Power issues
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Heel & Toe
Joined: Mar 2021
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Power issues
I am currently having issues with power in the low range but once i hit 3rd gear it takes off like a bandit. Could this be caused by my intake manifold? It currently has an edelbrock torker ii 2-0 with edelbrock 1407 carb. Oh i have 74 454.
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Apr 15, 2021, 08:00 AM
Dr. Detroit
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From: New Braunfels Texas
Race Director
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A Torquer II power range doesn’t start until 2500 rpm and comes on strong at 3000. Almost sounds normal to me.
Burning Brakes
Joined: Nov 2012
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From: Indianapolis IN
Do you mean that in first and second gears it doesn't pull as hard as it does in third gear ?
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Heel & Toe
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Burning Brakes
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I doubt if it's the torker as I had one on my 427 and they're good to about 6000rpm.I would look for a vacuum leak which has more issues a low speeds then after you're up to speed or timing not set right or not advancing fast enough.
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Heel & Toe
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Thread Starter
Heel & Toe
Joined: Mar 2021
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So I have been reading a bunch of stuff and it could possibly be my carb is not tuned correctly. I was also thinking about the intake manifold because it is rated for higher rpms. I'm going to start with the carb and see where that leads. Thanks so much for the help!!! I definitely have a lot more to learn but I'm gaining
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Is my vette stock?? HAHA
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It doesnt sound like its all your engine, it sounds like your gearing too. You are using the same rpm range in every gear. you run your motor up to say 2500rpm to 3000rpm , then shift, run it up again , then shift. Why is that rpm different than your rpm on the highway? It could be that your gearing s so high for better mileage or to keep the rpm at highway speed down that it is making your city driving suffer.
To tell if its your carburetor giving you the bog, you need to get up to say 50mph in fourth, shift down to 3rd and floor it. If it bog then its the air flap openning to fast and giving you a lean bog. That is what the old quadrabog was and edelbrock has the same style air flap on the secondaries. On a quadrajet the airflap has an adjustable spring and the new edelbrock AVS carbs have and adjustable spring on that door. the regular and older edelbrocks do not.
That same symptom could also be your accelerator pump is not working or on the weakest setting.
To tell if its your carburetor giving you the bog, you need to get up to say 50mph in fourth, shift down to 3rd and floor it. If it bog then its the air flap openning to fast and giving you a lean bog. That is what the old quadrabog was and edelbrock has the same style air flap on the secondaries. On a quadrajet the airflap has an adjustable spring and the new edelbrock AVS carbs have and adjustable spring on that door. the regular and older edelbrocks do not.
That same symptom could also be your accelerator pump is not working or on the weakest setting.
Last edited by Rescue Rogers; Apr 15, 2021 at 07:17 AM.
Dr. Detroit
Joined: Mar 2012
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From: New Braunfels Texas
On a stock-ish 454 that manifold has nothing to do with it.......the ports are very small and promote velocity, plus you probably have 17+ inches of vacuum.....that is more than enough to effectively signal the carb from a dead stop.
Your issue is in the tuning......most likely the advance curve is very soft as you do not have power til way upstairs......
Pay little mind to manufacturer descriptions of 30 year old products like the Torker 2O......that intake is a compromise piece designed for nothing but hood clearance......you wouldn't run it on a serious piece as it would be down a ton of power, so saying it has a "power range" is kind of an oxymoron......
One thing I have found is that the damn thing works rather well up to about 450 horsepower.......after that it is a bottleneck.
Jebby
Your issue is in the tuning......most likely the advance curve is very soft as you do not have power til way upstairs......
Pay little mind to manufacturer descriptions of 30 year old products like the Torker 2O......that intake is a compromise piece designed for nothing but hood clearance......you wouldn't run it on a serious piece as it would be down a ton of power, so saying it has a "power range" is kind of an oxymoron......
One thing I have found is that the damn thing works rather well up to about 450 horsepower.......after that it is a bottleneck.
Jebby
Is my vette stock?? HAHA
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Jebby makes a good pint, did you just do a tune up recently?
