383 help!!!! our motor combo needs suggestions

[694life]

My buddys got a 69 charger with a 383 bored 40 over,forged crank, flat top forged pistons, 509 cam degreed and installed straight up,906 heads with 2.08 in/ 1.75 ex valves, 3200 converter 4.10 gears holley street dominater single plane intake with a 980 cfm carb 29 inch tall mt drag radials. car went 13.45 @ 102 with a 2.02 60 ft no wheel spin. I dont know mopar and he doesnt use computers. I think this thing is setup for higher rpm and we cant get anything off the line. We want this car to run 11.80's or at least low 12's. Please help us make this thing fly like mopars do. Not opposed to starting over with a new combo.

[Brightyellow69rtse]

Good intake choice imo.I think the carb is way too big. Others will chime in

[randy73]

I agree, that is a lot of carb for a 383, also you do not mention if the heads have been modded or compression ratio.

stroked?

what tranny, has it been rebuilt lately. seen rebuilt tranny's that slip.

What size primaries on the headers? (assuming you have headers)

[694life]

1 3/4 primaries motor is supposed to be 10.5 -1 but I dont know for sure. I know the heads are stock except larger valves. Trans was rebuilt 6 months ago because third was slippin and 3200 converter installed. car ran 13.65@ 101 before trans and carb was sent out to Nickerson performance and was supposedly built for this combo. car now runs 13.45 @ 102. We felt it shoulda ran a 12.8 or so. after about 100ft the thing rips but nothing till 100ft

[randy73]

Have you checked to see if you are running rich or lean?

That is WAY to much carb for stock 383 heads, my Cuda w/383 is running 750cfm and that is almost to much and my heads have had port work and valve job.

Have you tuned the carb?

Bet you will find you are running way rich and what are the specs for the cam?

[c00nhunterjoe]

Tires are too tall for the combo. I can cut 2.0 60 ft's with my similar build 383 on bare bones street tires and a 4 speed. Drop to a 26 inch tire and it should get more violent off the line.

Stalling at 3200 is going t limit you as well in this engine. The cam is just starting to make power there. Need to stall at 4500for peak et's on that 383 but you'll lose driveability.

Carb is too big. 750 is a good streetable size for that build 383.

The size valves you listed are stock size, either way, unported heads will limit you in the end, but there is mid 12's in your current engine.

Id start with shorter tires and a 750 holley. What is his total timing set at? Those 3 adjustments should have you knocking on a 12 sec passes door. Remember the 383 will make power at higher rpm's then the 440's will, also shift into second a little higher in rpm then usual to keep it from bogging down after then shift.

[c00nhunterjoe]

Have you checked to see if you are running rich or lean?

That is WAY to much carb for stock 383 heads, my Cuda w/383 is running 750cfm and that is almost to much and my heads have had port work and valve job.

Have you tuned the carb?

Bet you will find you are running way rich and what are the specs for the cam?

509 cam should be .509 lift, 292 adv. Spec at .050 varies depending on what manufacture it is. Typicly 242-248.

A 383 with ported heads will thrive on an 850, stock heads a 750 is perfect. Plenty of dyno sheets and articles to back it up. An 850 on stock heads will actually make more power then th 750 for the track, but the 750 will behave better on the street. Its all about tuning.  In any case, this particular 383 is overcarbed

[Chryco Psycho]

The 509 cam is far from a good choice , too much duration & not a whole lot of lift , you could gain a lot with just that .
IF you have to stay hyd look at the Voodoo cams , I would go to a Solid flat tappet at least or a roller ,I would look for a cam with 2600 - 6600 powerband to work with the converter you have . The Lunati 60405 is a good fit , or call Lunati .
The carb is on the large side but may be  OK with enough converter gear & rpm .
The big gain would be in 60' you need to trim off .4 in 60' , this will make a huge difference in overall times , you say you are not spining the tires which is good , But why , is the converter working properly ? removing weight or moving it rearward , stiffening &  clamping the front section of the leafs will help transfer more power to the chassis  .

[c00nhunterjoe]

Chris,  he is running .040 flat tops you can't go more then 510 lift based on that. Unless he is running the high dollar pistons with the valve reliefs there will be contact. That's why I said drop down in carb and tire height rather then tear into the bottom end.

