Ive been doing major researh the past few nights to prepare for my blower adventure. I think that since Ill be purchasing another newer/stronger rotating assembly that I might was well make it a stroker also. I really want to do this to help out the "no boost" low end Im gonna have to deal with. My block is already at the machine shop...and they said they would find me a forged rotating assembly(they mentioned SCAT and Eagle, hbeams and blower pistons, trying to find 8.5:1 or so...but I dont think its going to happen unless I dont do a stroker) thatll handle my 800hp goals. I told them I would as around on the boards and see if you guys had any good recommendations to go with.

Main problem seems to be finding a piston thatll allow low enough compression to run at least 10psi or more of boost(depending on how my enigne responds to my ported LT1 heads could be more or less). Im guessing we might have to get custom pistons if there are not any off the shelf ones available. I would appreciate any recommendations and part numbers for them. It would be for .030 over and 5.7" rods.

 

JE offers a piston with a -31cc dish, but you will still need a set of heads that has a larger combustion chamber in order to get to the 8.5:1. Most people recommend getting AFR heads because you can get combustion chambers up to 74 or 76 cc which will allow the lower compression ratio.

P.S. I am researching the same thing.

Check out Combination Motorsports as they have these pistions listed there.

 

I went with custom CP pistons in mine. I only went .010" over and was able to get the 8.5 to 1 compression I wanted with stock heads. Very nice pistons but they aren't cheap.

 

The JE -31cc blower piston is excellent.

Rich Krause

 

I want to use my stock heads also. Funds are getting too low(and I still have to buy the blower) to afford another head swap/job. My heads do have stock size valves but with the kick *** valve job and backcut/undercut valves...they flow better than even most of the large valve/larger cc heads till about .200", they they flow like normal good ported LT1 heads. So, I think theyll be alright since theyll be under boost for the top rpm range anyhow.

I think we might go with a custom JE if I do the stroker. Its becoming so much of a PITA...Im about to just leave it a 355. I have a feeling making is a stroker is going to cause me more problems then good. Im going to call the machine shop and see what they have found and tell them your suggestion(-31 JE). Whats the highest compression ratio I could get away with and still effectivly run at least 10psi( and as much as 20psi or more....hopefully as much as they s/c will provide) on a stroker ? Is that even possible, or should I just stay 355 with lots of boost and sacrifice the low end!?!? These decisions are such a PITA. Thanks.

 

Is it used? What rods/pistons/crank/bearings? Does it have 4bolt center mains(any strap on the front main?)? I have already invested so much into the 4bolt conversion/overbore/mangaflux/etc...that I would really hate to not use my block. Im probably not interested cause shipping these damn things will cose me half as much as it will to complete what I have started. Let me know what you have anyhow and a price.

 

Well - all I can tell you is to hold on tight...... I just Barely got done w/ mine and I spent over 4000.00 more than I expected.... It is going to happen - When you gog 383 with a stroker and a blower - you have to change everything - and I mean everything!!!! exhaust, intake custom stuff - and not to mention all the stock stuff that you will replace once the old one is out....

But back to the subject.....

I used j&e - they worked awesome.... My advise to you is - if you are going with stock heads, have a professional - I mean professional do them - up the cc size and dont scrap it together. U are investing too much money in it to half-*** it.

Just my .02 cents


Paul

 

heads have 60cc chambers, and I'm using a 28 cc dished JE piston

 

Thanks for the warning...but, you are not telling me anything I dont know already. I have alredy spent over 8k on the N/A setup that I initially planned on running. I am now swapping the complete rotating assembly, block work(plus the 4bolts studded mains/and strap over front main), etc. I sepent almost $1400 to have my stock heads ported by the best that I knew of(and no, its no names from these boards)...and it shows too. My heads outflow more than half of the LT1 heads on this site in high lifthttp://www.malcams.com/legacy/misc/headflow.html and destroys all but the 32valve and a hogged out LT4 in lowlift numbers(thats because my valve job was $400 of it and probably the best you can get(guy also does NASCAR engines). Ill go dig out the spec sheet on the heads and see what the final size of the combustion chamber, but I think it was around 58cc . Ill also be installing 6pt roll cage, dual intank pumps, low independence convertor for larger fuel injectors, tubular PA kmember, bigger TB, etc....bsically, Im prepared for it all. I just need to find the perfect setup to put into action.

