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TPI... runners/base versus stealth ram?

KANE

Moderator
Joined
Mar 2, 2002
Messages
3,244
Location
KY
Corvette
Dark Blue 1982 Trans Am(s): Polo Green 1995 MN6
Thank you to all the C4 TPI guys. Ya'll have been a world of help. I could NEVER have done my C3 TPI project 5 years ago without guys like you!

So, seeing as I have the 91 GM TPI style system, I am going to ask some opinions about some TPI mods.....

For starters.. here is what I have-
The TPI is based upon a GM 91 speed density system. It utilizes an 85 Vette manifold; 89 Vette runners, upper plenum, throttle body and a large style distributor with accel super coil. Very GM and very stock. My system runs without emmissions equipment (no AIR sys. or EGR). Its set up for closed loop operation and Street Chip from TPIS. I have LT4 injectors on the factory fuel rail although its been converted to -6 AN fittings with a stock style pressure regulator.

The engine itself is a 350 Goodwrench motor-
Compression Ratio: 8.50 to 1
Crankshaft: Cast Nodular 3.480” Stroke
Heads: Cast Iron, 72cc
Valves: 1.940” / 1.600”
Camshaft lift: 0.390” / 0.410” Hydraulic
Duration @ 0.050”: 195° / 202°
with Ram Horns and sidepipes

I have a 700R4 tied to a 3.08 rear end. Weight with 1/2 tank of gas is 3300lbs. No kidding.


So here are the a few options for what's next:

Mini-ram-
Its pricey, like elitist pricey. Is it worth it?

Vortec heads-
Nice price, but if I am replacing the manifold I may just as well upgrade to something better.

3.73 gears. Enough said.

Cam-
Crane Compu-Cam may be fun too. The best for the money?

Personally, I think my Dream combination would be a 52mm TB, runners, cam, heads and gears.

I would like to hear some TPI mod stories from ya'll.

Thanks!!!
 

grumpyvette

Well-known member
Joined
Apr 17, 2001
Messages
841
Location
Loxahatchee, FL, Palm Beach co
you need to decide on your goals and budget BEFORE you start, and how streetable the car will be AFTER the mods.

warm street
http://www.sdpc2000.com/htm/vortec_tpi.html (extensively ported with ported runners and plenum)
the TPI and your present gearing would work well with a vortec base and CALL crane or CROWER for cam advice

hot street
youll need a super ram, stealth ram, or mini ram, (which depends on the cam duration, compression ratio,and which aftermarket heads and rear gear you choose)
but the COMBO must match in both airflow and rpm range

DECIDE FIRST on what YOUR REALISTIC GOALS AND BUDGET ARE!
a 11 second street car is going to cost big dollars if you expect it to run correctly
 

Ken

Gone but not forgotten
Joined
Jan 30, 2001
Messages
8,236
Location
Hermosa Beach, CA
Corvette
1987 Z51 Silver Coupe
grumpyvette said:
...an 11 second street car is going to cost big dollars if you expect it to run correctly

I agree. I'm still spending money, but then it never ends for me. ;)
 

vader86

Well-known member
Joined
Sep 5, 2001
Messages
807
Location
Baton Rouge/LSU
Corvette
1986 White Coupe w all options.
With the Superram you could keep the current rear gear and 700r4, although it would be better to beef that up no matter which route you choose.

I would go with the 113 vette heads or the AFR 190 heads, best youre gonna get.

SR and 219 cam, headers; with computer tuning, should be deep in the 12s.
 

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