Hey guys, i was just curious what some of you higher HP FI guys are activating their Vtec at. I was just curious to get some opinions, theories, and suggestions. Right now, i have vtec @ 5800 and i shift @ 9000. any suggestions welcome, thanks!

 

my "vtec" is when my turbo kicks in, woot! lol (geo's dont have vtec)

sorry this doesen't help you.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lazerus &raquo;</TD></TR><TR><TD CLASS="quote">sorry this doesen't help you. </TD></TR></TABLE>

Correct, but good try.

 

Mine is set at 5200 on the street car. vtec spools the turbo instantly!!

 

same.....5200; as soon as vtec kicks in my tires break till revlimiter (on street tires of course)

 

With few exceptions, 5200-5300 seems to be the most ideal vtec s/o point with single runner intake manifolds for turbo apps. On s/c, you can set them as low as 3200rpm, sometimes lower, with no adverse affects.

 

Well i can see what the popular choice is, I was more or less looking at it from a tuning perspective, basically

 

What exactly is considred a High HP Turbo Car? Just curious. Would I notice any gains switching from my Factory 5700RPM S/O to a lower one with around 280 at the wheels?

 

5200 dude

 

I usually turn it on around 4600-4800, but there are alot of variables that affect what works best. Higher compression will allow you to lower it a tad and big cams will of course need it higher. The gsr i just finished that made 372 @ 9psi is set at 4800. Our race car is a little lower than that

 

Wouldnt it be best to have the vtec xovers for the cams? whatever the cams make the power..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by len &raquo;</TD></TR><TR><TD CLASS="quote">What exactly is considred a High HP Turbo Car? Just curious. </TD></TR></TABLE>

Good question, i guess there really is no true answer to that, hehe. Thanks for the replies guys.

 

are sohc turbo applications lower? I have heard of it at 3200 in the f22b1.

 

I have mine set at 4400 and there is absolutly no dip in the power band.

 

I don't have a high hp car but mines set at 6k rpm, it actually switches about 5,800 rpm. Thats where i got the least dip in the power band (lose 1-2hp vs 14hp when it was set at 5,200)...
I guess it all depends on your set-up, the more built engines seem to set it closer to stock, while the non-built street cars seems to run it higher (closer to 6krpm). may have to do with flow,I just set mine where it makes the best power and the least adverse effect.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b16ahybrid &raquo;</TD></TR><TR><TD CLASS="quote">I don't have a high hp car but mines set at 6k rpm, it actually switches about 5,800 rpm. Thats where i got the least dip in the power band (lose 1-2hp vs 14hp when it was set at 5,200)...
I guess it all depends on your set-up, the more built engines seem to set it closer to stock, while the non-built street cars seems to run it higher (closer to 6krpm). may have to do with flow,I just set mine where it makes the best power and the least adverse effect.</TD></TR></TABLE>

Great information.

 

i dont own a high HP car but mine is set at 4800. being that i run a d16 plays a role in that.

 

mine set at 4900 work perfectly for me

 

My vtec is set to activate at 4800 because I have found the it's the most ideal place.

 

Ron, what broke on your dyno run?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boostsohfast &raquo;</TD></TR><TR><TD CLASS="quote">Ron, what broke on your dyno run?</TD></TR></TABLE>

Well last week, it was the manifold that was at fault. This week the vtec relay was flickering on and off and also comming on at different points on different runs. I have fixxed the problem, but now im trying to figure out where to set it at now that im running an external activation switch. Maybe next week ill get it right

 

mine was lowered to around 5000 rpm but i don't know exactly where. i tried to listin to hear when it kicks in but it gets way to loud and crazy at that point. short dump tube and the turbo spoolin are way to loud to be able to hear the vtec x-over.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SIXTYdashONE &raquo;</TD></TR><TR><TD CLASS="quote">

Well last week, it was the manifold that was at fault. </TD></TR></TABLE>
What was the problem with the manifold and what did you do to remedy it?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boostsohfast &raquo;</TD></TR><TR><TD CLASS="quote">
What was the problem with the manifold and what did you do to remedy it?</TD></TR></TABLE>

The manifold wasnt holding boost well. In fact it would hold solid at 18psi, then when i hit 7400 rpm's or so, it would shoot up to 24-26. Since it was a divided housing manifold and a divided housing turbo, the wastegate was only plumbed to runners 1-4. I had Crazy Gary weld an extra elbow from runner 2 to the wastegate elbow. Held fine at 22psi after that. Now the manifold looks like the one pictured below (bad pic, but u get the hint). I can take more pictures if nescessary.
BTW, Picture courtesy of TurboDandee.

 

Hey man, i have a better pic than that... if someone would host it for me. Im glad you fixed your problem