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-   Performance, Brainstorming & Tuning (https://www.gmforum.com/performance-brainstorming-tuning-96/)
-   -   Porting. (https://www.gmforum.com/performance-brainstorming-tuning-96/porting-224287/)

LakevilleSSEi 10-30-2005 01:30 PM

Porting.
 
What kinda porting could I take care of while my LIM and S/C is off right now?
Any type of noticable gains anywhere from doing that? Would it be worth the time?

big_news_1 10-30-2005 02:03 PM

Well, an obvious thing would be to gasket-match the LIM. Set your old gaskets on there and have at it with a grinding bit and a rotary tool. I'm not sure how much there is to be gained, but I don't think it could hurt anything.

As far as your blower is concerned, I have no idea what you could port or polish. Maybe Bill will weigh in here.

LakevilleSSEi 10-30-2005 02:07 PM

See IIRC, polishing doesn't work on our cars too well because the air becomes too straight. It needs the texture in the runners, or it ran better with the texture in there. Something like that.

But if there's gonna bee some good gains to be had, then I'm all about it. Because I don't know when I'll be that far down inside that engine again.

willwren 10-30-2005 03:23 PM

The LIM outlets are 20% smaller than the head inlet ports on the Series 1. Measure and port-match. Matching to the gasket won't be necessary, unless you're also porting the heads.

You'll have to disassemble the SC to MILDLY port the outlet. Do not increase the outlet size, just break the rough edges. My porting is posted in Forced Induction.

LakevilleSSEi 10-30-2005 03:27 PM

Did you have measurements for the LIM and head ports in that post?

Did you pick up any gain? 20% sounds like quite a bit.

willwren 10-30-2005 03:37 PM


Originally Posted by LakevilleSSEi
Did you have measurements for the LIM and head ports in that post?

Did you pick up any gain? 20% sounds like quite a bit.

Measurements on my car are posted. The combination of that porting and the massively ported TB are causing a lean condition despite the flowmatched injectors and walbro fuel pump, although it's not as bad as it was. My gut tells me the LIM porting is not the problem, but I'm simply flowing more than the MAF can handle. When I'm running enriched early in the morning, it has insane amounts of power compared to before. It would easlily spank my 95 in these conditions.

So the jury is still out on the LIM porting, and you'll be taking the same risk as me without my final green light on it. In theory, it should help move the boost/fuel into the cylinders more efficiently. But you may also have to port your EM's to make up for it, or you're almost certainly going to have KR. EM's can be ported ~15% by stitch-welding the outsides first, but it takes some patience and proper technique to do that without warping the flanges.

Ultimately, a pulleyed Series 1 should benefit more from ported EM's than from a ported LIM.

Porting/smoothing the outlet of the SC would be for reducing SC outlet temps.

LakevilleSSEi 10-30-2005 04:25 PM

Did you get any MAF reading before and after the porting?? I'm not tooo worried about the EM's needing to be ported, but the car is gonna be going into the exhaust shop soon, to get my cat installed, and the rest of the exhaust buttoned up and completed.

After that point if need be, I can remove the manifolds and port them too. Or maybe I could just have it done at the exhaust shop irregardless of wether or not it's necessary and just get it done.

You ported your EM's right?

LakevilleSSEi 10-30-2005 07:10 PM

Either I'm stupid, or I can't find you're threads Bill.


If you could can you link me to them?

willwren 10-31-2005 01:00 AM

Porting the EM's on a pulleyed series1 will be far more important than anything else in the exhaust including the cat and muffler.

http://www.bonnevilleclub.com/forum/...hlight=porting (supercharger outlet)

http://www.bonnevilleclub.com/forum/...hlight=porting (TB stage 1)


http://www.bonnevilleclub.com/forum/...hlight=porting (TB stage 2)

http://www.bonnevilleclub.com/forum/...hlight=porting (LIM and misc)

http://www.bonnevilleclub.com/forum/...hlight=porting (Exhaust Manifolds)

LakevilleSSEi 10-31-2005 01:28 AM

Thanks Bill.

I'll get crackin' on this stuff tomorow evening. Injectors are also leaving tomorow AM.


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