How Long Can Turbo and VTEC co-exist together?
06-05-2006, 09:49 PM
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How Long Can Turbo and VTEC co-exist together?
I am now having a debate with someone of whether not Turbo is more efficient with a VVT engine or not.
We mainly base on the B-series engine for this topic. He claims that as turbo gets larger, compression gets lower and it will be useless for VTEC to exist and may eventually slow down overall output. He said that 350WHP is the limit for existance of VTEC...he's saying that his friend's T88 turboed B18C with 8.8 CR had taken out VTEC because at that compression rate, VTEC is uselss. Can anyone comfirm on this? Because as far as I'm concern, VTEC has nothing to do with Turbo as they have totally separate mechanism, why would VTEC be in the way of big turbo is what I don't get.
I think Steven Papadakis's Civic runs T88 H22A engine, he said that car would not have VTEC as well as the infamous Top Fuel Type-RR S2000/EK9.
His another point of view is that B series engine has short valve stroke distance, and thus not efficient for Turbo. I said that the distance can be altered by changing valves. What's the real deal?
Obviously, I have no clue on Turbo+VTEC setups. So I need yall help and inputs on the theory of such setup. TIA.
We mainly base on the B-series engine for this topic. He claims that as turbo gets larger, compression gets lower and it will be useless for VTEC to exist and may eventually slow down overall output. He said that 350WHP is the limit for existance of VTEC...he's saying that his friend's T88 turboed B18C with 8.8 CR had taken out VTEC because at that compression rate, VTEC is uselss. Can anyone comfirm on this? Because as far as I'm concern, VTEC has nothing to do with Turbo as they have totally separate mechanism, why would VTEC be in the way of big turbo is what I don't get.
I think Steven Papadakis's Civic runs T88 H22A engine, he said that car would not have VTEC as well as the infamous Top Fuel Type-RR S2000/EK9.
His another point of view is that B series engine has short valve stroke distance, and thus not efficient for Turbo. I said that the distance can be altered by changing valves. What's the real deal?
Obviously, I have no clue on Turbo+VTEC setups. So I need yall help and inputs on the theory of such setup. TIA.
06-05-2006, 10:47 PM
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Re: How Long Can Turbo and VTEC co-exist together? (nEoMuGen)
your friend is full of **** and doesnt know what hes talking about. a t88 on a b series? Check all the dyno graphs of people gaining power on a vtec head. And a bigger turbo lowering compression, W...T...F?
Modified by 95GSRTT at 8:22 AM 6/6/2006
Modified by 95GSRTT at 8:22 AM 6/6/2006
06-05-2006, 11:05 PM
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Re: How Long Can Turbo and VTEC co-exist together? (95GSRTT)
Can you show me some link to these dyno chart with comparison of VTEC head and non-VTEC head?
I think what he meant was, that for bigger turbo, one would disengage the engagement between lower and higher cam.
I think what he meant was, that for bigger turbo, one would disengage the engagement between lower and higher cam.
06-06-2006, 10:37 AM
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Re: How Long Can Turbo and VTEC co-exist together? (aallbbeerrtttttt)
How many LS head turbo motors has ur boy seen that make good power? 
dont listen to ur friend...
dont listen to ur friend...
06-06-2006, 10:50 AM
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Re: How Long Can Turbo and VTEC co-exist together? (Red Bull)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Red Bull »</TD></TR><TR><TD CLASS="quote">How many LS head turbo motors has ur boy seen that make good power? don't listen to ur friend...</TD></TR></TABLE>
maybe you should look at my thread that has over 200 pages with many 300+ LS turbos!
about the whole Vtec thing... people need to understand that "vtec" is the "TRANSITION" to a higher profile cam that is all it does. it gives the motor the ability to run 2 different profiles to optimize its power potenial!
older motor when you throw in a cam/cams you had something to thing about if u wanted top end power you were going to be **** out of luck down low, if u wanted low end top end was suckin!
