What Carb for a D-1SC Procharged 383 ???

[Tim_in_NC]

Hi Guys,

I've begun specing out my 383 stroker and will be adding a Carbed Procharger ...

I'm planning on going with a 750 Holley but I'm not sure as to which part number is needed? Double Pumper? Vac? etc...

Can someone help me with which carb works best in the blow thru supercharged environment...

Thanks,
TIM

[camcojb]

I have heard of people using vacuum secondaries, but I would recommend a double pumper. A 750 will support 750-800 HP no problem. I have used Scott at SD Concepts a couple of times with the carb mods and both were spot-on. Do NOT try to mod them according to ProCharger, send them to someone who is familiar with blow through systems.

Jody

[WELTERRACER]

750 DP... just buy it from ATI ... then all you will have to do is jet and tune it..

[camcojb]

750 DP... just buy it from ATI ... then all you will have to do is jet and tune it..

I would STRONGLY suggest NOT getting it from ATI. Great blowers but their carb mods are severely lacking.

Jody

[WELTERRACER]

I agree it sucks tuning carbs... but if you buy the Holley tuning guide and read it about 10 times you can learn alot about them and not have to pay someone $450 to do it for you..

FYI... my carb i got from ATI is a 750 DP and all i had to do is change the jets to 80 and 90s like ATI told me and swap out the power valve and it runs almost perfect!

You should run a 750 on your 383

[Tim_in_NC]

Thanks guys...

Would just a basic 750 Holley Double Pumper work?

What's Scott's usual fee to transform the carb?

[camcojb]

I agree it sucks tuning carbs... but if you buy the Holley tuning guide and read it about 10 times you can learn alot about them and not have to pay someone $450 to do it for you..

FYI... my carb i got from ATI is a 750 DP and all i had to do is change the jets to 80 and 90s like ATI told me and swap out the power valve and it runs almost perfect!

You should run a 750 on your 383

Doesn't suck to tune a carb. Sucks to listen to ATI tell you that jetting and power valve changes will make a stock 750 run good on a Procharged vehicle. You also need metering block and air bleed changes 99% of the time, especially with higher boost. Also most of the time a different booster is used. None of those mods can be done at home by the average guy.

Believe me, I tried. Learned my lesson. I could get it to idle and cruise good but suck at more agressive or WOT driving. Or I could get the WOT good but the transition, cruise, etc. wasn't right. Then I learned about all the other mods that were needed in nearly every case. So I spend my $350 or so with Scott if I'm doing a blow-through carb. Best money I've ever spent.

Jody

[Blown353]

Another recommendation for Scott @ SDCE.

Jody turned me onto Scott, and he did my carb (when I was running blowthrough.) It's not just tuning, there are several internal mods required to make it run smooth at all the areas you drive in.

With my carb that Scott modded (Demon 750 DP) I only had to barely tweak idle speed and mixture. It was spot-on across the board with a rock-steady A/F ratio right out of the box. After I got it, I tried changing jets, airbleeds, power valves, etc to get a little bit more out of it but I always ended up right back how Scott shipped it to me. He needs to know every last detail about your combo to work his magic, but it's worth it.

Another important thing is the carb hat. These can make or more than often break the combo, as 90% of of the hats out there are junk and will tend to "favor" one part of the carb, causing you to stagger jet, some cylinders running lean, or even just falling on its face when you nail it. There are a few good ones, and many, many bad ones. Scott has done some pretty extensive airflow testing of many hats, using spacers, how they're clocked, internal baffles, etc, and watching the air and fuel flow through each barrel of the carb.

Troy

[WELTERRACER]

I agree if you have an unlimited budget... Pay someone else to do it...

Myself i cannot afford to pay someone else to do work for me... THerefore i learn to do it myself..

A standard holley will work but it needs Good nonstick gaskets and special floats that can be purchased from ATI for $35.. Jet front and rear jets 10 sizes over what you would normally use!

[camcojb]

I agree if you have an unlimited budget... Pay someone else to do it...

Myself i cannot afford to pay someone else to do work for me... THerefore i learn to do it myself..

A standard holley will work but it needs Good nonstick gaskets and special floats that can be purchased from ATI for $35.. Jet front and rear jets 10 sizes over what you would normally use!

I think we're misunderstanding each other. On my ProCharger blow through carb setups (I've done three with carbs) NONE of them would run correctly with just float and jet changes. ALL of them needed the metering blocks re-worked and air bleeds re-sized, and one also needed a booster change to run correctly. None of those things can be done at home by regular people regardless of budget.

The mods you are quoting are what ATI tells you to do. Unfortunately in 90% of the cases it is completely untrue, you have to go much further into the mods to make it run correctly. If you search the blow through boards on the net you'll find dozens of threads about the carb mods needed to run right, and jetting and float changes alone don't get you there in almost all cases.

I am not arguing with you but I am really trying to save someone a lot of grief trying to get their ProCharger system set up and run correctly. I already went through this on my first kit and kept listening to ATI tell me that's all I needed to do and nobody else is having any problems. Then I found an online board that showed a ton of their customers all complaining about the driveability with their recommended mods. I was thrilled to get the car running perfect for only $325.


