a cheap rebuild one)
and after if you find it's enough, go to change gear and cams, .......
Hopes this help!
had a 1/4miles time or a dyno for a good tunning (with a good carb brad new is better than a cheap rebuild one)
and after if you find it's enough, go to change gear and cams, .......
Hopes this help!