90Z-Ported plenum/I.H. hp inrease?
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Team Owner
Joined: Oct 2004
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From: altered state
St. Jude Donor '05
90Z-Ported plenum/I.H. hp inrease?
Work is going to be awfully slow til spring, so with the downtime figured I'd at least port the plenum and injector housings.
- Typically what kind of real world increases should I see?
-Is it not worth it due to the fact that there would (I imagine) be a severe port mismatch from the I.H. to the head, I mean the stock heads can only flow so much......Your expertise is appreciated
Once my other project is on the road I can do the motor completely up but as of roght now don;t have the space, just don't want to wait for more power, need a little something to tide me over.
- Typically what kind of real world increases should I see?
-Is it not worth it due to the fact that there would (I imagine) be a severe port mismatch from the I.H. to the head, I mean the stock heads can only flow so much......Your expertise is appreciated
Once my other project is on the road I can do the motor completely up but as of roght now don;t have the space, just don't want to wait for more power, need a little something to tide me over.
Last edited by cv67; Dec 17, 2005 at 01:19 AM.
Race Director
Joined: Jul 1999
Posts: 16,302
Likes: 105
From: Sun city CA
What is the going price for port and polish job on a plenum and injector housing ?
The port matching at the head would seem to nullify the positive effects somewhat in that the runner size would be reduced therefor slowing the airflow a tiny bit... Sounds like a job for mythbusters !
Would a new recalibration on the tuning be a nessasary step to maximize gains ?
The port matching at the head would seem to nullify the positive effects somewhat in that the runner size would be reduced therefor slowing the airflow a tiny bit... Sounds like a job for mythbusters !
Would a new recalibration on the tuning be a nessasary step to maximize gains ?
Last edited by Zrxmax; Dec 17, 2005 at 04:52 PM.
Drifting
Joined: Jun 2002
Posts: 1,491
Likes: 6
From: Portland Oregon
This should answer your question.
1991 ZR-1 with cat back and DRM chip before and after intake porting: Heads were not touched, No additional tuning, stock size throttle body. This was my first one, I've refined my technique since then and have made a few improvements.
1991 ZR-1 with cat back and DRM chip before and after intake porting: Heads were not touched, No additional tuning, stock size throttle body. This was my first one, I've refined my technique since then and have made a few improvements.
Last edited by locobob; Dec 17, 2005 at 01:08 PM.
Drifting
Joined: Jun 2002
Posts: 1,491
Likes: 6
From: Portland Oregon
Originally Posted by cuisinartvette
-Is it not worth it due to the fact that there would (I imagine) be a severe port mismatch from the I.H. to the head.
Pro
Joined: Sep 2004
Posts: 656
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From: Nixa Mo.
Originally Posted by cuisinartvette
Work is going to be awfully slow til spring, so with the downtime figured I'd at least port the plenum and injector housings.
- Typically what kind of real world increases should I see?
-Is it not worth it due to the fact that there would (I imagine) be a severe port mismatch from the I.H. to the head, I mean the stock heads can only flow so much......Your expertise is appreciated
Once my other project is on the road I can do the motor completely up but as of roght now don;t have the space, just don't want to wait for more power, need a little something to tide me over.
- Typically what kind of real world increases should I see?
-Is it not worth it due to the fact that there would (I imagine) be a severe port mismatch from the I.H. to the head, I mean the stock heads can only flow so much......Your expertise is appreciated
Once my other project is on the road I can do the motor completely up but as of roght now don;t have the space, just don't want to wait for more power, need a little something to tide me over.
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Melting Slicks
Joined: Jan 2002
Posts: 2,116
Likes: 84
From: Hope, New Jersey
hi
i would suggest using greg vandeventer or marc haibeck for the porting and polishing. both are excellent. i know greg is quite a bit cheaper than marc. i think i spent $1500 to have the plenum,injector housings ported and polished ,throttle body enlarged and air horn contoured . marc charges $2800 but he does all the work removing and installing.
todd
i would suggest using greg vandeventer or marc haibeck for the porting and polishing. both are excellent. i know greg is quite a bit cheaper than marc. i think i spent $1500 to have the plenum,injector housings ported and polished ,throttle body enlarged and air horn contoured . marc charges $2800 but he does all the work removing and installing.
todd
Pro
Joined: Jul 2003
Posts: 542
Likes: 0
From: MA
Originally Posted by 91vettezr1
hi
i would suggest using greg vandeventer or marc haibeck for the porting and polishing. both are excellent. i know greg is quite a bit cheaper than marc. i think i spent $1500 to have the plenum,injector housings ported and polished ,throttle body enlarged and air horn contoured . marc charges $2800 but he does all the work removing and installing.
todd
i would suggest using greg vandeventer or marc haibeck for the porting and polishing. both are excellent. i know greg is quite a bit cheaper than marc. i think i spent $1500 to have the plenum,injector housings ported and polished ,throttle body enlarged and air horn contoured . marc charges $2800 but he does all the work removing and installing.
todd
Also included with Marc is a dyno tune. That being said, I did the R&R myself and had Greg do the work. There are some others that seem to do great work also. LocoBob and Mike Ebert come to mind.
Drifting
Joined: Jun 2002
Posts: 1,491
Likes: 6
From: Portland Oregon
I've seen Greg VanDeventer's work and it's first rate, he's a heck of a nice guy too. Haven't seen Haibecks stuff up close but he seems to get very good results. The big difference in price is as mentioned above. VanDeventer just does the porting while Haibecks price includes removal/reinstall and a dyno tuned chip.
Thread Starter
Team Owner
Joined: Oct 2004
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From: altered state
St. Jude Donor '05
I know that locobob, jeff, ebert all do very nice work....Haven't decided which route I'm going to take, or if I'm taking a hammer and chisel to it myself 
.
The other two tuners are just out of range for me. What will probably happen is once the work is done, I'll get a dyno run, send the chip and sheets over to Haibeck and have him touch up the tune if it needs it as its his chip in there now. Last run w/o meth inj. was 345rwhp according to J, the former owner. Haven't had a chance to get a run in myself yet. Another 30 should be noticeable amd motivate me to pull the heads.
.The other two tuners are just out of range for me. What will probably happen is once the work is done, I'll get a dyno run, send the chip and sheets over to Haibeck and have him touch up the tune if it needs it as its his chip in there now. Last run w/o meth inj. was 345rwhp according to J, the former owner. Haven't had a chance to get a run in myself yet. Another 30 should be noticeable amd motivate me to pull the heads.
