[thatdavidkid]

10.8 is believable considering the combustion chambers on npi heads are larger than pi heads... however, if you have a pi swap ( i saw something about a pi intake... i wasn't aware of one but is there a pi intake kit for npi heads???) then your compression would be much higher than 10.8:1... anywho... i say get your car to someone who can tune it and work on it asap... probably a smaller crank pulley and/or a larger blower pulley are in order... then have it tuned, add that boost a pump and injectors, and you'll be changing a number in your "can i hit ***hp" threads...

[pimpdout98gt]

first off i appreciate all of you guys' input. i'm not really sure what my compression ratio is but i know i get detonation when i pull up to higher rpm's with a 2.75" supercharger pulley and stock crank pulley and that never happened before i changed my pistons. i've purchased a whole laundry list of parts since i'm out here in the desert. i thought about installing my overdrive crank pulley and running high octane fuel but since it's a daily driver i would be just wasting money. since a rebuild or a 4 valve motor swap are out of the question for me, i guess i will just install the original supercharger pulley since i can't bring myself to remove my Novi and get a professional tune. does anyone know what my compression could be? i do have MLS head gaskets and ARP head studs. if i install my original supercharger pulley but add a AFM powerpipe will that still be too much boost? i guess i need to stop focusing on maximum boost and power and start thinking about safe tune and engine preservation.

[FineLineMtrSprts]

Well first off..again...your engine combo is all WRONG for boost unless its an all out race motor. Anything over 10 to 1 is just asking for trouble..if your compression IS above that,that is reason for your detonation. The reason it didnt happen before you installed those pistons is probably because it was lower with the other pistons. If you want to run boost at that compression level you need to back it down AND get a dyno...which you need either way. Even with the original pulley i doubt it will run like it shuld without a dyno tune.The arp studs have nothing to do with compression and your headgasket MIGHT be worj +/- half a point of compression. Which if you are around 10.5-10.8 to 1...STILL put you too high.What do "I" think you should do.....if you have to drive it put the biggest blower pulley you have on and whatever tune you do have and baby the car around and save up for another rebuild wish dished pistons and a professional dyno tune....or if you have a beater let the car sit and save up for the correct parts.

[pimpdout98gt]

yeah i really didn't research my engine internals when i set out to get parts to get my engine built. my whole intention from the beginning was to be forced induced. i knew flat top pistons would give me more compression but not as much as i ended up getting. i wanted a strong powerful setup and i got it but it's to dangerous. i know it will be a little better running the stock pulley with a powerpipe but i think i still will be pushing it also. would running race gas improve my setup by allowing the extra boost to get used as power efficiently? because i wouldn't mind turning my car into a race gas monster. i would just have to find a local race gas supplier and get my car tuned only for race gas. with my compression and the amount of boost i am currently running, how much timing will they have to remove for my car to be safe on 93 octane? what i am getting from all of you guys' responses is that my car cannot be tuned the way it is? if i ran 15-20 plus p.s.i. with my compression ratio couldn't the tuner just remove the necessary timing to get my car safe and running? or will he have to remove to much that my car will not have any power?

[FineLineMtrSprts]

YOu would have to remove to much timing and still run race gas...you willing to spend 6-7 bucks A GALLON on gas? Even then it still wont be a worthy package. Theres a reason you never see many race bred engines that run high compression and lots of boost..its just not safe and wont last.

[acidtonic]

Originally Posted by pimpdout98gt yeah i really didn't research my engine internals when i set out to get parts to get my engine built. my whole intention from the beginning was to be forced induced. i knew flat top pistons would give me more compression but not as much as i ended up getting. i wanted a strong powerful setup and i got it but it's to dangerous. i know it will be a little better running the stock pulley with a powerpipe but i think i still will be pushing it also. would running race gas improve my setup by allowing the extra boost to get used as power efficiently? because i wouldn't mind turning my car into a race gas monster. i would just have to find a local race gas supplier and get my car tuned only for race gas. with my compression and the amount of boost i am currently running, how much timing will they have to remove for my car to be safe on 93 octane? what i am getting from all of you guys' responses is that my car cannot be tuned the way it is? if i ran 15-20 plus p.s.i. with my compression ratio couldn't the tuner just remove the necessary timing to get my car safe and running? or will he have to remove to much that my car will not have any power?

Have you thought about removing the blower and going NA? You already have a hell of a start for a NA application. You wont have as much power but it might be the cheaper solution since you already have the build. Next up would be head work and valvetrain plus NA cams and proper runner length intake.

[ujslost]

how about some methanol injection or an after cooler?

