Thanks again everyone for your input. I appreciate it. I can weld so I will be welding all the intercooler pipes.exhaust pipes. Downpipe, etc.

Email me for the list of current options and costs. This is constantly changing as I find cheaper vendors, sources of raw material, and my attitude.

Your attitude couldn't have been cheaper a year ago?

It most certainly was cheaper a year ago, because I like you.

Gosh, I've never seen so many people bash the BEGI cast iron manifold before. What got into everyone all the sudden? It is one of the best available and has the best history of any manifold, ever made for the Miata. 16 years and two unexplained failures. There have been other failures, but those can be attributed to too much ignition retard. Too much ignition retard will kill/crack any manifold. That said, it has to take alot of abuse in order to crack it.

I think the true test of durability - is that all of the 400 hp plus miatas running a cast iron manifolds - are using the BEGI manifold. The first 600 whp Miata was running a BEGI cast iron manifold. Short of dropping it on the floor or retarding too much timing, it is nearly bullet proof.

As for flow, the only one that potentially has us beat is the absurd flow manifold. It is pretty spiffy, but not a cast iron manifold. Time will tell how the welded ones hold up. The FM manifold has more bends and angles to it, therefore it will flow worse. It also does not have the divided pulse feature.

As for reliability, I can just about guarantee you that an FM manifold will break studs. 8mm studs do not last that long even for street use. Been there, done that, and learned that lesson. We have been using 10 mm studs for a few years now. The only people that have problems with the 10 mm studs are the racers. That could very well be because we were shipping grade 5 studs instead of grade 8 studs. That problem is fixed now though. The grade 5 studs got thrown in the garbage and the grade 8 studs are shipping with ALL the turbo kits and manifolds. However, they still seem to have a stud stretching problem. Corky's investigation continues. I, personally, do not track my car and have never had a loose nut or stud problem. I put lots of miles on it, but no track use. If I had to choose between an S4 manifold and the cast iron one, I'd probably choose the cast iron for the reliability factor.
Stephanie

I'm always the first to say that my BEGi kit was 100% reliable on the street. I never had to put a wrench on it once. Even after track action, the only parts that failed were the studs...and that says a lot considering the demands I've put on it.

Now, for a discussion that hinges upon untested equipment that may, and probably will fail on the track, lets just pretend that v-bands work for a moment:

I don't want to deal with taking the turbo manifold on and off to replace studs 5-hours from home, and sending the manifold to the machine shop each time to get it fixed. Considering that BEGi now makes a V-band kit there is no reason to deal with cast iron any longer in my esteemed opinion. They warp, the studs break/stretch, so why anyone would spend money when there's as absolute solution from one of the big vendors? Of course BEGi should keep selling it, but "I told you so" for every person who experiences this problem when either BEGi or Tim are making manifolds which circumvent this problem. Its 2009, every competitive racing team is using V-bands, so now its time to evolve. The turbo miata world had a revolution this summer, I embraced it.

If I could turn back time, I would have started with V-banding (or stay naturally aspirated like I knew I should have) and never had any of these problems but after the amount of money I've spent trying to make it through 1-session on a cast manifold it would be foolish to go with anything but v-bands. If the V-band kit fails, I've learned a roughly $6k lesson just in turbo parts alone. I'm going to cry and cry over it...but I'm selling everything and buying an Evo-9. Get ready for the fire sale.

Looking at the Begi V-Band downpipe, why is the wastegate exhaust reintroduced immediately after the turbo exhaust? I was just wondering if this could be one of the reasons for the vband setup lacking power...

Nope. It has more to do with a turbine housing that is possibly the wrong size. Or a turbo inlet of 2.5" instead of 3", etc.. The turbo has the smaller a/r turbine. The car makes 267 ft/lbs torque at 4200 rpm (fun to drive!!!), but starts to fall off.

I did ask Corky about that too, just to be sure. :)
Stephanie

Because their jig can't handle a better design.

I wish I could afford that #2 for my IHI ;~;

Maybe someday.

you guys should block off the WG exhaust inlet into the DP and run a completely separate "screamer pipe" from the WG.

it sounds kind of like the car gets up to full boost and then the WG starts opening and screwing up the flow behind the turbine and flow/power starts to drop off... I really don't like to contradict Corky, but it just seems like a relatively valid theory.

what a/r turbine do the s4 kits usually have?

We made this pipe strictly off the jig from the standard SG DP. Since Tim did not know how it would fit, he built the vent tube shorter. But seeing as how be built it off the jig, and no car to test fit it on, he did a damn fine job. It fit perfectly. Went straight down the middle of the tranny tunnel.

.86 A/R. This one has a .64.

Also, we do not think it is the downpipe, because the pipe is already larger than the normal pipe. It is 2.75" pipe right off the turbo. Most are 2.25" off the turbo.

Stephanie

Yeah, I am pretty sure it was just me being stupid and not going with a larger A/R. I may get to upgarde to a 2871 sooner than I thought :hs:

dont buy a boostlogic manifold is my only advice, pure crap
here is the gem of a merge collector they put in it
Attachment 203886
Attachment 203887

its a $900 paper weight
i sent it back

if you live near NY hit up synapse motor sports, here is what they build me
Attachment 203888
Attachment 203889

Ohhhhhhh very nice, I hadn't thought of that turbo location, I like it. How much did that manifold run you?

Got any shots of the synapse collector? That really is one of the nicest looking Miata manifolds I've ever seen.

mmmmm, I like a lot.

I like that synapse design.

I've spent a significant period of my life under the super-miata with the Boost-Logic manifold and although it looks like shit, its made crazy #'s and the connecting hardware never loosens on race-day. But yeah, it looks like shit.


Tim...going to change the v-band design any? I like the location of the Synapse manifold better (dear god intercooler pipes will be easier and I won't have to change my water inlet neck), but at this point you could give me a hunk of shit with v-bands on it, and as long as it stays together, I don't care.

It's cool if you dont mind the extra 3 feet of downpipe burning your hood off... maybe facing the comp inlet a little more forward would straighten that first DP bend out...

Are you talking about the SCC Miata?