PontiacBonnevilleClub.com

Does this look sufficient, or does it need more work, or did I already mess it up? If more pics are needed, let me know what area and I will post it. Also, should I plug the silencer ports? I would probably have them welded if I did. Thoughts on this?

doesnt look too bad from the pics. I think you may want more of a 45* angle on the outlet. And may be able to smoothe out those rough spots on the inlet.

but, is it necessary to port back by the rotor bearings?

and imo, I wouldnt touch the silencing ports. Not worth the trouble. performance gain to the cost of having someone tig weld them shut is marginal at best. And the noise would be rather much. If you want to hear more whine, put in a FWI if you dont have one yet, belive me, that is more than sufficient.

edit* http://www.3800supercharger.net/p&p.html
check out bills site for what I mean about the 45* angle on the outlet.

Unless you want it to SCREAM, leave the silencers. You want that fiero at least a little sleeper, lol.

I think that looks pretty good, really. You got the most important part, being the excessive roughness of the inlet.

Wes wrote:but, is it necessary to port back by the rotor bearings?

check out bills site for what I mean about the 45* angle on the outlet.

1fatcat wrote:
You mean this porting? That is the inlet of the blower, looking at it from the rotor side.


So I should open up the outlet more?

00Beast wrote:Unless you want it to SCREAM, leave the silencers. You want that fiero at least a little sleeper, lol.

Ok, I'll leave them. Wasn't too thrilled about welding them for noise, but if there isn't a power gain I'll leave em.

J Wikoff wrote:I think that looks pretty good, really. You got the most important part, being the excessive roughness of the inlet.

I was hoping someone would say that. I do not want to do anymore to the inlet because it really sucks to get in there. I know it isn't perfect, but good enough for a stock cam/heads engine for cripe sakes

Wondering about the outlet though, that is easy to work on. Should I open it more? I thought you start loosing outlet velocity if you open it too much?

It's been a while since I heard the term "S-porting", but it involved enlarging the top point of the outlet opening in your last pic. Maybe it doesn't apply well to M90's. Might warrant some googling...

It looks very good.
Wren should chime in, but do not plug the silencer ports.

derr, sorry. not sure what i was thinking

Don't enlarge the outlet, chamfer it to prevent 90° turns of the boost charge to exit. A 45° chamfer on the inside is a must, a smaller one on the outside edge of the outlet might be a help. Then polish it to a mirror shine. This will help prevent deposits from building up (which can cause hot spots).

Your outlet pic is blurry. Can you post a better one of the inside and outside of it? The inlet looks fine, that's smooth enough. It's only necessary to knock down the high spots left from the casting process.

does your camera have a macro function on it? if so, try to use that, it'll help with super upclose focusing.

job looks great btw, although i'm 100% qualified to make a call on it. most of my porting knowledge is from seeing it done on LS series motors.