but with vtec, vvti, and all the others you can have a bit of both worlds!
in racing like drag you don't need anything below 5K so really you are using "VTEC" and i say vtec as the transition since it will be in the RPM range that the VTEC will engage in.
don't listen to ur friend...</TD></TR></TABLE>maybe you should look at my thread that has over 200 pages with many 300+ LS turbos!
about the whole Vtec thing... people need to understand that "vtec" is the "TRANSITION" to a higher profile cam that is all it does. it gives the motor the ability to run 2 different profiles to optimize its power potenial!
older motor when you throw in a cam/cams you had something to thing about if u wanted top end power you were going to be **** out of luck down low, if u wanted low end top end was suckin!
but with vtec, vvti, and all the others you can have a bit of both worlds!
in racing like drag you don't need anything below 5K so really you are using "VTEC" and i say vtec as the transition since it will be in the RPM range that the VTEC will engage in.
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06-06-2006, 10:51 AM
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Re: How Long Can Turbo and VTEC co-exist together? (nEoMuGen)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nEoMuGen »</TD></TR><TR><TD CLASS="quote">Can you show me some link to these dyno chart with comparison of VTEC head and non-VTEC head?
I think what he meant was, that for bigger turbo, one would disengage the engagement between lower and higher cam.</TD></TR></TABLE>
http://forums.evans-tuning.com...=3084
GT30R @ 25 psi on an LS makes 460 WHP
http://forums.evans-tuning.com...=2330
GT30R @ 15 psi on PUMP GAS on a VTEC motor makes 450 WHP
You can go ahead and let your friend know he has no clue how an internal combustion motor works, and should refrain from talking from now on. Bigger cams make more power, period. When you crossover to VTEC it isn't a crossover to some magical other engine, it's swapping to cams with more duration and more lift, which will make more horsepower end of story.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nEoMuGen »</TD></TR><TR><TD CLASS="quote">His another point of view is that B series engine has short valve stroke distance, and thus not efficient for Turbo. I said that the distance can be altered by changing valves. What's the real deal?</TD></TR></TABLE>
I don't know what the hell he's talking about, but B-series and K-series motors are some of the most potent 4-cylinder power plants on earth. There's what, a dozen cars on here into the 9's. Fastest 4-cylinder street car on earth runs a Honda K-series motor and traps 167 MPH!, and there are several gasoline running B-series motors on here and in general making over 800 WHP. 4+ horsepower per cubic inch is a pretty good turbo motor, if you ask me.
I think what he meant was, that for bigger turbo, one would disengage the engagement between lower and higher cam.</TD></TR></TABLE>
http://forums.evans-tuning.com...=3084
GT30R @ 25 psi on an LS makes 460 WHP
http://forums.evans-tuning.com...=2330
GT30R @ 15 psi on PUMP GAS on a VTEC motor makes 450 WHP
You can go ahead and let your friend know he has no clue how an internal combustion motor works, and should refrain from talking from now on. Bigger cams make more power, period. When you crossover to VTEC it isn't a crossover to some magical other engine, it's swapping to cams with more duration and more lift, which will make more horsepower end of story.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nEoMuGen »</TD></TR><TR><TD CLASS="quote">His another point of view is that B series engine has short valve stroke distance, and thus not efficient for Turbo. I said that the distance can be altered by changing valves. What's the real deal?</TD></TR></TABLE>
I don't know what the hell he's talking about, but B-series and K-series motors are some of the most potent 4-cylinder power plants on earth. There's what, a dozen cars on here into the 9's. Fastest 4-cylinder street car on earth runs a Honda K-series motor and traps 167 MPH!, and there are several gasoline running B-series motors on here and in general making over 800 WHP. 4+ horsepower per cubic inch is a pretty good turbo motor, if you ask me.
06-06-2006, 11:04 AM
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Re: How Long Can Turbo and VTEC co-exist together? (nEoMuGen)
LOL!
