C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

'91 L98 Head Porting

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Old Nov 12, 2018 | 12:24 PM
  #21  
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So here is my plans for the engine:
*-Port heads
*-2.00/1.570 LS 8mm
*-KMotion LS drop in kit
*-1.60 stainless steel rockers
*-Erson 226/234 cam w/.545 lift
*-Port upper and lower manifold, weld OEM lower
+-TPiS big runners
*-52mm throttle body
*-Headers
*-2xxx stall converter
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Old Nov 12, 2018 | 08:26 PM
  #22  
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Drop in kit is springs/retainers?
Like the small stem conversion, who can the guides be purchased through (2.02/1.6 for Dart)
Those heads and seats are horrible from the factory!
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Old Nov 12, 2018 | 08:47 PM
  #23  
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Originally Posted by cuisinartvette
Drop in kit is springs/retainers?
Like the small stem conversion, who can the guides be purchased through (2.02/1.6 for Dart)
Those heads and seats are horrible from the factory!
PEP has any guide you need, but these I'm going to use a 8mm guide liner

Picture of the KMotion kit.


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Old Nov 13, 2018 | 11:30 AM
  #24  
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Related:

Lot of good information and some dyno match ups for various TPI components here:

Just a lot of good, general background links and information too. It's a good read.



http://garage.grumpysperformance.com...ith-tpi.10494/

Last edited by confab; Nov 13, 2018 at 11:31 AM.
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Old Nov 13, 2018 | 06:34 PM
  #25  
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I decided for what I want to do, the OEM manifold even with big tube runners, was going to be too much work.

Decided on a TPiS manifold.
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Old Nov 14, 2018 | 11:08 AM
  #26  
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Polished stainless rocker I'm using. Very nice quality vs price.


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Old Nov 15, 2018 | 04:04 PM
  #27  
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Factory steel guides cut down to .500 OD and .315 guide liners installed.


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Old Nov 15, 2018 | 04:05 PM
  #28  
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Multi-angle intake valve job and radius exhaust.


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Old Nov 16, 2018 | 08:21 PM
  #29  
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Heads are done. Flow data on 4.00 fixture. .100-.800 and no exhaust pipe.




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Old Nov 16, 2018 | 08:56 PM
  #30  
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Absolutely beautiful.. What tools are you using?
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Old Nov 19, 2018 | 06:23 PM
  #31  
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Heads fitted with LS hardware.
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Old Nov 20, 2018 | 05:03 PM
  #32  
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Old Nov 20, 2018 | 05:55 PM
  #33  
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Very nice.. What tools are you using to finish that? Carbide cutters and sanding rolls?

I've got a plenum and some runner that I'm going to port match and smooth out, and I want it to look exactly like yours when it is done.
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Old Nov 20, 2018 | 05:59 PM
  #34  
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I use a SE5 aluma burr on everything.
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Old Nov 20, 2018 | 07:08 PM
  #35  
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Some damn good numbers. How is the velocity on those ports if you mind my asking?
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Old Nov 20, 2018 | 09:49 PM
  #36  
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It's almost a shame to cover up something that pretty..
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Old Nov 21, 2018 | 04:27 PM
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To '91 L98 Head Porting

Old Nov 21, 2018 | 11:30 PM
  #38  
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Awesome.. It's beautiful.

You ever consider becoming a forum sponsor?

Lot of guys would pay for work like that..
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Old Nov 23, 2018 | 07:37 AM
  #39  
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Very nice job, they look and flow great.
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Old Nov 23, 2018 | 08:20 PM
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I see a man sharing his passion. Mr. Speiers has all the work he can handle. Thank you.

Last edited by hogandtow; Nov 23, 2018 at 08:22 PM. Reason: Spelling
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