This may be a touchy subject

[tann3r]

Ported blowers...is this generally a bad idea or was it solely due to the porting done by BRP?

A buddy of mine that has a 04 cobra mentioned that alot of the cobra crowd send their m112's off to get ported and said that they see about a 10% power gain. he recommended these guys Steigmeier (http://www.stiegemeier.com/home.html).

Does anyone have pictures of the blower Ari had ported by BRP to see what was actually done? Did BRP do the porting in house or have it ported by a reputable shop?

Any comments are greatly appreciated.

[99mx5]

First of all, porting of any kind will void your Magnuson warranty. I would not recommend it if your blower is still in the warranty period. If you are out of warranty, a port matching of the TBA and blower inlet would help. The blower inlet could be smoothed, but its shape should not be altered.

The 7th and 8th pic show the port matching of the blower inlet.

http://www.cardomain.com/ride/810280/5

The intake manifold runners could also be gasket matched to open them up, but the conical shape of the runners should be preserved.

The 8th picture down shows the runners gasket matched with the inner edge rounded like trumpets. The 9th picture shows the rounded edge of the top plate to smooth air flow from the blower outlet.

http://www.cardomain.com/ride/810280/3

With no other changes, I got 10WHP with these mods. I had 188WHP with a old powercard, a 100mm pulley and no E-cool back in the day.

Edit: I later noticed that newer blowers had smoother inlets and better machining on the outlet so porting on the newer blowers will have a smaller effect on performance.

[Satisaii]

I had a BRP ported one. I put a new blower on and made 10% more power.

[tann3r]

Thanks for the info. Do y'all have any pictures of the porting done to the blower? I am wondering what they actually did when they ported them.

It's well documented that the BRP porting caused everyone to lose power. My question is there power to be gained through porting done by a good shop.

[Tom @ Fast Forward]

We also replaced Ari's ported blower.

[FormerDatsun510Man]

I'm not convinced porting would do anything positive. I match ported the blower on my Coldside. The inlet side originally stuck out past the TB adapter by about 1/8" or so and thus I thought theoretically it was hindering flow. I also rounded the edges on the four ports in the manifold. Net result? I initially lost 3-4rwhp with the same fuel settings, then I richened it up and managed to get exactly the same rwhp as before. Interesting... :biggrin:

FWIW, back in the BRP days when we managed 300rwhp, it was with a ported blower. However, the big difference with that one was that we filled in the internal blower bypass with J&B to smooth it out. I think that likely accounted for 99.999% of the improvement in rwhp in that particular setup. Personally, I wouldn't touch the blower V outlet as that is a special shape for the way the air exits the blower. It matches with the particular shape of the rotor. I think any changes there would likely mess up the outlet flow. Thus, I don't think there is anything that I would want to do on the outlet side of the blower. On the inlet side, probably a match port and a little clean up of the rough casting, and perhaps some removal of the machined area of the bypass hole to smooth the air going into the blower. However, I would be cautious with this and there are no guarantees that it would net you much gains. You might find results like I saw... 0.0% :biggrin:

Bill

[99mx5]

I smoothed and matched mine and gained 10WHP with a 100mm pulley, then I got it ported and lost 10WHP. Tom upgraded me to a 105mm pulley and Ecool to get the power back as before. I sent the blower back to BRP and got a replacement from Tom. I ended up making more power with an unported blower, 105mm pulley and ecool.

Like Bill, I was looking to get the most efficiency from the kit and seized every opportunity. It was a lot of work for little gain. I replaced my header and exhaust and saw approximately 5WHP gain but at the cost of more exhaust noise. Lastly, I added the CAI. I think it was the most beneficial because of the added ping resistance when I used the AC and when on the track.

[tann3r]

I looked through the site I linked in the first post and it seems lilots lot of their porting is to the V outlet. I have been looking around for reviews from other mp62 cars like the Elise/exige, mini, cobolt, etc. but have not really found anything one way or the other.

For the m112 in the cobras and lightnings they say they are seeing lower post blower temps in addition to more power.

I guess I'll put this off till I run out of things to do.