TurboTim

iTrader: (9)

http://www.flyinmiata.com/index.php?...21020%20%20DUC
$395 FM mani

http://www.bellengineering.net/produ...products_id=33
$433 BEGI mani

http://www.absurdflow.com/begireplacement.html
My direct replacement for the above 2 is $600 (egr extra)

But yeah, my mani & downpipe together, to bolt onto a factory type exhaust would be $450-500 more than FM's mani/downpipe combo.
http://www.flyinmiata.com/index.php?...0%20%201990-93
FM's mani & downpipe, $750

I would like to know what the inside of the FM mani looks like as well. Perhaps Keith will chime in with a photo. A quick email to them usually results in what you're looking for.

I don't see anything personal about your posts.

soloracer

iTrader: (10)

By "personal" I meant that I could have just asked techie questions and left my situation out of it. It's my loquacious nature.

I got that figure from kit and partial kit prices that were quoted to me. It's the difference in a full FM kit with 3" exhaust and the same kit minus mani and replacing with yours. Individually, you're only like $200 different. When I was looking at those numbers, it was an easy choice to send you a check. :-)

soloracer

iTrader: (10)

Let me qualify that figure by saying it's off the top of my head. I haven't had time today to actually do the math.

If it really comes down to $200-$250 I'm going AF.

FRT_Fun

iTrader: (19)

You can check the spool data in the spool data thread, you might get some insight into how well the manifolds flow. Not sure if there is any absurdflow stuff in there or not, but I just posted up my data with the FM Manifold. I'm sure there is more to it than that, but maybe just a piece of the puzzle.

TurboTim

iTrader: (9)

I'd like to see the first post in this thread placed on the turbo section of miata.net, and see their responses. FM looks at that site a lot more I think.

Besides what's sitting in my garage at the moment, there's only 1 AF replacement mani out there ("version 1"). I don't know what the current owner has done with it if anything. I do know his signature is "absurdflow log manifold" which it AIN'T. I dynoed it on my car and got good results compared to an equivalent BEGI setup on the same dyno, but that's about it. No FM stuff around this area it seems.

soloracer

iTrader: (10)

I'll post it over there just for fun.

soloracer

iTrader: (10)

Modified a bit and posted on the stuffy board.

JKav

iTrader: (1)

The popular notion of 1 and 4 'colliding' in log manifolds always makes me laugh.

Braineack

iTrader: (62)

I mean obviously the exhaust will just flow into the turbine...I was just being funnz. But it's no joke that a good collector makes a world of difference...it's been seen here time and time again.

wayne_curr

iTrader: (8)

I've always figured that it cant possibly be that bad since so many people run log manifolds with good numbers. I can understand it in my head visually, but cannot explain it.

JKav

iTrader: (1)

Yeah, I hear ya. It is funny. It's troof that proper collectors make a big difference.

soloracer

iTrader: (10)

Yeah, I've wondered about this. I really kind of took it for granted that it was significant since BEGI went to the trouble to put that divider in their manifold, and people bring it up all the time.

Since the cylinders don't fire at the same time, is it really a big deal?

JKav

iTrader: (1)

It is a 'big deal', but not because exhaust pulses collide (they don't because only one cyl fires at a time).

The big deal is that logs dissipate pulse energy and encourage cylinder cross-talk. When you have a proper collector, it is much harder for an exhaust pulse to reverse direction up another cylinder's exhaust runner. In turn you get more pulse energy directed to the turbine and less of it trying to contaminate other cylinders.

Collectors are good mkay?

Doppelgänger

iTrader: (12)

I am running a newer FM cast tubi. No problems from me. Then again, I am not Mr. Ever Last HP...I'm running 13psi on it with a 2560R and can say I am happy with it..doing daily driving autoX and some track days. I had an older FM/BEGI design one and I can feel/see a difference between the square design that BEGi is still using and the new FM design.

Sorry, no pics of the inside.

soloracer

iTrader: (10)

Didn't you break both of those?

Doppelgänger

iTrader: (12)

I cracked a BEGi/FM square one, broke a newish FM tubi....but the latest FM one is holding up just fine (they switched foundries). I have a few ideas as to why the first cast tubi failed, but I don't want to go into it...but I will say if I thought it was bad quality, I wouldn't have put another one back on.

Fm has had two versions of the cast tubi. The older version had a boarder around the FM logo, the newer cast ones do not. The newer ones are also improved when it comes to bolting it up to the head, FM made sure to make the studs/bolts easy to access/tighten. I wanted to kill the other two manifolds when it came to a couple of the nuts...but when I put this last one on it was much easier to do it becuse of some minor design changes.

soloracer

iTrader: (10)

Thanks! All good information.

boileralum

iTrader: (8)

I didn't realize I had the only one, and sorry about the mis-labeling in my sig, Tim. I haven't dynoed my car, I am running the stock wastegate actuator on my T25 (which I couldn't run with the previous FM manifold) at the stock 8psi or so level. I have no complaints at all about it, I love it. It is easier to install than the FM mani, weighs significantly less, and allowed the stock clocking of the turbo so I could get rid of my crappy hacked bracket and ebay actuator. Fit is perfect as well, my FM downpipe bolted right up with no leaks and I didn't have to adjust anything downstream in the exhaust. I wouldn't hesitate to recommend it to anyone.

TurboTim

iTrader: (9)

Ha! Nice, I should use this under the "testimonial" section of my website, if I had a good pic of your car too. nice update to the signature too I'm glad you like the mani, I sure did when I used it for that week. Once I sell the twins I'm going to rock that manifold again

EDIT: Did you notice any spool difference with my manifold, or "seat of the pants" difference in power at the same boost setting?

soloracer

iTrader: (10)

Yes! Tell us how it feels. I assume the version 2 will be more difficult to install, but I don't think I care much.