I was wondering which will be better? I was thinking of a b20 vtec turbo, then I heard Vtec was hard to work with turbos so a b20 turbo would just be fine right? Which one of these will be more reliable and better in the long run? Also is vtec all that in a turbo motor?
Is VTEC reliable in a naturally aspirated Integra???
Re: Vtec turbo ro no vtec turbo?
Originally posted by BoyRaCeRs
I was wondering which will be better? I was thinking of a b20 vtec turbo, then I heard Vtec was hard to work with turbos so a b20 turbo would just be fine right? Which one of these will be more reliable and better in the long run? Also is vtec all that in a turbo motor?
Well,
One of the big reasons why VTEC is hard to tune with a turbo is because of its high compression ratio (normally starting at 10.4:1). Otherwise, I don’t see any other reliability issues versus Non-VTEC setups.
Regards,
Oz
Actually, the issue with VTEC turbo, is the cam profile. VTEC cams have long Overlap and Duration lobes, which are not condusive to Turbocharged engines. The fact that VTEC cars tend to have a higher c/r is also a reason.
Rob,
Please expound on this issue. If you have cam gears the overlap can supposedly be tuned away.
Please give us details.
TIA
John
What if you disabled the vtec-ness of your vtec engine and just stayed with the low rpm cam profile the whole time? You’d still have the high rev ability and the great flow characteristics of the vtec head with what I assume is pretty close to an LS cam. I’m not sure though, I’m really just making this up.
Originally posted by AMERIKAN
[B]Rob,
Please expound on this issue. If you have cam gears the overlap can supposedly be tuned away.
Please give us details.
TIA
John [/B]
Yes, your right. Excessive overlap can be tuned out with cam gears. But remember, an overly aggresive cam (like ITR’s) require alot more tuning than a stock GSR cam will(to tune out the overlap) with an FI engine. The problem is, typically when you adjust cam gears you can adversly affect the power in another portion of the powerband. So in fact your peak horsepower may be higher but you low or mid or both could suck. The B!itch of the thing is, when tuned VTEC under boost is awesome- as you already know John. That is why you wouldn’t want to necissarily “tune out” the VTEC.
This is just a generic explanation. If I get some time, I will try to compilate a “More scientific” explanation with actual examples.
top tuners swear by stock b18c cams.
boyracer, if you can afford the crvtec conversion, then go for it, if not, then b20 turbo good too.