D1SC 12 rib going on a stock LT1

[KLaBZ28]

Well I decided to bail out on my nitrous kit after I found a killer deal on a complete D1SC procharger setup. It came with the upgraded bypass valve, fmic setup, 3.40" and 4.25" head unit pulleys, 3 belts and what looks like to be a 7.65" crank pulley (haven't measured it yet) with the crank pulley spacer. Its complete with all hardware, brackets etc. I did some math and it looks like using the 4.25" pulley should net me 9.5 psi. Is this right or does this setup make 8psi?

Currently I have an ASP under drive pulley. Is there a recommended pulley to use in combination of this setup? Other than that, I think I'm pretty much good. I want to get it running on the 24x pcm to prevent predetonation because I know that would kill the bottom end at 8 psi - might even do meth injection down the road. My biggest hang up right now is I cant decide between throwing the complete T56 swap I have sitting around in or go with a 4L80e conversion. This will help me decide what cam to go with. Looking for any advice here as it is my first time messing with boost. I know it sounds crazy boosting a stock engine but I have a couple low mile bottom ends sitting around and I'm not looking to make crazy power. Think 450+ at the wheels will be just fine for me

[shownomercy]

8psi and a SBE?

I predict some broken ring lands in your future.

[gmpowered]

Kudos for recognizing that the stock ignition and pcm are not up to the task.
I believe the 24x will improve longevity on a stock short block. Misfires due to low spark cause knock aka the craptispark. That and having to cobb job a tune to make it run.
I have personally wanted to test this theory. Funds and other priority's...

IMO you dont know how much boost it will make until the blower its on the car. You can ballpark it though. Either way tuning it would be rich with low timing.

Looking back, or having a second car to try it on I would,
Run 58x crank reluctor and run a 6l80. Driveshaft cross-member verter and trans to engine mount would need a change. But if building from scratch not a big deal.

[MoeHorsePower]

[QUOTE=KLaBZ28;458764] I want to get it running on the 24x pcm to prevent predetonation because I know that would kill the bottom end at 8 psi -

So with the 24x system you cannot get detonation, is this what you are saying?

[QUOTE=gmpowered;458766]Kudos for recognizing that the stock ignition and pcm are not up to the task.
I believe the 24x will improve longevity on a stock short block. Misfires due to low spark cause knock aka the craptispark. That and having to

Stock ignition would be pushed to its limits, but the stock pcm is not up to task?? I have been running boost since 97 on a STOCK pcm, past supercharged with 648 rwhp and now turbo with 710 rwhp, if you know what you are doing in the tuning dept, it can be done...

[KLaBZ28]

I want to get it running on the 24x pcm to prevent predetonation because I know that would kill the bottom end at 8 psi -

So with the 24x system you cannot get detonation, is this what you are saying?

Kudos for recognizing that the stock ignition and pcm are not up to the task.
I believe the 24x will improve longevity on a stock short block. Misfires due to low spark cause knock aka the craptispark. That and having to

Stock ignition would be pushed to its limits, but the stock pcm is not up to task?? I have been running boost since 97 on a STOCK pcm, past supercharged with 648 rwhp and now turbo with 710 rwhp, if you know what you are doing in the tuning dept, it can be done...

Agreed, and I'm not knocking on the LT1's system or people who use it. For my application where slight predetonation will blow my stock pistons apart I think it will be better to have a more consistent ignition system. I've been running the opti for years with no problems and ignoring the suggestions by friends to run 24x because I just don't see the point. Boosting a stock LT1, yeah now 24x sounds like a good idea to me.. I have no doubt I could tune the car for this setup with the opti but I would just be worried about a misfire or something to go wrong.

Predet is a lot less critical when you have forged pistons.

[gmpowered]

[QUOTE=MoeHorsePower;458799][QUOTE=KLaBZ28;458764] I want to get it running on the 24x pcm to prevent predetonation because I know that would kill the bottom end at 8 psi -

So with the 24x system you cannot get detonation, is this what you are saying?

Kudos for recognizing that the stock ignition and pcm are not up to the task.
I believe the 24x will improve longevity on a stock short block. Misfires due to low spark cause knock aka the craptispark. That and having to

Stock ignition would be pushed to its limits, but the stock pcm is not up to task?? I have been running boost since 97 on a STOCK pcm, past supercharged with 648 rwhp and now turbo with 710 rwhp, if you know what you are doing in the tuning dept, it can be done...

Not saying it cant be done..Im sure someone like you could run 2000 hp on a stock pcm if hp numbers matter.
Stock opti no bandainds? no coil on plug... Stock pcm...what else did you need to modify to finagle it to work... a boost a pump...new press reg ect ect. Then finding a tuner or a dyno shop who will tune and dyno it....good luck.

people saying they run an opti but have delteq....people say they run a stock pcm...buy have boost a pumps to control fuel.....

[dawdaw]

[QUOTE=gmpowered;458814][QUOTE=MoeHorsePower;458799]

I want to get it running on the 24x pcm to prevent predetonation because I know that would kill the bottom end at 8 psi -

So with the 24x system you cannot get detonation, is this what you are saying?


Not saying it cant be done..Im sure someone like you could run 2000 hp on a stock pcm if hp numbers matter.
Stock opti no bandainds? no coil on plug... Stock pcm...what else did you need to modify to finagle it to work... a boost a pump...new press reg ect ect. Then finding a tuner or a dyno shop who will tune and dyno it....good luck.

people saying they run an opti but have delteq....people say they run a stock pcm...buy have boost a pumps to control fuel.....

Wtf do boost a pumps have to do with controlling fuel lol! Pulse width and fp determine how much fuel ultimately gets into the cylinder.

Boost a pumps are band aids for weak pumps that can't suppply enough fuel and the owners to cheap to put a real pump in the car

[shownomercy]

[QUOTE=dawdaw;458820][QUOTE=gmpowered;458814]

Wtf do boost a pumps have to do with controlling fuel lol! Pulse width and fp determine how much fuel ultimately gets into the cylinder.

Boost a pumps are band aids for weak pumps that can't suppply enough fuel and the owners to cheap to put a real pump in the car

Not always true, I would love to run a surge tank setup vs the big ass magnafuel I have now.

[blackbirdws6]

I would absolutely confirm the pulley sizing for obvious reasons. I would recommend meth only to help keep things cool.

[KLaBZ28]

yeah meth is definitely happening, to prevent shownomercys predictions haha. The head unit pulleys are confirmed at 4.25" and 3.40". Its the crank pulley I haven't measured yet..