Turbo size for 383
Turbo size for 383 so i was going to run a forged 347 using a stock crank i picked up but realized after i get it cleaned, cryoed, and balanced on a rotating assembly im probably going to spend more then if i just got the rotating assembly complete and already balanced from a vendor. so question is, is my PT7675 i just bought too small for a 383 or would something like a pt80 or maybe a BW s480 work better. thanks.
Will an S480 work better? Yes.
Will the 7675 work? Yes.
Id say if you have the room go for the S480 but keep in mind its quite a bit larger than the 7675. It really depends on what your goals are though. My car is full weight with a dinky .81 hotside and it traps 105 mph in the 1/8th on 12lbs with a junk intake and cam so it all comes down to how much power do you want. Im sure if I turned mine up to 17-18psi it would have to be close to 110 mph so ya gotta figure 135-140 ish in the 1/4 which is enough for me but if you wanna go insanely fast get the s480.
Will the 7675 work? Yes.
Id say if you have the room go for the S480 but keep in mind its quite a bit larger than the 7675. It really depends on what your goals are though. My car is full weight with a dinky .81 hotside and it traps 105 mph in the 1/8th on 12lbs with a junk intake and cam so it all comes down to how much power do you want. Im sure if I turned mine up to 17-18psi it would have to be close to 110 mph so ya gotta figure 135-140 ish in the 1/4 which is enough for me but if you wanna go insanely fast get the s480.
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From: Okmulgee, OK
The PT7675 isn't too small per say, it will work just fine. You may run into some back pressure issues up top though. The S480 would be a great choice, but it is a very large (physically) turbo.
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I personally wouldnt put a 7675 on a 383 inch motor. thats not enough turbine to support those cubic inches at much more than 6000 rpm imo. The camshaft would have to be crutched to try and extend the rpm range and get it to make power up top. It would require a reverse split cam.
I'm running a PT7675 Billet wheeled turbo on a 383. Makes mid 600s on about 9.5 psi or so. Boost comes in pretty quick and keeps pulling pretty hard all the way to redline. My cam is a 224/224 114.
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From: Joliet,IL and Las Vegas 50/50
Kinda depends on how far you want to push it. If only going to run pump gas 93 octane at a modest boost pressure then just keep the pt7675. If you want to max effort the thing then consider the BW. Honestly I love the pt7675 and wouldn't go with a BW primarily because I couldn't fit the BW without redoing alot up front.
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thanks guys. im really only look for a max of about 850hp, mostly running lower boost to keep it around 600-650. I jumped on the Huron Speed group buy for the V2 kit and they say the s480 will fit so i dont think fitment is an issue. any thoughts on the pt80 or 88?
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From: Okmulgee, OK
http://www.liljohnsmotorsports.com/b...m-turbine.html
I went with PT88 .96 T4 for my 383ci I'm installing everything next week on my manaul C5Z06
Hoping for low 800rwhp on 14-16psi and close to 1000rwhp 20psi on C16 Fuel.
I'd be happy if it spooled at 3500rpm and pulled to 6800rpm.
Hoping for low 800rwhp on 14-16psi and close to 1000rwhp 20psi on C16 Fuel.
I'd be happy if it spooled at 3500rpm and pulled to 6800rpm.
Thanks buddy. 
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Those 224/224 cams you see in the blower world are almost a miller cycle cam with dynamic compression reduction from what Ive read elsewhere, and a 383 with boost down low is my goals actually, tho if anything happens to my block Ill probably go for a 408 instead.
im looking for a *tiny* set of twins thatll spool down low with reletively high static compression, compensated for by dynamic compression reduction through a late intake closing, right?
your setup sounds real close to that and youre the first guy Ive seen with anything like this.
[edit] yes I know Im king necromancer around here, yellow bullet, and the tahoe forums. thats what searching gets you lololol 🤣