What to do?

[moparbob75]

Maybe you guys can help me out my runner has 383 stock bottom end with flat top pistons aero head 452 heads with bigger valves the Hughes whiplash cam performer RPM intake and 750edel carb. When I stomp on it shouldn't it just get out of control? I can't hardly get it to spin a tire. I'm thinkin one of two things or both, maybe my timin off how do I set timing with a light and what should it be set at? And my gears are 323 and I have 275/60/15 tires on back maybe they too big? Any help would be hugely appreciated

 

[70rr-brian]

You know what kinda power that motor is putting out? I would guess 375ish? Even with 3.23's you should be able to get it to spin pretty good. Unless you have some really sticky tires on it.

I run the same size tires as you with a stroker with 620lbs of torque and without brake torqing could explode them before I ever got them to stop smoking if I wanted to. Back before the stroker with the stock 383 and 3.55's it would spin them...but nothing outrageous. Like maybe a 15 yard patch.

That said, is there any stumble off idle? I assume it is a 727 cause if not then you have a serious problem if popping the clutch doesn't do the trick!

 

[moparbob75]

Yea it's a 727 I not sure about the horsepower that would be my guess it runs good goin down road just seems lil doggy at take off

 

[super-bee_ski]

You wont beleive this BUT:
The guy I bought my 70' Superbee, 383 auto had the same issue. Turned out to be a "E" in the 5th digit of the car (I think) and the car was a Los Ageles compatable car reduced in power for LA County in 1970. HONEST!
It had 2 wires off the distributor and some other power reducing MOD.
I'm NOT saying this is your same problem BUT it was mine. Cuda Bob from Lancaster CA helped me out.

 

[rolling_Thunder]

I would bet your issue is somewhere in either the timing or the carb. The timing I usually set around 36* total advance --- The BB distributor usually has I believe 22-24* of timing in it between mechanical and vac advance. So I usually set base timing to 10-12* BTDC and have good luck going that route.

The edelbrock carb (depending on model) is set up from the factory for economy and not power... It is my experience that these models usually have an off idle stumble that results in poor off the line performance. The carb can be adjusted using the linkage rod on the front driver's side as well as a larger squirter.

Another issue could be the camshaft... I am not a huge fan of the Hughes cams myself and have limited experience with them because of this - but if it went flat or was ground on the wrong LSA it could be throwing off the timing aspect of the engine...

The 383 was not known to be a torque monster but if my old stock 318 auto could smoke the 275/60/15s on my Charger without a problem you shouldn't have an issue at all.

 

[Hemi Rebel]

Do you have a stall converter? If so what rpm will it flash to. You didnt say what cam you have exactly so i dont know what rpm range it is, but if it does not come on til say 3 grand, and you have a converter that only stalls to say 1800, its going to be a turd down low. Provided the timing is set right, with the right converter, you should be able to fry the tires off. A good friend of mine races a 68 RR with a mild 383. With slicks, it jerks the left front tire when it launches. Set up right they can make some torque. And dump that edelbrock carb. That crab is good for grampas 350 chevy powered street. Rod but not somethibg you want to make real power with. Not that the edelbrock cant be workes, but their are better carbs purpose built for the performance you want

 

[tpodwdog]

275's are a big tire...and the 3:23's aint helping that situation..

my 70 runner has a stock 383 4 bbl - 3:55's...and 255-60 tires....it hardly will spin em off...but i can get it to do it on dry pavement if i really try ....i have extremely sticky tires also. id say its more gearing with the automatic....if it is an automatic.

....if you have points ...make sure they are set also....should be set at 30 (.018) degrees of dwell......one degree of dwell will change one degree of timing. set dwell,,,then timing !

 

[moparbob75]

Ok thanks everybody. The cam is supposed to be idle and up power range. The cam sounds mean its on you tube for those that not heard my car. I have been debating about a Holley carb just not had much luck with them. The distributor has been changed to electronic, and car is st Louis built. The converter is a hemi converter that's about all I know. It will sit at a stop light and not lunge. I'm goin to mess with the timing when I get home next week and maybe a carb change? Any suggestions? I have never messed with timing with a light before my buddies always timed them by ear. So hope not dumb question but can you all tell me step by step how to do that?

