Urge

Full disclosure.. I am a vendor..

Just wanted to see if any FI guys have tried headwork as a way to get good gains with out increasing boost?

We have done a lot of S2000 head development with Endyn. We focus on getting more flow, with little port size increase, thus increasing the air velocity. This will reduce spool time for turbos and increase torque for superchargers. Here is some info on our S2000 headwork. We offer packages for both stock 87mm and bored out 88-89mm pistons with custom chambers. We can get 12-15% more head flow with little volume increase which has great potential for increasing Forced induction HP.

RESULTS!!!

2.0L built S2000, 9.0 CR.

Baseline is stock head @ 16.5 psi
2nd line is URGE/Endyn head @ 16.5 psi
3rd line is URGE/Endyn head @ 18 psi

[attachment=33757:endyn-head-work_TURBO.jpg]

@ 16.5 psi, about 25-60 HP & 25-40 ft-lbs gains through out
500 RPM quicker spool (air velocity)
25 HP gains below spool up

Again, this is all with stock valve sizes!!! We stay at stock valve sizes to keep air velocity up which equates to the faster spool and gains below spool up.
The S2000 ports are already too big and making them bigger to gain flow will reduce spool up, even though it will make more power up top
The key is increasing flow (top end HP) and velocity (spool up and low/mid torque)

Here is the flow chart for this head. 13% IN gain, 30% EX gain.

RAIN H8R

Interesting stuff. I am in the market for getting my F20C head redone. I have not decided what Ill do, but at the very least I need guides and valves. Are the prices listed on the site page posted include valves? It does not clearly state what is included.

H4RD ON

I'm interested and have the ability to do a great comparison. I've got a boosted AP1 with a pretty solid turbo kit I custom made. Access to a dyno and very well known tuner that would be willing to take part as well. I have a stock head and a head I hand ported to throw in the mix along with a head that I'm sure I could get Brad @ RLZ to port for the testing.

Send me a message if your serious and I'll get into details. Have been talking about doing something like this for a few months but never really pushed for it.

Brutus

I have a few quick questions.

Have you tried swirl testing to maximize efficiency?
Does this head work negatively effect power levels in the lower rpm bands for street driven cars?
Are there any numbers for higher than stock rpm applications?

thanks !

Urge

If you use stock bottom end and thus 87mm chamber you dont have to get new valves unless you want a refresh. Valves dont make major gains. We dont want to force you to buy new items.

If you want to go to 88/89mm chambers we can make seats larger for a bit more flow with out decreasing air velocity. In that case you will need at least new intake valves.

Urge

We dont do swirl heads for VTEC engines as when you go into VTEC both Valves open simultaneously and thus you really can not invoke swirl. Endyn is an industry leader of swirl development and was designing swirl 2 valve heads in the 70s and 80s that outperformed the market. However, unless you can stagger your valve openings on 4 valve head, you really cant make it swirl. It could work on off VTEC, but that head design would take away power when you moved into VTEC.

As noted on our site, we focus on keeping the ports small and thus have a good increase in velocity with air flow. This will improve torque everywhere and thus your turbo should spool up quicker. If anything, your car should be more streetable.

Im not sure what you are asking about high RPM application? We have posted our flow numbers and the gains should be seen through out the RPM band. They higher you go, the more the gains. We do spin our built bottom end S2000s past up to 9700 RPM.

Brutus

Wow. No wonder... 2 valves open. Aha!

I like to explore the idea of widening the powerband. interested in the dyno results!

Urge

There is no doubt the results will show gains, question is how much. We are willing to rebate for a before and after dyno. Let us know if you want to help.

Sideways

I've been running a modified head for 8+ years. With the oversized valves and port/bowl work it increased flow 16+ percent. This equated to a 16+ percent increase in power.

Kyushin

Whaaa!!?? Man I was told the cost to performance ratio of any head work wasnt really there, only thing id see is a lighter wallet... Damn, already ordered my new valves, if I had know that head work did show results I may have went that route. Definitely in for before and after results of dyno with mentioned head work.