"Turbo lowers compression"
You should have stopped him right there, and punched him in the face for being an absolute idiot.
"Turbo lowers compression"
You should have stopped him right there, and punched him in the face for being an absolute idiot.
06-06-2006, 11:38 AM
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Re: How Long Can Turbo and VTEC co-exist together? (FR-MOB: SnoFlake)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by FR-MOB: SnoFlake »</TD></TR><TR><TD CLASS="quote">
maybe you should look at my thread that has over 200 pages with many 300+ LS turbos!
</TD></TR></TABLE>
300+ isnt sayin anything dude. Compared to a Vtec head and those numbers are garbage.
maybe you should look at my thread that has over 200 pages with many 300+ LS turbos!
</TD></TR></TABLE>
300+ isnt sayin anything dude. Compared to a Vtec head and those numbers are garbage.
06-06-2006, 11:41 AM
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Re: How Long Can Turbo and VTEC co-exist together? (Red Bull)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Red Bull »</TD></TR><TR><TD CLASS="quote">
300+ isnt sayin anything dude. Compared to a Vtec head and those numbers are garbage. </TD></TR></TABLE>
ok what about teh 400whp set ups??
#'s dont mean anything.... you can run low 11's on a LS set up on pump really easy and a lot cheaper then a vtec set up...
also you have to remember that the LS will always yield more torque then its vtec counterpart at teh same PSI....
"TORQUE IS WHAT MOVES THE MASS'S"
300+ isnt sayin anything dude. Compared to a Vtec head and those numbers are garbage. </TD></TR></TABLE>
ok what about teh 400whp set ups??
#'s dont mean anything.... you can run low 11's on a LS set up on pump really easy and a lot cheaper then a vtec set up...
also you have to remember that the LS will always yield more torque then its vtec counterpart at teh same PSI....
"TORQUE IS WHAT MOVES THE MASS'S"
06-06-2006, 11:46 AM
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Re: How Long Can Turbo and VTEC co-exist together? (FR-MOB: SnoFlake)
OMG i give up u win! U can have ur LS motors, ill stick to good ol Vtec...
Modified by Red Bull at 4:37 PM 6/6/2006
Modified by Red Bull at 4:37 PM 6/6/2006
06-06-2006, 11:49 AM
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Re: How Long Can Turbo and VTEC co-exist together? (FR-MOB: SnoFlake)
but do you know why it will make more torque? and please dont say its the extra displacement lol. Is it REALLY vtec that makes our cars make more power than an LS? Absolutely not, its the way the head was designed for the cams. Most of us already know how vtec works and its not magical. But its more expensive and much harder to make the power straight LS vs is vtec counterpart.
06-06-2006, 11:56 AM
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ls...have a longer stroke....hence more tq...but they lack high revvin....
if ur talking about racin....wouldn't it be better to make power sooner and longer in each gear
is that why a 300whp honda bseries....can tear apart a 500-600whp mustang or lamer car like that
and geez a t-88....that's called a dyno queen
who cares if it make 800-900whp...if it's only for like 1k up top
just my .02's
if ur talking about racin....wouldn't it be better to make power sooner and longer in each gear
is that why a 300whp honda bseries....can tear apart a 500-600whp mustang or lamer car like that
and geez a t-88....that's called a dyno queen
who cares if it make 800-900whp...if it's only for like 1k up top
just my .02's
06-06-2006, 11:57 AM
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Re: How Long Can Turbo and VTEC co-exist together? (FR-MOB: SnoFlake)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by FR-MOB: SnoFlake »</TD></TR><TR><TD CLASS="quote">
ok what about teh 400whp set ups??
#'s dont mean anything.... you can run low 11's on a LS set up on pump really easy and a lot cheaper then a vtec set up...
also you have to remember that the LS will always yield more torque then its vtec counterpart at teh same PSI....
