Gernby

I autocross and track my car as well, so I fully understand that you want power delivery to be smooth without worrying about accidentally crossing some threashold where VTEC will engage mid corrner and unsettle the car. However, that's all the more reason to get VTEC engagement "right". If you simply set the engagement point at the optimum RPM at WOT then set the VTEC window and VTEC engagement thrreshold using MAP pressure as you desire, you won't ever have to worry about it. I never feel VTEC engage regardless of whether I'm at full throttle OR half throttle.

I understand that your current engagement might feel somewhat seemless now. However, you might be missing out on a big "resonant hump" of power below your current engagement. I had my VTEC engagement set at 5500 RPMs for a while, since I started at 6K and lowered it 100 RPMs at a time until it felt seemless. However, when I later used the "right" method to find VTEC engagement, I discovered this big resonant hump between 3900 and 5500 RPMs that I was missing out on. You can see this easily in the graph below, where I have plotted my low cam and high cam fuel curves. Both of these fuel curves produce a VERY flat AFR, so if one curve is higher than the other, that means it will also be making more power. You can see how close those cuves get at 5500 RPMs, but how they actually cross at 3900 (my optimum VTEC engagement).

nzdannyboy

Hi guys,

just a newbie but I have been trying to do some homework on extractors for the F20c and this thread was very useful. The thing for me is I have fitted the engine and box into a small old school race car and off the shelf products are not an option. I have the car running but am about to dry sump the engine and move it to where it is best in the engine bay. All I did to get it running was to modify the OE set and make up a fairly budget air intake, not understanding the dynamics of the engine fully I dropped about 30 HP So this time I would like to get things correct. I want to get the lenghts of the pipes correct and as close as possible to a set that works, I have been trying to do a scale drawing of the J's set off the above pic but it is hard to know how far off I am. Any help on this would be really great.

I think Primaries are 357mm x50
secondaries are 260mm x50
and a tapered collector 150mm 55/60mm

cheers dan

xrapidx

Do any of you guys think Skunk2 will ever release a header? They keep saying 'soon'... for over a year.

alSpeed2k

^lol, just buy something else, there's so many other ones out there!

xrapidx

Yeh - but I was going with a Skunk2 theme.

But I recon its vapourware by now.

Gernby

Dude, you need to abondon the theme! If you care about performance, buy the right parts, not the right brand. No single company has the best of everything.

alSpeed2k

unless of course Skunk2 is sponsoring your car!

red@9k

Does anyone know if the gasket J's racing provides with their header is the same one used on OEM manifolds?

xrapidx

Part supply down here in South Africa is tough - I can get Skunk2 and Megan Racing without paying an arm and a leg.

The reason I've been waiting for the Skunk2 Header is I'm hoping it will show decent results when used with a Skunk2 exhaust and Skunk2 test pipe - although I think its time to move on.

I'm open to other suggestions to compliment my current setup of a Skunk2 exhaust, test pipe and K&N FIPK

alSpeed2k

I think Skunk2 & Megan have lower price points, especially compared to the JDM stuff, everywhere.