TPI heads

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Jan 1, 2004 | 12:54 PM

Firebird sweden

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From: sweden

Car: Firebid Cab-92/1989 TTA

Engine: 383 HSR TPI

Transmission: TH700r4

Axle/Gears: 4.10

TPI heads

Hi !
Does any now how much lift the stock -87 tpi heads can handle.
Thanks!

Jan 1, 2004 | 01:54 PM

The gta master

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Joined: Dec 2003

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From: England,U.K

Car: Pontiac Transam Gta

Engine: L98 350

Transmission: Th700r4

I think they can take .500 max.....
i have managed .510 on 305 L69 heads with push in studs and standard springs but the dealer i bought the cam from did not recomend this as i had push in studs and standard springs......
i did 8,000 miles + with no trouble but maybe i was lucky.....:lala:

Jan 1, 2004 | 04:02 PM

ede

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Joined: Aug 1999

Posts: 14,811

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From: Jackson County

around .475 is my limit for pull out studs or stock springs. if you're changing cams there isn't any reason not to change springs and trash the factory rotators and replace them with aftermarket retainers.

Jan 1, 2004 | 08:26 PM

88 350 tpi formula

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From: WI,USA

Car: 89 FORMULA 350, 91 Z28 Convertible

Engine: ls1, LB9

Transmission: t56, Auto

Axle/Gears: S60/ 3.73

a number of people have and do run 510 but, like already stated that is pushing it. I agree that it is pretty low lift I am using a 480/487 lift cam with push in studs on 305 tpi heads no problem so far but, I have better springs.

Jan 1, 2004 | 11:33 PM

Kevin91Z

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From: Orange, SoCal

Car: 1990 Pontiac Trans Am

Engine: 355 TPI siamesed runners

Transmission: Tremec T56

Axle/Gears: 12-Bolt 3.73

Re: TPI heads

Quote:

Originally posted by Firebird sweden
Hi !
Does any now how much lift the stock -87 tpi heads can handle.
Thanks!

Stock heads and stock springs, no more than .460" lift. If you change the springs you can go with more lift, but I dont know for sure how much.

Jan 2, 2004 | 10:55 AM

Insomniac92z28

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Joined: Nov 2003

Posts: 257

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From: Wellington, Kansas

Car: 92Z28

Engine: L98

Transmission: A4

The retainer to seal distance limits you to around .500" on the cast iron 083s. I am running .492 lift (hotcam w 1.5 rockers)with mine and didn't have to mill the guides down, but it was close. I would recommend going to a lighter retainer and get new springs for any cam swap. I am running comp 981s(Scoggin Dickey $55) and LT1 retainers(Ebay $13.50 shipped w/locks).
Good luck,
Charlie