Jody

[ProdigyCustoms]

Jody, is it a case where the ATI carb is OK for little boost, 6LBS or so, but not for 12LBS? Or is A/F ratio screwed up even at little boost, but not as apparent?
We just did a 16 / 22 LB F2r and had the carb done by someone ATI recomended, and still had to change the squirter and cam, amoung other things. For the money, I was not impressed with the carb. It was not your guy.

[camcojb]

Jody, is it a case where the ATI carb is OK for little boost, 6LBS or so, but not for 12LBS? Or is A/F ratio screwed up even at little boost, but not as apparent?
We just did a 16 / 22 LB F2r and had the carb done by someone ATI recomended, and still had to change the squirter and cam, amoung other things. For the money, I was not impressed with the carb. It was not your guy.

Frank,

It could be. I've never run less than 10 psi so I can't say for sure. What I do know is I could get WOT pretty good but the idle and cruise areas sucked. If I jetted it down to clear those up it wouldn't run at WOT. This is where metering block and air bleed work is crucial. I mean the drivability and overall performance was night and day literally.

Jody

[WELTERRACER]

Just curious... What problems were you having at WOT?

Im only running 6-10lbs depending on RPM and weither or not the belt slips..LOL and really the only thing ive noticed out of the box... that the jetting is a littel Fat and it has a little bit of a surge at highway cruise (nothing i cant live with)

Im just saying it is possible to tune it yourself... Its just very time consumming!

[camcojb]

Just curious... What problems were you having at WOT?

Im only running 6-10lbs depending on RPM and weither or not the belt slips..LOL and really the only thing ive noticed out of the box... that the jetting is a littel Fat and it has a little bit of a surge at highway cruise (nothing i cant live with)

Im just saying it is possible to tune it yourself... Its just very time consumming!

Get to 10 psi and above and the problems become worse. The surging will become an annoyance and the overall drivability becomes an issue.

There is a LOT more to a carb than just jets. With a naturally aspirated engine that's often all that gets tuned, at least by do it yourselfers. But on a blow through it's a whole different level of mods to the carb, and jet changing will not get it right. You get a modded carb from someone like Scott who knows what they're doing and the $325. becomes a non-issue. The car runs that much better period. No surging at cruise, nothing. As smooth as EFI, literally.

That's the difference. You cannot get the carb as good as he can by yourself changing jets. No reflection on you, I can't either. There would be a noticable drivability difference and likely a performance difference also if you swapped to his carb.

By the way, get one of his tensioners and you no longer deal with boost between 6-10 psi! Another common shortfall of ProChargers kits. I fought that also with my first kit, almost to the point of giving up. Very frustrating.

Jody

[Sean-m]

I'm with these guys, if you can afford it, getting the carb done by a pro familiar with blow-through is worth the money. Have done carbs myself and then had a pro modded carb. My car rarely sees over 7psi and it still made a real driveability difference. .

Not to say it can't be done at home. (made 773fwhp on my mods before it really went to crap) I have one car that still runs a carb modded by me. I'd say if your starting from scratch an annular booster HP mainbody carb is a good place to start. Put the solid nitrophyil(sp) floats in it, put about an .018" high speed airbleeds in it, plug the secondary PV,put secondary jet extensions in it, do about 80F and 90R jets and see where you are. It won't have the driveability of a pro modded carb most likely.

These guys have a good bonnet http://www.superiorairflow.com/

CSU does good blow-through carb work and have a good bonnet too. http://csucarbs.com/

[HHStang]

I have a Ford 460 carbed blow-thru set up running about 15 lbs of boost. I highly recommend The Carb Shop (www.customcarbs.com) for an affordable set up. You definetly want manual secondaries and a 750 should be fine IMHO. Mine's not final tuned and ran over 800 HP on the dyno. These guys know what they are doing and their setup added over 100 HP to my home made, tuned set up. You have to get seals just right or the carb leaks everywhere, jetting can be a bear and, if you get it wrong, you create a lean condition and toast your engine. Carb Shop can also powdercoat or put finish on carb if you are so inclined. I'd also recommend Innovate's LM-1 wide band tuner. Just my 2 cents.

[TurboLark]

For the best blow thru carbs you need to go to CSU. They power many of the quickest blowthru cars out there.

[68ls1wannabe]

Look at the December 2004 issue of Super Chevy magazine. Vrbancic Brothers Racing built a 383 with a D1-SC blower that made 700 plus hp on 91 octane. They used a Carb Shop Holley 750 with 72 primaries and 84 secondary jets. I want this motor but what about a single turbo setup instead. Anybody want to comment on this idea?

[HHStang]

That's like asking Chevies or Fords. Some like turbos, some like superchargers. Both are great. Turbo has additional exhaust routing work, but both are great ways to "boost" performance.

I still like The Carb Shop's stuff the best....

[JayBird]

OK Tim, I got to see this setup when you are finished with it or even better, while you are installing.