Dr. Detroit
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From: New Braunfels Texas
If it bog then its the air flap openning to fast and giving you a lean bog. That is what the old quadrabog was and edelbrock has the same style air flap on the secondaries. On a quadrajet the airflap has an adjustable spring and the new edelbrock AVS carbs have and adjustable spring on that door
That same symptom could also be your accelerator pump is not working or on the weakest setting.
That same symptom could also be your accelerator pump is not working or on the weakest setting.
Jebby
Is my vette stock?? HAHA
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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When I get my car running I think I will....I've got to get away for a while, my spelling is suffering
Old Pro Solo Guy
Joined: Dec 2017
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From: Marlton NJ
Jebbys power valve flap comment is spot on.
Also do not forget to tune the timing curve to GM performance recommendations if you have not already done so. That wakes up the lower rpm ranges in particular.
With a 454 4 spd you should have no bog and that car should scoot.! With any kind of rear gear. Get the distrib tuned "right"
Also do not forget to tune the timing curve to GM performance recommendations if you have not already done so. That wakes up the lower rpm ranges in particular.
With a 454 4 spd you should have no bog and that car should scoot.! With any kind of rear gear. Get the distrib tuned "right"
Le Mans Master
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From: Cool Northern Michigan
A sloppy chain will retard the cam from 1 -4 degrees depending on the severity of the stretch. What that does is, makes your car run like a dog with no low-end grunt.
But will also scream at the higher RPMs.
Last edited by HeadsU.P.; Apr 15, 2021 at 07:05 PM.
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Heel & Toe
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Just curious. What is the history, mileage and age of your timing chain set?
A sloppy chain will retard the cam from 1 -4 degrees depending on the severity of the stretch. What that does is, makes your car run like a dog with no low-end grunt.
But will also scream at the higher RPMs.
A sloppy chain will retard the cam from 1 -4 degrees depending on the severity of the stretch. What that does is, makes your car run like a dog with no low-end grunt.
But will also scream at the higher RPMs.
Le Mans Master
Joined: Aug 2017
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From: Cool Northern Michigan
Ok. A fairly simple test to see if the timing chain has excess slack is to:
Remove 3-4 plug wires from dizzy cap and lay cap off to the side.
If you can get a ratchet / breaker bar on the harmonic balance bolt, turn the crank a bit clockwise noting the rotor.
Then reverse the crank and watch the rotor again.
If it took several crank degrees rotation for the rotor to move, you have a sloppy chain.
Remove 3-4 plug wires from dizzy cap and lay cap off to the side.
If you can get a ratchet / breaker bar on the harmonic balance bolt, turn the crank a bit clockwise noting the rotor.
Then reverse the crank and watch the rotor again.
If it took several crank degrees rotation for the rotor to move, you have a sloppy chain.
Last edited by HeadsU.P.; Apr 15, 2021 at 07:56 PM.
Race Director
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Automatic I presume? If you can force your RPM higher, does the car behave like it does in 3rd gear?
Perhaps you can give us some more info (RPMs, tune/timing, etc) to separate the transmission from the engine. if you aren't seeing 3000 RPM until 3rd gear, your secondaries probably aren't opening. Otherwise, is there a trans-related vacuum leak that could cause issues?
Perhaps you can give us some more info (RPMs, tune/timing, etc) to separate the transmission from the engine. if you aren't seeing 3000 RPM until 3rd gear, your secondaries probably aren't opening. Otherwise, is there a trans-related vacuum leak that could cause issues?
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Heel & Toe
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***update***
I would to thank everyone that responded to my post a few months ago. I put a lighter spring set in the distributor, which helped a lot!! I found out that 3 of my spark plug wires were burnt through so only running on 5 cylinders. Since then I bought ceramic coated wires plus put on heat shield sleeves. I took off the headers and found the gaskets were deteriorated causing exhaust leak. I decided to back to stock manifolds. And lastly I put a brand new exhaust system on. Needless to say it's running really well and once I get the smaller stuff tuned in, she's going to be a monster!!!
thanks again for everyone's insight.
thanks again for everyone's insight.