I have an fb which I am planning on doing a 13b swap. I have a 6 port which I purchased out of a junk yard for $100. I ordered the engine mounts last week. I am waiting to get more money to buy a rebuild kit. I want to give my engine a large street port. Has anyone ever grinded the diffuser out of the exhaust ports? Later I will turbo the engine, hoping to get about 300hp.

 

Yuck, Yuck....bad idea...totally kills flow (impacts velocity). Better to do a streetport, use a gsl se lower with functioning 5&6th ports and pineapple sleeves. Then go with a racing beat upper and a side draft. Purchase a "boost prepped" side draft from Robert at rotaryshack and you will be ready for the future. Look at the attached 6 port pics, this port worked really really well for me. I also have a pic of an "abomination" port like you speak of, not enough side seal support and the end looks like a brick wall, yuck! Compare the abomination port to the bridgeport I run now.

 

Just to make things clear, I didn't do the abomination port, I found the pic on a posting one day.....

 

just do a four port if you have a early motor i may have some plates

 

Can anyone actually prove that there's a power improvement with Pineapple sleeves? I can explain to you why they don't do anything.

defiant13 - You might want to consider Turbo2 housings instead of the NA versions. That little hardened steel turbulence inducer is already gone.

 

Holy lol @ picture 3.

 

I've used them and absolutely feel a difference in smoothness at acceleration and WOT. I dont have dyno numbers to prove this but for $40 lets be serious. BTW I run my ported 6 port carbed, w/ no actuators.

 

That's not too conclusive.

 

True, no conclusive evidence, and pineapple "should" provide such. But just looking at the functionality of them compared to the brick wall and the fact that the rx8 are similar to this has me sold that they would be effective, especially in a boosted application.

 

Here's the thing, when air flows from the intake port into the combustion chamber, the high energy part of the flow more or less "ignores" the back corner of the port anyway. It forms it's own, natural wedge of high pressure air. This is the same principle that makes truck beds more aerodynamically efficient when the tailgate is up then when it's down. Believe it or not, the majority of the flow is coming from the inner corner of the port, not the outer.

I'm not saying that you can't help flow (by a very little bit) by adding guidance to the inlet, but you have to do it very subtly and carefully. It takes flow bench development time and many iterations to get that kind of thing right.

The Pineapple sleeve, from what I can tell, actually makes the opening into the chamber smaller (it's got a "foot"), which is a restriction to flow, not an improvement. And it's taking up way too much volume. I haven't seen the sleeves on the Renesis, but I'll bet that they're not shaped like the Pineapple wedges.

I have a flow bench. I'd be happy to test the sleeves next to each other and come up with some conclusive data if someone wants to send me some parts.

 

Sad thing is, you would think pineapple would do & publish such test results themselves. Makes me think they've done dyno and flow bench testing and perhaps didn't get the results they hoped for. If I made the product and it "worked" I would certainly back it up with testing. Sooooo, scratch my earlier suggestion about using the inserts.

 

Never said I had conclusive evidence. My point is for $40 bucks there isnt going to be a whole lot of performance info on these inserts.

 

that 3rd picture is ghetto

 

that last pic needs a lot of work...

 

WTF, pardon me? It is not cleaned up, plus it was just a test fit for a pic and with just a camera phone at that.