 

[moparbob75]

I've also thought about a six pack setup what's everybody's input on those?

 

[Cranky]

Lots of info on 'how to use a timing light' on the net and even youtube has vids but basically, you locate your timing marks on the balancer and timing chain cover, hook up a timing light to #1 plug and the power leads to the battery, unplug the vacuum line from the advance pod on the distributor and plug the line, fire up the engine and point the light at the marks and squeeze the trigger. It's pretty simple. I also like to use a vacuum gauge and adjust the carb for the smoothest idle with the highest vacuum. I like to set my timing at least 10 degrees advanced at idle and go from there and usually end up with 12-15 on most but there have been times with I've had more. Give the engine what it likes. Btw, who put this package together and did they just install the cam and align the dots or use a degree wheel for the installation? Production tolerances can stack up on the parts so if the cam was ground off a couple of degrees, and the sprockets were not stamped on the money, the cam could be off several degrees and there's no way to know it when using the dot method. Anyways, work on what you have and try to get it to run good before messing with a carb change. If you are confident that the Eddy carb is good, work with it first. Sounds to me like you don't have much experience with cars and going to a 6 pack is another step up the ladder of experience imo.

 

[moparbob75]

Well I'm not the smartest but I am mechanically inclined give me time with something and I will figure it out. The combo is pretty much what I research and talk to other people about it. But there is always people that say I wouldn't have done that or you should do this but you don't know unless you try it. I will do some experimenting when I'm home and let you all know what I come up with. Yes the six pack thing more or less just to say I got one

 

[super-bee_ski]

Compression Check performed?

moparbob75:
Check compression yet? My 70 Superbee 383 had same symptoms. It was multiple issues BUT one truly stood out; Low compression in ALL cylinders. Did you perform a compression check?

 

[moparbob75]

No I have not

 

[moparbob75]

Wha

 

[moparbob75]

Whoops thumb got trigger happy. What should compression read?

 

[super-bee_ski]

The compression on my 1970 383 is between 135 to 145 psi , engine cold.
Those old 383s had a big bore and shorter stroke, making them REV quickly (a positive atribute for a race motor) and some of them got tired needing re-builds. Checking compression is one place to start looking.

 

[moparbob75]

Well it's been rebuilt about 2 years ago don't even have 5000 miles on it

 

[Kern Dog]

You didn't list the cam specs. This is very important. I'd expect the "whiplash" cam series to have more than one cam grind.
There is more to performance than high compression and a lopey cam. You may be onto something, your timing may be partly to blame. Forget what the factory specs were. they were a compromise between economy and emissions. racers knew that back in the day and they advanced the timing to gain more power. A medium to high performance V8 will respond to 12 or more degrees BTDC. I have 17 degrees in the Charger 493. I had to limit total timing to 32 to avoid detonation on 91 octane gas.
Another factor is the torque converter.... if it stalls too low, it will have the effect of a car with a manual trans starting off in 2nd gear.

 

[moparbob75]

Ok the specs on the cam

Intake valve lift 1.5 is 518
Exhaust lift is same
Intake dur @ .050 229
Exhaust dur @ .050 242
Lobe sep angle 107
Intake open @ .050 12.5 BTC
Exhaust open is 53 BBC
Intake closing @ .050 36.5 ABC
Exhaust closing is 9 ATC
Sweet spot RPM 1800-5200
Now maybe you all can tell me the right combo for my car like I say the car runs good idling and goin down road and that cam sound really mean and loud maybe I got wrong combo maybe I'm just missing something like wrong converter I will admit cam and converters always had me screwed up. Anything else you need to know please feel free to ask

 

[moparbob75]

Guess from what I been reading maybe that's my problem, but wouldn't I need a converter around the 2500 range? What does hemi converter stall at?