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Discussion Starter #1
I'm currently running a 638cast 350 with a 1408 edelbrock carb it has a mild performance cam and springs to match it still seems sluggish and is completely dead in second gear(700r4) what can I add redo or replace that's going to be the best bang for my buck?
 

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Correct ignition timing can make a huge difference.:yes:
 

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aluminum heads and a larger cam will give you the best bang for your buck....cnat use nos all the time:no:
 

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its a toss up really. Your right nos cant be used at all times. But head and cam will require a ton of upfront money and additional money towards mpg loss.

Nitrous will kill the life of an engine over time.

But what a rush. what gears do you have. Some 373s or 411 will wake that up as well
 

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what are u running for rear gears, especially with the OD tranny, you can get away with a little deeper than those of us running 3 speeds. Nuttin like say a 3.08 steppin up to a 4:11 to wake that car up :yes: while still retaining streetability being able to use the OD. pretty inexpensive swap as well, now it wont add anymore power so to speak, but will move what power u have into a different rpm range down lower where more "street driving" is taking place.

If you think something is wrong and power went away...timing would be my first lookie see, vaccuum leaks, and so on down the line...

if your looking to upgrade MORE power and not move what power u have around in the rpm range, definitely heads, and cam...but bigger doesnt always necessarily MEAN better...a properly matched motor will usually outperform just stuffing the biggest and baddest of everything in your car...or n2o or udder power adders can wake up a motor rather well....annnnnd usually the more stock a motor the bigger differences you will see....my 2 cents
 

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I'm currently running a 638cast 350 with a 1408 edelbrock carb it has a mild performance cam and springs to match it still seems sluggish and is completely dead in second gear(700r4) what can I add redo or replace that's going to be the best bang for my buck?
10" converter with 2,400 - 2,600 RPM flash stall speed, 3.73 gear, 4776 or 4777 Holley carb, and a properly curved advance mechanism in the distributor. You will not believe the difference in performance and drivability.
 

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Discussion Starter #10 (Edited)
I'm not 100% on the rear end gears I'm trying to find out from the previous owner. It seems like it's lost power over the last year I've owned it. If I ever give it full gas it seems to bog down quite a bit. I've tuned the carb hundreds of times but it always seems to need re-tuned. The previous owner left it in some major work needing to be done. I'm not against putting nitrous in as eventually I want to swap in a ls 5.3l to add fuel economy and power, but with nitrious I've heard some horror stories and like said earlier it's not always there. And I'm located in the surprise/Waddell area:yes:
 

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Since the engine is losing power it's time to dig a little deeper.

Check for vacuum leaks and check manifold vacuum using a vacuum gauge. If manifold vacuum is erratic then you could have one or more leaks, burned valves, weak valve springs, valve adjustment issues, and/or lifter issues.

Make sure the distributor hasn't moved.

Check the mechanical advance mechanism to make sure that it hasn't seized.

Remove once of the valve covers and watch the rocker arms as you turn the engine over by hand back and forth. Verify how far you're moving the engine by watching the timing mark on the damper against the timing tab. If you can move the crankshaft more than 4 - 6 degrees before the valvetrain begins moving then you probably have a timing chain that's worn out. A worn timing chain will lead to retarded camshaft timing which will contribute to a loss of low-speed power production.

Run a compression test and cylinder leak-down test.
 

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Discussion Starter #15
Huge typo batman not about ls but with nitrous if I could afford the upfront cost I'd do an ls swap in a heartbeat. I figured when he said 3.50 I died a little inside....
 

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While you're at it verify that the timing mark on the damper lines up with zero on the timing tab when the engine is at #1 TDC. The outer ring on a stock harmonic damper can spin over time which will throw off your timing marks. This inevitably leads to incorrect ignition timing settings. If the elastomer between the inner damper hub and outer damper ring is cracked and pushing out from between the two damper pieces then there's a good chance the outer ring has moved.
 
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