383 build no power

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72golddustermike

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northeast arkansas
Engine was rebuilt when I got it here are the specs

70 challenger
9:7 compression
Old 284 484 cam
2000 stall
3.23 gear
215/70 14 tire
Factory 600 holley
Factory intake
HP manifolds

Car will not even think about spinning a tire. it has no power at all. I have a pertronix 3 distributor that was curved by don at fbo he curved it to be all in at 3200 could this be the problem, I am almost ready to just yank the cam out and replace it with one that would suit me its a show/cruiser not looking for high rpm. What do you guys think about these cams

http://www.lunatipower.com/Product.aspx?id=2335
http://www.compperformancegroupstor...uct_Code=21-215-4&Category_Code=WDGCAMhydFTHE
http://www.compperformancegroupstor...uct_Code=21-222-4&Category_Code=WDGCAMhydFTXE
http://www.summitracing.com/parts/dcc-4452783ae/overview/

any suggestion
 
That cam is a killer on low compression engines and needs a stall converter (3000+) with higher compression in a 383. You can help it some by advancing the cam and using a dual plane intake as mentioned. Lower gears would also improve the feel.
 
Strikes me as a mismatch of parts. Any 383 should burn tires. Even a low compression one.

That cam might be too big for your setup. What heads are you running? What intake? What happens when you try to burn the tires? Does it just stand up and kinda sit there? Like it wants to but can't quite? Or does it not even try?

Before you start looking at cams. Look at the whole setup. Pick thing's that will run together, not against each other.
 
Have you verified true TDC?

Have you checked/degreed the cam to see where it's timed?

Then what is your ignition timing settings?


I would suggest to make sure what you have has been properly set up before spending money replacing parts... Verify the basics first...
 
^^Yup. Verify true TDC

Then find out where ignition timing is

Then investigate A/F ratio

Investigate cam timing

What do you have for exhaust / headers?
 
600 Holley..

Have you verified the accelerator pump linkage clearance? .015" - .017" at wide open throttle....

How about the throttle cable? Is there any slack in it? loosen the nut and slide it back until all of the slack is out of the cable...
 
Can't spin 215s? Sad day for you.
Yeah that cam want's some compression, or a bunch more stall.And as always "put some initial timing into it"
9.7 Scr should get her moving tho.
Have you verified the TC stall? The carb going WOT with the pedal?the cranking compression?the TDC mark?

So, as others have mentioned; if it's not in the throttle cable not going WOT,or lazy timing, you will be shopping for a TC.Try it again with reduced traction; such as in a water puddle, or on dirtysmooth-concrete.If it won't spin up in the puddle, I think the compression is not where it should be.
How is it if you stomp it at 3000rpm? 4000?

I've tuned teener Challengers with 3.55s that absolutely destroyed 275s from take-off.So cheer up;theres hope for your 383
 
Stock 383HP Intake and exhaust and Holley 600 Timing is at 30 at idle per FBO instructions 18 Intial 12 vacuum Advance on constant manifold. I gave him my Tire,Gear ,cam Size and he set up a new Pertronix Distributor up for me. Said best curve would be all in at 3200 I thik he put 16 mechanical advance in it. Throttle going all the way back and used paper clip to verify four barrel opens.Torque converter is a new dacco 764 from auto zone
 
I had a similar cam in a 383 in a Polara with stock intake and manifolds and it was a dog. It would wind up tight but just too much for it.
 
need at least 3500 stall converter and at least 3.55 in the rear.
 
72golddustermike said:
Stock 383HP Intake and exhaust and Holley 600 Timing is at 30 at idle per FBO instructions 18 Intial 12 vacuum Advance on constant manifold. I gave him my Tire,Gear ,cam Size and he set up a new Pertronix Distributor up for me. Said best curve would be all in at 3200 I thik he put 16 mechanical advance in it. Throttle going all the way back and used paper clip to verify four barrel opens.Torque converter is a new dacco 764 from auto zone
Click to expand...

Is that "all the way back" using the gas-pedal?
Is that Holley a Vacuum Secondary?
You need more timing. Put the light on it, rev it up until it reaches a maximum number of degrees and add 200 rpm. That number might be 3200rpm or 3600 or 4200, or whatever rpm.From now on, that is the rpm that you will set your power-timing at. Next disconnect the vacuum advance and plug the carb-port, and re-set your power-timing to 36 degrees. Never mind what it is at idle. Then roadtest it to be sure it does not detonate under full power. Then run it up to 65mph in 2nd, at various throttle settings, and make sure again that she is detonation-free.I will not buy you a new engine if you melt it down.Finally, repeat the tirespin test.
But before I would do any of that, I would do a compression test, and a stall test.
If the compression is down, I would do a leakdown test. If the valves are leaking there are other tests.

FWIW; that cam should not need the Vcan hooked to manifold vacuum. It may produce much better part throttle/low load results when hooked to the timed spark-port.And if there really is 16 mechanical in the dizzy, after the reset there will be 18+4 =22initial, plus the 12 vacuum equals 34 of idle timing. This will probably be too much. The 22 will be just right,all by itself. I've tuned bigger cams in smaller engines with way less than 22.
 
do a compression test on all 8 cylinders. and look at the spark plugs while they are out. I think your combo is not bad. needs tuning.
 
I had that cam in a 68 340 2.02 headed 3.91 rear with a "Boss Hogg" 2800 stall, roast the 215's at will. That was with a 625 Demon and an STR-12. 3.23 rear with a heavier car may hurt and a stock convertor will hurt.
 
Gear,converter,& something bigger carb wise.(750-3310 Holley,or a similar size AFB)..Tune that accelerator pump circuit...
 
It will actually have better drivability with a stock 2bbl set on it. Did that on a 78 New Yorker with a 400 somebody over cammed and it drove remarkably well and was hard to keep below 80 on the highway..... I did drill bypass holes in the throttle plates.
 
bigger carb wont help off idle performance. Buddy had a '66 421 Pontiac that had a puny 575 cfm Carter on it, monster off the line. That boat would burn rubber for seconds. Unless its a TQ or a QJ with micro primaries.
 
Cam way too big,not enough comp. converter too tight,probably not degreed plus exh manifolds.Its in the combo this is in left field.Its not the intake, carb or timing. THE comp 262 or the voodoo.
 
Had the lunati in a stock build. Works well for a street cruiser.

[ame="https://www.youtube.com/watch?v=Wb13N9USp8I"]'68 Dart Holeshot - YouTube[/ame]
 
pishta said:
bigger carb wont help off idle performance. Buddy had a '66 421 Pontiac that had a puny 575 cfm Carter on it, monster off the line. That boat would burn rubber for seconds. Unless its a TQ or a QJ with micro primaries.
Click to expand...

Pishta,just curious: How big a cam,did that 421 have?. Feed that cam some idle/off idle/transfer slot/accelerator pump,works sweet.(Been there,done that). I just don't see a .484 Purple shaft,tuning in easy for a beginner(Jmo..)
 
with tuning, the combo will still be a slug below 3000rpm, add some gear and a 3500 stall converter to wake it up down low. headers and 3310 holley would be nice too.
sorry to be so brutal, but I've been where your at with the 383.
 
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