The 16X engine seems to have 2 exhaust ports. It would be interesting to see more details.

Did you nitrate coat the end plates

 

Two per iron?



looks lie the same as the Renny

I am interested in the lack of aux ports though

 

I thought your old one were loose as well

 

Ah I see Bret--is the sleeve thickness the same?

Harlan and HF999--I get it. Thats why I said never mind--- but that small bit of higher back pressure is work lost. May not be enough to be concerned with until you start boosting--then that siamesed center port could raise its little ugly head.
I think Bret "saw" something earlier and is doing a field experiment to collect more data?
Have any of you used a thread wand to study the air flow through these areas?
Use one and you will see turbulence in the centerport versus the end ports--now what that means and what affect it has overall--i am not sure.

 

You got it OD . I've pretty much already tried this - accidentally . Now I'm doing it on purpose with a bit of design thought thrown in .

I'm expecting to make 20-30 more whp at the same flow . If that happens ,and it doesn't cook the side seals ,it will have huge implications for the 400whp hopefuls.

 

i remember when you posted a picture of the center port "tongue" that was gone--at least I think that was you...dang old brain.
I sure will be interested in your findings.
keep your oil temps to 200f or less on its return to the engine and that will help the side seals a little. Not a big world of difference --but a little.

 

yep , that was me .

 

pretty sure I can see an aux port there .................

 

I see the runner for one, but in the other pic I don't see the actual port

 

That is because in that pic you are looking at the centre iron , which doesn't have an Aux. port.

 

if you look closer at the AUX port, two sides are flat, look even closer and you can see that it doesn't go all the way through, its only an indent,

really it means nothing, it could just be an AUTO 16x prototype.

thats my .02

 

Here's what I've got so far. This is a trash iron. Chiseled out the center divider to just inside where the port opens. Need to clean it up, but this is the design I plan on using in my rebuild.

 

/\ wow - chiselled it huh ?

 

yeah, i drilled a line of holes where I wanted it to end then drove the chisel down each side until they met. Not pretty yet.

 

This just in, I'm an idiot.

 

Why are you doing this?

 

Because with the divider in place the center port sleeve (which is already smaller than the ones on the ends) is half as large. Darn restrictive if you ask me. Brettus claims hp gains and i don't doubt it, I think cutting this divider back so it only prevents exhaust from hitting the other rotor will give decent gains without changing exhaust timing and while having no effect on scavenging. Worth a shot anyway.

 

Bret--if you dont have a true 3 inch exhaust --get one--it makes a noticeable difference.

 

/\ can you elaborate OD ? What real world gains have you seen ?

 

I'm curious as to what exhaust set up you have brett

 

numbers to follow at some point--but sometimes you really dont need the numbers old friend.
Its that obvious.
I went from the oem manifold, mazsport midpipe and RB catback.
to a aftermarket header with 1.75 primaries, slip on 3 inch merge collector, removed one resonator from the midpipe and eliminated the flange between the catback and midpipe..
No chokepoints etc now and its straighter.
https://www.rx8club.com/attachment.p...1&d=1352603671

teaser pic but you can get a rough idea--this was before i put my heatshielding on it.
change is apparent from 3k rpm upward.

 

OD who did your exhaust work?

 

i gathered the parts and local shop did the wielding with my instructions/measurements.
Sorry for the thread jack Bret

 

Dead end path. Racers burned out the center port divider NA, which in turn then burnt out the rotor seals. Without the divider the center iron exhaust flow just slams into the opposing rotor side face. FI will be that much worse for wear ...

 

/\ Thanks for that - hopefully my design will be better than that ....