Quick question!

[IEC Stang]

Ok so i'm kind of new to this whole forums thing but i have a question about the pi swap. If i do the pi swap, will my compression ratio be too high for a blower? Because that's what i've heard. I don't want to do the pi swap if later on down the road when i have enough money to put a blower on and i can't because of my compression. If i want to put a blower on later do i have to have forged internals? If some ppl could give some advice it would be appreciated. thanx

 

[96GT_PSL]

its very recommended that if u use a blower u forge ur internals first. either that or poor a bottle of torco into ur gas tank. it can raise ur octane rating from 93 to 100+. the higher ur octane rating the higher ur compression ratio can be.

 

[IEC Stang]

If i had my npi heads ported and polished and then my internals forged would this allow me to run even more boost because i would be keeping my compression down with having the npi heads? Could i run more boost than someone that has forged internals and did the pi swap?

 

[97stanger]

thats what i plan on doing and making 500rwhp through non pi heads. what is your goal for the car?

 

[Jrgunn5150]

As a rule, a higher compression blown motor will have more off boost "snap" than a lower compression motor. I ran mine on my headswapped car for quite awhile wiht no ill effect's. Also, LT and LS1 guy's boost on high compression all the time.

 

[IEC Stang]

My goal for the car is to get the most psi boost i possibly can and still be runnin safely, so 500-600 somethin rwh, but probably wont achieve this until i'm like 30 lol :comando:

 

[IEC Stang]

Superchargers don't like high compression but nitrous does am i right? So say someone has a 96-98 block with the pi swap forged internals, and a sc. Then another guy has a 96-98 block with npi heads that are ported and polished forged internals, and a sc. Now they both want to create as much boost as possible with the sc and still be runnin safely. Who is going to be able to run more boost before their engines can't handle anymore? That's kind of what i've been wantin to know. O0

 

[scarface]

as long as you have a good tune, and dont go crazy with the boost levels you will be fine doing the PI swap and blower.

 

[Jrgunn5150]

Superchargers don't like high compression but nitrous does am i right? So say someone has a 96-98 block with the pi swap forged internals, and a sc. Then another guy has a 96-98 block with npi heads that are ported and polished forged internals, and a sc. Now they both want to create as much boost as possible with the sc and still be runnin safely. Who is going to be able to run more boost before their engines can't handle anymore? That's kind of what i've been wantin to know. O0

Basically you have it correct, and the ported NPI guy will be able to run more boost.

 

[NERD]

It's all in the tune... 10lbs of boost is the limit w/ a vortech maybe 8 with a procharger. Use a SCT maf of something greater than the Lightning maf or you'll lean out on a cool night while not wanting to loose a race to a C5 Vette! lol. Damn, that was a bad night for a buddy of mine! Shredded the block... Either SC your NPI or start off with a PI motor would be my suggestion just to be safe.

 

[Boomer!]

Modular engines love boost and high compression, period. If you plan to continue to use the stock block you will need a good tune and lower boost levels with a P.I head. If this is not a car you drive daily running higher octane and pushing up the timing and boost will not be as big of an issue. I always say go bigor go home, stay out of the boost until you need to and you'll be fine with the compression increase.....

 

[Jrgunn5150]

Modular engines love boost and high compression, period. If you plan to continue to use the stock block you will need a good tune and lower boost levels with a P.I head. If this is not a car you drive daily running higher octane and pushing up the timing and boost will not be as big of an issue. I always say go bigor go home, stay out of the boost until you need to and you'll be fine with the compression increase.....

This is what I've always maintained. I'm still 10:1 with 10 psi.

 

[scarface]

Im glad I finally found someone else on here who thinks like me when it comes to PI swap and boost! Im all for it

 

[96 blue moon]

I am in the same situation with my car. I want to run a blower with my PI headswap but a lot of people tell me not to do it because of my 10:1 compression ratio. When I installed my stage two heads I also installed ARP headstuds and multi layer headgaskets. Can I still run a blower and have no issues if I run 8psi? This is not my daily car.

 

[Jrgunn5150]

I am in the same situation with my car. I want to run a blower with my PI headswap but a lot of people tell me not to do it because of my 10:1 compression ratio. When I installed my stage two heads I also installed ARP headstuds and multi layer headgaskets. Can I still run a blower and have no issues if I run 8psi? This is not my daily car.

Yes, and it will be better than 10 psi on stock compression, get a good tune is all.

 

[GDawg]

I'm a Blown rookie myself but I afforded one of the best. I asked someone in a specific forum about this. That person told me that if I am NPI and was going to stay NPI then get the NPI kit. But if I were NPI and went PI then I would have to get the PI kit. Cause I think in the case of KB, it's all about port matching. As far as the centri's I don't know. Talk to the manufacturer and I'll bet they could tell you.

 

[Jrgunn5150]

I'm a Blown rookie myself but I afforded one of the best. I asked someone in a specific forum about this. That person told me that if I am NPI and was going to stay NPI then get the NPI kit. But if I were NPI and went PI then I would have to get the PI kit. Cause I think in the case of KB, it's all about port matching. As far as the centri's I don't know. Talk to the manufacturer and I'll bet they could tell you.

You are refering to the port's on a Kenne Bell and matching them to the appropriate cylinder head. This is true, but it has no bearing on this thread. He want's to know if he can run boost on a high comp. motor. He can.

 

[96 blue moon]

Thanks for your input Jrgunn5150. You said that I can even run up to 10psi. with a good tune?

 

[Late4Work]

I plan on portin my npi heads so i can get a lil more boost....and its safer

 

[bigjohnson4.6gt]

would it be better to keep the pi cams or to get some blower cams? for instance im just starting the pi swap and would like to s/c it within the next 2 years and id like to get the top end done with first, i plan on having the heads ported and polished during the winter