Porting & polishing runners
Thread Starter
Drifting
Joined: Jun 2001
Posts: 1,625
Likes: 1
From: Zagreb, Croatia
Porting & polishing runners
Hello!
A few days ago i tried the car without the air filter and i could really feel the difference.
So i've decided that i will do something with filter and i will port and polish runners.
I would like if anybody have have any advices how much should i port it or is there anything else that i could do while runners and plenum are down.
1990 L-98, auto, no cats.
Sliding
A few days ago i tried the car without the air filter and i could really feel the difference.
So i've decided that i will do something with filter and i will port and polish runners.
I would like if anybody have have any advices how much should i port it or is there anything else that i could do while runners and plenum are down.
1990 L-98, auto, no cats.
Sliding
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Re: Porting & polishing runners (Sliding)
You really can't port the runners they are too thin. You can gasket match them though. Also, port the plenum and install a adjustable fuel pressure regulator. Set for your pressure prior to removal. Get the Holley, comes with all the parts. The bigger gain is in the intake base itself. Just be ready for the EGR error light to come on. The 90 and 91 are very touchy when you mess with intake or exhaust.
Le Mans Master
Joined: Feb 1999
Posts: 7,254
Likes: 0
From: Custer SD
Re: Porting & polishing runners (Sliding)
Go to my website and I have pictures of my ported upper. I'm going to get some pictures of my ported base when I get a chance. Siameesing the runner openings on the upper plenum is optional.
Le Mans Master
Joined: Jul 2001
Posts: 8,183
Likes: 3
From: Santa Maria, CA
Re: Porting & polishing runners (Romeo Barrera)
Thanks for this R.B.! I am just about to re-install my intake and wanted to clean up the internal a little. I see what you are talking about. Good job on the polishing! looks really good. Probably not major flow, but every little cfm helps. thanx!
Le Mans Master
Joined: Feb 1999
Posts: 7,254
Likes: 0
From: Custer SD
Re: Porting & polishing runners (89 Paul in cal)
Thanks, basically, I concentrated on making the sides right behind the TB openings more of a gradual opening vs. a sharp slope. You have to be careful here as you don't want to grind all the way through the side. The 90 is easier to port as it doesn't have the hump in the middle like the previous castings. The 90's EGR 'venturi' is more of a slope vs. a wall on the earlier castings. You want to radius the sharp openings to the runners. I was thinking of going as far as completely removing the casting for the bolts and then just installing studs with sealer, but it's alot of work. Like you said, every little bit helps, especially when you're trying to build a stock-looking sleeper.
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Burning Brakes
Joined: Jan 2000
Posts: 1,159
Likes: 0
From: member since Jan 2000
Re: Porting & polishing runners (vettenuts)
thanks for the tips guys.
i've got my rightside runner off and my plenum floating currently.
i'm curing an intake manifold-to-head coolant leak.
this winter i may tackle the entire top end, we'll see...
Romeo and 65Z01, i've added your sites to my faves. good info.
Romeo, nice polish job :D
i've got my rightside runner off and my plenum floating currently.
i'm curing an intake manifold-to-head coolant leak.
this winter i may tackle the entire top end, we'll see...
Romeo and 65Z01, i've added your sites to my faves. good info.
Romeo, nice polish job :D
Le Mans Master
Joined: Mar 1999
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From: Fort Worth Texas
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Cruise-In I-II-III Veteran
Re: Porting & polishing runners (Sliding)
Sliding,
If you want, I can re-program your chip to disable the egr code. Not a big deal. Go ahead and do the mods, and see if you get a code. If you do, then email me!
If you want, I can re-program your chip to disable the egr code. Not a big deal. Go ahead and do the mods, and see if you get a code. If you do, then email me!
Thread Starter
Drifting
Joined: Jun 2001
Posts: 1,625
Likes: 1
From: Zagreb, Croatia
Re: Porting & polishing runners (Marcho Polo)
O.K.
I will do it.
If the code appears i will contact you.
The problem is that i live in Croatia, Europe but if i'll a reprogramed chip we will work something out.
Thank you.
I will do it.
If the code appears i will contact you.
The problem is that i live in Croatia, Europe but if i'll a reprogramed chip we will work something out.
Thank you.