[pimpdout98gt]

yes i have thought real hard and am currently still thinking about removing my supercharger but that would defeat the purpose of me purchasing this $3,600 supercharger system. i really don't want too put any more money into my car. i do have a nice start for a n/a build but i don't want to spend any more money for things like headwork, etc. i do have cams and a p.i. intake but i don't know if these things would get me the most power on a n/a setup. i would probaby have to get a stage 2 or 3 cams with a high flow intake like the svo or bulitt. as far as meth injection or an after cooler i have pondered those things around in my head a bit. i simply don't trust the meth injection even though it looks like a promising addition. what happens when your injection pump fails or you lose fluid. i do have a paxton intercooler. i'm sure it helps out a bit with the charge temp but not as good as i need it. and an after cooler works good at the track when you put ice in the resovoir but what about as a daily driver, when your toting around town and it's the summer heat. i'm pretty much just gonna have to reinstall the stock supercharger pulley which i think is about 3.5" and leave my factory crank pulley on. with a Novi 2000 and a powerpipe i still should produce almost 12 p.s.i. of boost. i'm gonna convert back to draw through with the SCT big air and 60's. i will find a good tuner. i have 2 tuners nearby. Delk which tunes with diablosport or Dyno Speed in memphis which uses SCT software. i prefer SCT but i will use whatever is available. thanks guys

[HBK_2007]

MAFIA MOTORSPORTS RACING.....THE "ANTI-RICE".....

read that then think about a N/A set up

[97S281]

Sell the supercharger and use the money to get your new heads, cams, intake and valvetrain. Talk to a reputable builder with modular engine experience BEFORE you purchase any new parts. Get what you need to get the most from your shortblock as is.

That way it's not costing you much coin from your pocket and you get a very fast n/a motor that will actually last a while.

[pimpdout98gt]

i think my combo is still streetable. i realize that i may have more compression with my setup than i need but that can be worked around. i'm 35 years old and in the Army so i don't have time to be working on a n/a combo like that. i'm gonna work with what i got because i will probably end up selling my car in a few years anyway. Thanks guys

[G.T. Rags]

Originally Posted by pimpdout98gt i think my combo is still streetable. i realize that i may have more compression with my setup than i need but that can be worked around. i'm 35 years old and in the Army so i don't have time to be working on a n/a combo like that. i'm gonna work with what i got because i will probably end up selling my car in a few years anyway. Thanks guys

goodl luck

[Trick Tuners]

You could hit 500 with that combo using some race gas. high compression and high boost will require 100+ octane, but will make insane power. How hot are the IATs? You may be able to make more power with more timing and less boost depending on how hot everything is. If your IAT's are 150+ you can really benefit from methanol injection.

[pimpdout98gt]

well i've been deployed for the last 10 months so, i really don't remember what my IAT's were before i left but i do remember that they were very cool. my IAT's have never been hot. i use to datalog almost every day when i was at home. the Novi 2000 is a very efficient blower so it never really created a problem as far as my IAT's. it's the combination of higher compression and wanting high boost. when it's all said and done the Novi will be the last man standing. this Novi is my second supercharger. before it i had a powerdyne. it was junk and i had to change bearings in it all the time. if i knew of a gas station nearby in my home town that supplied 100+ octane i wouldn't have to worry. i would pay the price for the gas but i would dirve my car less often like i do anyway. i really haven't even broke my engine in and it was rebuilt over a year ago. i'll admit when i got my car dynoed i had my sniper tune in. i dynoed my car one week and there was a problem with my air/fuel ratio. i took it home that night, got on sniper forums, asked a few questions and the problem was solved. next time i went to the dyno it was my timing. the tech said it was as high as 23-30 degrees and max rpm, which was too high. i brought my interface and laptop along also. i tried to pull timing out but to no avail. the tech tried also even though they specialize in diablosport. he failed also. he tried changing tune specs like changing octane rating, adding boost numbers. anything to trick my computer to bring down timing. nothing worked. i have too much compression, too much boost and too much timing. that could have been my only problem. that i have too much timing in my combo and was not able to bring it donw due to inexperience with the sniper software. i'm gonna ive the sniper stuff one more try and bring down timing. i think that might have been the reason why my car is detonating. i do have an intercooler and the detonation only occured during top speed/rpm runs trying to determine what my boost was. methanol injection is just another $500 that i'm not willing to put out right now.

[Trick Tuners]

Originally Posted by pimpdout98gt the tech said it was as high as 23-30 degrees and max rpm, which was too high. i have too much compression, too much boost and too much timing. that could have been my only problem.

wow! Its amazing that the motor is not already cooked with that amount of timing, boost and compression! I would seriously consider backing the boost down a lot due to the compression, if you need to run on pump gas. Also remember that probably 90% of the guys that blow their motors are doing high speed runs. Tuning for a dyno pull is much different that tuning for the standing mile and extended boost.