If he has the valve reliefs then I agree, go solid cam with .550 lift 

[BSB67]

Is it tuned for what it is?  If it is, you're missing 100 hp to reach your goal.  You simply are not making enough power.  The car has to go at least 112 mph to get to your goal, and there is no carb/converter/tire that will even get you close.

So the question is: should this motor be making 100 more hp?  I don't know without the build specs and car weight. 11.8s for a 383 i not a walk in the park.

Check the cylinder pressure, and check the fuel pressure at the carb at full throttle (like through the traps) and report back.

If I were a betting man, your cylinder pressure in is the toilet

[c00nhunterjoe]

Is it tuned for what it is?  If it is, you're missing 100 hp to reach your goal.  You simply are not making enough power.  The car has to go at least 112 mph to get to your goal, and there is no carb/converter/tire that will even get you close.

So the question is: should this motor be making 100 more hp?  I don't know without the build specs and car weight. 11.8s for a 383 i not a walk in the park.

Check the cylinder pressure, and check the fuel pressure at the carb at full throttle (like through the traps) and report back.

If I were a betting man, your cylinder pressure in is the toilet

100 hp more? I doubt it. His build nearly mirrors mine but I don't have big valves and I'm running a 750 holley. I have hit 107 in the 1\4 and have seen mid 12's but I am maxed out on my engine as it is built.

In theory he should be able to make the same ets as 8I do

[BSB67]

Is it tuned for what it is?  If it is, you're missing 100 hp to reach your goal.  You simply are not making enough power.  The car has to go at least 112 mph to get to your goal, and there is no carb/converter/tire that will even get you close.

So the question is: should this motor be making 100 more hp?  I don't know without the build specs and car weight. 11.8s for a 383 i not a walk in the park.

Check the cylinder pressure, and check the fuel pressure at the carb at full throttle (like through the traps) and report back.

If I were a betting man, your cylinder pressure in is the toilet

100 hp more? I doubt it. His build nearly mirrors mine but I don't have big valves and I'm running a 750 holley. I have hit 107 in the 1\4 and have seen mid 12's but I am maxed out on my engine as it is built.

In theory he should be able to make the same ets as 8I do

Right, you're making 50 more hp than him, at mid 12s at 107, so another 50 more to go 11.8 at 112. Assuming about the same weight

[c00nhunterjoe]

/quote]

Right, you're making 50 more hp than him, at mid 12s at 107, so another 50 more to go 11.8 at 112. Assuming about the same weight

Exactly. He should be making more power then me. I'm running stock heads where his have bigger valves, and he has a "better" intake then me. I'm running the old school torker 383 on mine. the only thing that would give me a weight advantage is no spare tire or jack..... the rest of the car is bone stock, I weigh 240 lbs.   I'm also running 4.30's with a 28 inch street tire

All that said I feel its overcarbed and over tired.4.10's on a 29 inch tire launching at 3000 rpm isn't going to to be impessive behind that build.

[firefighter3931]

If I were a betting man, your cylinder pressure in is the toilet

Best answer yet 

To make the 509 work in that combo he needs at least 12:1 compression and 4500-5000 stall + 4.56 gears to make it ET best.

Translation ; it's way overcammed, under stalled and under geared 

Fwiw, my old 446 made 535hp/540tq and the car had a 4200 stall/4.10/29.5 M/T Drag Radial. Typical performance was 11.80's @ 114 with a personal best of 11.68 @116.5 in Mineshaft air (DA was -300ft). 



Ron

[BSB67]

/quote]

Right, you're making 50 more hp than him, at mid 12s at 107, so another 50 more to go 11.8 at 112. Assuming about the same weight

Exactly. He should be making more power then me. I'm running stock heads where his have bigger valves, and he has a "better" intake then me. I'm running the old school torker 383 on mine. the only thing that would give me a weight advantage is no spare tire or jack..... the rest of the car is bone stock, I weigh 240 lbs.   I'm also running 4.30's with a 28 inch street tire

All that said I feel its overcarbed and over tired.4.10's on a 29 inch tire launching at 3000 rpm isn't going to to be impessive behind that build.

But he is not making more power.  I have no idea what is in his motor, nor does he.  I don't know if he should be making 300 hp or 450 hp.  I do know that he is actually short 100 hp or more to get to his goal.    Suspension changes may reduce the et a little, but will not add power, or effect the mph.

