Go Back   Third Generation F-Body Message Boards > Tech Boards > TBI
Sign in using an external account
Register Forgot Password?

TBI Throttle Body Injection discussion and questions. L03/CFI tech and other performance enhancements.

Welcome to ThirdGen.org!
Welcome to ThirdGen.org.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join the ThirdGen.org community today!


Reply
 
Thread Tools Search this Thread
Old 10-30-2007, 09:19 PM   #1
Junior Member
 
Join Date: Sep 2007
Posts: 23

Classifieds Rating: (0)
Aluminum l98 heads on a TBI 305?

Will aluminum l98 heads from an 87 Vette bolt on a bone stock 1990 TBI 305 no problem? The l98 head part number is 14101128. If yes, what head gaskets do I use to keep stock 9.3 comp ratio in my 305?

rs90 driver is offline vBGarage Page   Reply With Quote
Old 10-30-2007, 11:44 PM   #2
Supreme Member
 
Join Date: Jan 2005
Location: Hurst, Texas
Posts: 5,958
Car: 1983 G20 Chevy
Engine: 305 TPI
Transmission: 4L60
Axle/Gears: 14 bolt with 3.07 gears

Classifieds Rating: (2)
Re: Aluminum l98 heads on a TBI 305?

I would use the regular old Corvette L98 headgaskets. They are .028" compressed and will seal very well against the heads. You will not maintain your stock compression ratio, but it will be very close. The reason for this is the head gasket needs to match the chamber in the bore respect. The L98 head is designed for a 4" bore engine and needs a 4" bore head gasket. That means you will gain a few cc worth of compression space. You will be around 9.15:1 with the stock pistons.
Fast355 is offline vBGarage Page   Reply With Quote
Old 10-31-2007, 12:29 PM   #3
Supreme Member
 
robertfrank's Avatar
 
Join Date: Apr 2004
Location: Kingman,AZ (S.L.C in one year)
Posts: 2,144
Car: 1988 camaro "SS"/ 1991 Camaro Z28
Engine: 305 tbi (ZZ5.0)/ 350 TPI L9Hate
Transmission: 700r4 B&M Shift kit Edge 3200 Stall
Axle/Gears: Moser axles, 3.42 Eaton Posi

Classifieds Rating: (3)
Re: Aluminum l98 heads on a TBI 305?

what if he shaved the heads alittle? I know my ZZ4 heads have been shaved as far as they can go without hitting the intake valve seat. he should gain some compression back with that.
__________________

The ZZ5.0 is in full effect!!!
Check out my Cardomain!!! The Future Ultimate source for TBI performance.
http://www.cardomain.com/ride/3869220

robertfrank is offline vBGarage Page   Reply With Quote
Old 10-31-2007, 07:45 PM   #4
Senior Member
 
Join Date: Sep 2002
Location: CA
Posts: 325
Car: 91 Z28
Engine: LB9
Transmission: auto
Axle/Gears: 3.23

Classifieds Rating: (0)
Re: Aluminum l98 heads on a TBI 305?

Quote:
Originally Posted by rs90 driver View Post
Will aluminum l98 heads from an 87 Vette bolt on a bone stock 1990 TBI 305 no problem? The l98 head part number is 14101128. If yes, what head gaskets do I use to keep stock 9.3 comp ratio in my 305?

They will work but I believe you will need to change out your intake manifold to the older bolt pattern and run an external EGR since these heads don't have the EGR exhaust passages.
studdmstr is offline vBGarage Page   Reply With Quote
Old 11-04-2007, 09:14 PM   #5
Senior Member
 
Shadygrady's Avatar
 
Join Date: Jan 2006
Location: Flowood,MS
Posts: 1,470
Car: 87 IROC Z
Engine: 5.7 L98 TPI
Transmission: 700r4,2500 stall
Axle/Gears: G80,10 bolt 3.42's

Classifieds Rating: (3)
Re: Aluminum l98 heads on a TBI 305?

1986 and under use the same bolt pattern.1987 and up use a different bolt pattern.If it really is 87 vette heads they should fit a 90 intake.I have a 1987 intake pattern and had to moddify the two center holes a little to make the 113 zz4 heads(86 and older)to fit.
__________________
5.7,10.5:1 c.r.,ported plenum.ported/siamesed SLP runners & ported TPIS base,Bosch III 24# inj.,LT4 production cam w/1.6 R.R.
ZZ4 heads,Hooker 2460 headers,3" exhaust,
2500 stall,3.42 gear,few suspension mods.
Shadygrady is offline vBGarage Page   Reply With Quote
Old 11-05-2007, 07:37 AM   #6
Moderator
 
Join Date: Mar 2002
Location: Chasing Electrons
Posts: 11,386
Car: check
Engine: check
Transmission: check

Classifieds Rating: (1)
Re: Aluminum l98 heads on a TBI 305?

The Corvette heads/intake stayed with the older bolt pattern through '91. With a change to the LT1 for '92. The '113 heads use the older style bolt pattern. This is where all intake bolts are at the same angle.

RBob.
__________________

www.DynamicEFI.com

'92 Camaro in Dark Green Gray Metallic
RBob is offline vBGarage Page   Reply With Quote
Old 11-05-2007, 03:24 PM   #7
Senior Member
 
Join Date: Aug 2006
Location: LONG ISLAND, NY
Posts: 392
Car: 1991 camaro rs convertible
Engine: 305 TBI
Transmission: 700R4

Classifieds Rating: (2)
Re: Aluminum l98 heads on a TBI 305?

Getting of topic slightly, but i have those heads on my tbi and i noticed they didnt have the passage for the egr either, but how do u run an external EGR system?
camarorsssss is offline vBGarage Page   Reply With Quote
Old 11-05-2007, 03:24 PM
ThirdGen
1992 Camaro




Paid Advertisement


Reply

Go Back   Third Generation F-Body Message Boards > Tech Boards > TBI

Tags
14101128, 1988, 305, alluminum, aluminum, corvette, egr, external, fit, gaskets, head, heads, l98, number, part, tbi, zz4
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 


1982 Camaro '82 || 1983 Camaro '83 || 1984 Camaro '84 || 1985 Camaro '85 || 1986 Camaro '86 || 1987 Camaro '87 || 1988 Camaro '88 || 1989 Camaro '89 || 1990 Camaro '90 || 1991 Camaro '91 || 1992 Camaro '92


All times are GMT -5. The time now is 06:17 AM.


Powered by vBulletin® Version 3.7.5
Copyright ©2000 - 2012, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.5.2
All content copyright © 1997 - 2012 ThirdGen.org. All rights reserved. No part of this website may be reproduced without the expressed, documented, and written consent of ThirdGen.org's Administrators.

Emails & Contact Details