porting the plenum

[geogolf]

hey guys i need help again, i bought some slp runners for my 90 L98 mostly stock vette, i started around 9am to take plenum off to port. not quite as easy as some of you said it was but i did get it off, hope someone can answer some ?s i have there are 2 bolts that you have to take off to get runners off, that are under the plenum 1 frt 1 back. when i go back togeather do they have to be put back in they were a pita to get out not sure i can get them in also is there a link to show how to port the plenum did a search but did not see a definate way to do it any help will be greatly appr. geo. ps any sugg. are welcomed

 

[ZumZum]

www.geocities.com/jgkov/index.html

Some good info on this site

 

[Edmond]

Would it be easier to take get to the lower runner bolts if the valve covers were taken off?

 

[G Winter]

which two bolts are you talking about ?? I just had my intake off this summer and really didn't have much trouble. There are two bolts that hold the runners on that you have to have the plentum off to get out.Might be you need a swivle to get them out.You MUST have all the bolts in place or it will leak or even worse might break something.

Glenn

 

[geogolf]

porting plenum

that the two that were a pita. had swivel just hard to get at so i will put all bolts back in, just a sidenote received my slp runners today from summit. one had a 1 inch crack in it called they said shippers fault, probally happened at factory anyway they are sending me another set will be here wed. thanks for your replys geo

 

[vetteboy86]

Porting it is really no big deal. Just look in the end and hog it out with a dremel or a drill. I used the die grinder with the air compressor.

 

[Edmond]

I'm probably going to port mine next weekend. I'll do the runners and the intake as well. I've already started on the intake ports on the heads. I have the gaskets and I'll match the intake port to that.

Anyone have an estimate of expected gains?

 

[vetteboy86]

I think there are gains to be made by this simple mod. Offcourse though Edmond, you opened yourself up to all kinds of opinions. I wish I could have the car dynoed after each modification I do.

 

[86PACER]

Here's another good walk thorugh with good pictures.
http://www.gmtips.com/3rd-degree/dox/tips/plen-port/port.htm

 

[Edmond]

Here's another good walk thorugh with good pictures.
http://www.gmtips.com/3rd-degree/dox/tips/plen-port/port.htm

Thanks for that great link!

Right now, I'm even debating whether I should just splurge for the Edelbrock base and runners with my own ported plenum instead of porting the stock base and runners. I don't know, I guess it'll depend on how I feel at the time. But knowing my impulsive self, I'll probably end up getting the Edelbrock! :L:L:L

 

[bossvette]

SLP and most likely others sell a long ball end Allen wrench to make those bolts easier to get at; you can turn the wrench with a socket.

 

[Edmond]

I'm actually going to disassemble the whole engine and have it rebuilt. As to what specs, I don't know yet. If things really go well, I'll have a 383 built but my father doesn't think I'll need that. Do I really need a 383? No, but do I want it?

But I'm probably not going to go the 383 route since I don't want to spend the money for it and a 350 can provide plenty of power for my type of driving. My goal isn't a high horsepower motor, all my driving is local driving so torque is my goal.

I have a set of 3.45's which will definitely give me a SOTP feel from the 2.59's right now. It's going to be a fun winter!