If I go stroker, then Ill probably use the -31cc JE and work with what itll give me. Ill be running a intercooler/aftercooler and it wont be some stock POS either that comes with most kits...So thatll help me out some. Im going to call the machine shop and see if they found anything better. I could always stay 355....but it just wouldnt be the same. I would love to be able to say that my car is: Injected, Stroked and Blown! Im going to make it happen, its just a matter of selecting the right parts to work together.

Also, which s/c do you recommend? I was thinking of D1SC(due to no oil lines and 1400cfm, 4.10:1drive gears), but RacinLT1 mentioned the F1 or F1 C/or R or F2M. Is anybody running this one and if so, whats your opinion on it? Is self oiling also which I really like and it can make monster 1500+cfm and it had something like 5.0:1 drive gears). Now, Im thining that if that 5.0:1 gear size was on the D1SC it would cause it to make boost fairly early compared to its stock gears(and run more boost obviously). However, with this gear coming on a bigger blower....does that mean that the boost will essentially come in close to the same time as a smaller blower with smaller gear and just make a **** load more up top? Or, will it still come in sooner and with more boost/cfm to compliment it?

 

Believe me - it's alot of work, money and wasted time... But It is worth it in the end.

I went with the t-trim vortech - yea the oil lines were a pain in the ***, but well worth it in my opinion. If you do it right - it won't leak and you don't have to worry about oil levels and changes...

 

N2OpwrdTA, Just wondering when you had all that work done on your heads, How come your combustion chambers are still at 58cc. I had my stock LT1 heads opened up to 68cc , Would have been 71cc but had to surface the heads and went with a JE -16cc dished piston for a 9.5 CR. Just curious,what are your flow #'s

 

You might try looking into the probe PRS kit. Not many guys know them here but they do a ton of mustang stuff, and offer a nice chevy 383 kit. They asked me what compression i wanted, What size valves, how much lift, and size of cylinder heads, and sent me custom Ross pistons. I'm pretty happy with the stuff, but at the same time it's not running yet so... I think there web page is www.probeindustries.com Any ways good luck.

Paul

Oy yeah the kit i got was for the older SBC blocks. (but i believe everything is the same except for the rear mani seal thing.)

 

Alright guys...I went and had the combstion chambers cc measured so I would know for sure. My heads were milled .005 due to scratches and even with that they are all at about 60cc. Head flow numbers are a real PITA to type out, but they flow really well espically down low for ported stockers(come fall or so, Ill upgrade to AFRs or something with larger chambers so I can run even more boost). My heads intake are .050" 42.5, .100" 75.4 .200" 136.8 .300" 199" .400" 238.5 .500" 254 .600" 264 Exhaust numbers are good also and max out at 198@.600"

Anyway...I decided on a setup and ordered it yesterday. It an eagle 4340 crank and Hbeam 5.7" rods(with L19 bolts for up to 1000hp, good insurance IMO since thats what tends to break on a rod before most other possibilites), JE -31cc pistons, Clevite H series bearings and Hellfire rings all internally balanced for a little over $1700. The shop is giving me a small discount since I have been struggling with this project for sol long with them.

I should have it in 10 days. Thanks for the help guys.

Oh yeah...I looked into those Probe Ind. pistons a while ago, I found them on my own. But, thanks for the lead anyhow.

 

I'm using exactly the same combo in my 383 eagle je and the hellfire rings much less blowby than the je standards I ran the first 6000 km. Better leakdown too.

John Carpico