[694life]

Holy sniiickies lol. timing is set up total 40deg.  Ok so lets start with the cylinder pressure. what should it be at 150ish psi? As far as the carb it was done by Nickerson performance and the thing flys when rolling and never hesitates and has instant snap on the throttle. We were told by Nickerson to get the digital ignition box and lock the timing out at 40. Im not disagreeing about it being over carbed but the car had a holley 750dp and the car ran a 13.65. So its quicker now and revs, runs, and starts better then ever with the new carb. I was thinking after reading on here alot that the cam is not right for the setup. Seems like the only thing that sucks is the soft 2.01 60 ft's

Firefighter... what cam do you suggest we go to with for the combo we have. would like to change as little as possible thats if the cylinder pressure checks out?

Also what about a little spray of the line? the car runs great, starts, drives, and sounds mean as hell perhaps a 100hp shot outta the hole?

[c00nhunterjoe]

Before changing cams you need to figure out what pistons are in it. You said flat tops. Do they have valve reliefs or are they true flat tops. If they are flat tops without reliefs then you are seriously limited to ca choices and won't be able to go more then the .510 lift you have now.

[694life]

No valve reliefs  What are our options in cams is it worth it to do a full rebuild maybe a 43? stroker setup?

[c00nhunterjoe]

Do you by chance know the brand and part number of the pistons used?

What is the goal et for the car? Strictly a track car or street car as well?

In my opinion, your current long block is good for mid 12's at its peak, no more. If you want to dip into the 1's you are going to have to make major changes to the engine or as you suggested before, spray it.

[694life]

no part #'s for pistons. Its a street car mid 12's all motor would be awesome. A little spray once its all worked out prolly will happen. Do you have a cam recommendation for this thing. I know its hard without the motor specs but i few hundred $$ and a few hours is worth it for now since the 509 surely isnt workin for us. In time a 440 or a stroker 383 will be built with the right combo of heads and such. so for now 12.50's would be great!!

[c00nhunterjoe]

I personaly like the "509" I run an old racer brown grind that's a little more aggressive then the mp grind. Mine is .510 lift, 292 adv, 248@ .050. It may not be the best cam in the world, but it performs well in my engine and the sound is awesome. Others will chime in on how its a bad choice. To each their own I suppose.

Remember you are limited to the 500 lift cams, if anything you would step down in duration, but keep the lift.I have heard good things about the lunati cam from people on this site but I have not personally used them. I have had good results from comp cams extreme energy line as well as isky cams. Isky makes a great product and has an excellnt tech support line if you have questions.

If this were my car I would run your current engine and change tires to a 26 inch tall sticky.

[c00nhunterjoe]

If you were to change cams:

Lunati voodoo- 60302
Comp xtreme energy- xe274h
Racer brown- too many choices to list in the .500 lift, mild duration area. Jim has some really nice grinds that take advantage of our large diameter lifter by having fast ramp angles. Givehim a call.
Isky- same thing, best to call their tech support as they have tons of choices.

[firefighter3931]

I was thinking after reading on here alot that the cam is not right for the setup. Seems like the only thing that sucks is the soft 2.01 60 ft's

Firefighter... what cam do you suggest we go to with for the combo we have. would like to change as little as possible thats if the cylinder pressure checks out?

Also what about a little spray of the line? the car runs great, starts, drives, and sounds mean as hell perhaps a 100hp shot outta the hole?

The current 509 cam is the reason it's not 60 fting like it should. In a 383ci build that cam won't come on strong until 4200-4500 rpm and you have a 3200 stall....hence the mismatch 

You need to pull 20* of duration @.050 valve lift out for it to make power where you need it 

The Comp XE274H or the Lunati VooDoo 303 would be my choice if wanting to stay with a hydraulic but if you want to make it sing i would go with the Comp XS274S which is an extreme energy solid flat tappet grind. This would require an adjustable valvetrain of course.



Ron

[694life]

thanks guys for all the help so far!! This site is awesome tons of info here !!! So before we pull the trigger on a voodoo 60303. will this work with the .513 exhaust lift and stock 906 heads with flattops. I heard .510 max? i am having trouble finding specs on the comp cams you suggested. Is this holley intake good for these cams? does anything else need to change?

[694life]

Whats it cost to go to a solid cam? What needs to change?