Utah S2K

Sounds just like what Mark DiGrappa is doing???

IMHO don't regrind cams or you'll be sorry

Utah

Team Hybrid

Geez!

At first I was thinking to myself, hmm, sometimes when the head is overtorqued or undertorqued, perhaps, that may cause leakage. But damn. Sounds like its way beyond that.


I guess we'll have to see ( if I ever get my Turbo kit in.. ) what we can do with stock compression and the AEM EMS.


In regards to Chris, and his wild adventure of the engine rebuild..very excited to hear about your decision.

by the way....did JE mention anything about their pistons working with the stock rods?

cjb80

They will work with stock rods once we figure out exactly what we need... everything at this point revolves around getting a measurment from the top of the piston to the top of the pin.. Once I get that then we can talk with JE again.. we are waiting on the Helm manual to come in at this point. If the diagram isnt in there then we're going to have to take my engine apart to get one (which we will do anyways, but I think they wanted to get the parts in before we started that) or we will have to buy a piston from Honda..

Also, All Data doesnt seem to have any piston diagrams ethier..

I am not sure what mdigrappa is doing these days, it's basically what he had in mind, but the time and money that he claimed was required from his suppliers isnt anywhere near that which I am spending from mine..

Chris

The Reverend

Sorry to hear it didn't seal, although I have to admit I had my doubts about a copper head gasket on a street car that isn't o-ringed.

Chris, I have only ONE piece of advice though - LOOSE THE LOG MANIFOLD! I have a friend that used a log manifold on his Prelude and SWORE that anyone who knew anything about turbos would agree with him that it was a good solution. Well, he has since asked several major import drag racers about the subject and learned you can loose a good 30-40 rwhp on a log manifold vs. a good equal length manifold at the same level of boost. I can't say how much exactly you are loosing, but if you're going to go through all this trouble rebuilding the motor, I suggest you fix the manifold too.

Anyway, didn't mean to tell you your business or anything, but every time I heard what you dyno'ed or anything, all I could think is - "Imagine what that thing would do with a good manifold".

cjb80

Hmmm.. Interesting.. I asked Dwight about it acutally a while back because he apparently had one in development but quit working on it. He said that he would make an equal length manifold for about $1500 bucks because it requires about 40 hours worth of work. I believe there are places in Miami that will custom make equal length manifolds for like $400-$500 bucks though.. Dwight said it would only make a difference of like 5 hp or so, which obviously isnt worth the money.. Do you seriously think that it would make a difference of 30-40 hp????

That's a pretty big gain, obviously it would be worth the money then.. I just wish I had more to go on besides your suggestion..?? (I have doubts, but I honestly don't know ethier way)

I know that Twin Entry turbos are even more effective/efficient than equal length manifolds, what do you think about that?

Chris

The Reverend

I really don't know TOO much about turbos... I don't really like how they drive, so I've never looked into them much... But I have heard from several very reputable sources that the hp difference with an equal length manifold vs. a log manifold is BIG. Enough that I've heard you can run about 2 psi less and still make slightly more power than with a log manifold. Like I said, I really can't say exactly how much you are loosing to that log manifold, but I would put my money on "a bunch".

$1500 sounds a bit pricey, particularly since you have been the guinea pig for a lot of speedcraft's r&d (so I think they owe you a better deal than that). Under $1000 is about right.

Ask around. If you're not going to go with an equal length, I suggest at least something with a collector to merge the gasses. Just look at how the log manifold works - everything just gets squished together instead of flowing together. It always screams bad design to me.

Anyway, if you need people to contact for info, pm me... I'll try and get you in touch with someone who can speak to you on this subject with more experience than I have.

derryck

You can buy one from Kiwi (in Calif. I think), they did the one for that Silver S2 that was being tc'ed by Atomic. They (Kiwi) will sell you a tubular manifold for around $1200 but you would have to talk with them to determine how difficult the 'flange' issue would become. I can't see Dwight being very far off base on his estimates on hp loss but maybe he is just opposed to doing the tubular due to the vast amount of man hours (in this case, Dwight hours) involved and is trying to skew things in his favor.

Team Hybrid

doing a tubular manifold like kiwi's crazy setup seems really hard on space. There isnt much to work with from the start. Because of all the lines.
Also, didnt the atomic S2000 have a log style as well? As I recall from pictures...it did.

I think kiwi had another style as well. As I recall seeing in import tuner. Where the manifold branches out towards the radiator. If thats the case, I guess kiwi would also have to fabricate a custom downpipe and intercooler piping for that app, since the turbo would be placed more towards the radiator as well.


40-50 hp gain huh......hmm Ill have to see that one.

Another important factor in regards to log style manifolds is also dependant on where the wastegate is located. For example, DRAG places the wastegate on one tube (primary, or whatever you call it) instead of in the center for better results.

from many I have spoken with, many tuners, recommend goign with a turbo manifold that incorporates the wastegate to be located in the middle or center of the manifold, where the exhaust gases meet.....or something like that .. to be more efficient.