"TORQUE IS WHAT MOVES THE MASS'S"</TD></TR></TABLE>
You can use gearing to trade off RPM's for torque and make any small advantage in low end torque an LS might make a non-issue, since you can't gear the motor as tightly because of the lower rev limits.
I had an EG hatch with an 81.5/87.2 motor fed by a PT67 P-trim that made 450 WHP but not even 300 WTQ on pump gas, and at 2500 pounds it still went 11.5's @ 133, it's all about gearing. LS heads are fine, but to say you'll take 10-15 ft-lbs of torque to try and make a car faster on pump gas is a little bit out there.
My heavy mustang "only" made 880 RWTQ on "low" boost when we had a dyno day last week, but it's still a lot faster than my buddy running twin T3/TO4E's with nitrous who made over 1000 RWTQ because of gearing and a top end horsepower advantage.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lucidvtec »</TD></TR><TR><TD CLASS="quote">is that why a 300whp honda bseries....can tear apart a 500-600whp mustang or lamer car like that</TD></TR></TABLE>
PS, you're going to need about 450 WHP in an EG hatch to hang with a 600 RWHP fox body.
ok what about teh 400whp set ups??
#'s dont mean anything.... you can run low 11's on a LS set up on pump really easy and a lot cheaper then a vtec set up...
also you have to remember that the LS will always yield more torque then its vtec counterpart at teh same PSI....
"TORQUE IS WHAT MOVES THE MASS'S"</TD></TR></TABLE>
You can use gearing to trade off RPM's for torque and make any small advantage in low end torque an LS might make a non-issue, since you can't gear the motor as tightly because of the lower rev limits.
I had an EG hatch with an 81.5/87.2 motor fed by a PT67 P-trim that made 450 WHP but not even 300 WTQ on pump gas, and at 2500 pounds it still went 11.5's @ 133, it's all about gearing. LS heads are fine, but to say you'll take 10-15 ft-lbs of torque to try and make a car faster on pump gas is a little bit out there.
My heavy mustang "only" made 880 RWTQ on "low" boost when we had a dyno day last week, but it's still a lot faster than my buddy running twin T3/TO4E's with nitrous who made over 1000 RWTQ because of gearing and a top end horsepower advantage.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by lucidvtec »</TD></TR><TR><TD CLASS="quote">is that why a 300whp honda bseries....can tear apart a 500-600whp mustang or lamer car like that</TD></TR></TABLE>
PS, you're going to need about 450 WHP in an EG hatch to hang with a 600 RWHP fox body.
06-06-2006, 03:15 PM
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Re: How Long Can Turbo and VTEC co-exist together? (boosted92)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted92 »</TD></TR><TR><TD CLASS="quote">
You can use gearing to trade off RPM's for torque and make any small advantage in low end torque an LS might make a non-issue, since you can't gear the motor as tightly because of the lower rev limits.
I had an EG hatch with an 81.5/87.2 motor fed by a PT67 P-trim that made 450 WHP but not even 300 WTQ on pump gas, and at 2500 pounds it still went 11.5's @ 133, it's all about gearing. LS heads are fine, but to say you'll take 10-15 ft-lbs of torque to try and make a car faster on pump gas is a little bit out there.
My heavy mustang "only" made 880 RWTQ on "low" boost when we had a dyno day last week, but it's still a lot faster than my buddy running twin T3/TO4E's with nitrous who made over 1000 RWTQ because of gearing and a top end horsepower advantage.
PS, you're going to need about 450 WHP in an EG hatch to hang with a 600 RWHP fox body.</TD></TR></TABLE>
i guess you dont get the point of what i am saying.... i am not doubting or questioning a Vtec head.. YES it is a BETTER head,
im talking about this guy ......
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Red Bull »</TD></TR><TR><TD CLASS="quote">How many LS head turbo motors has ur boy seen that make good power? dont listen to ur friend...</TD></TR></TABLE>
You can use gearing to trade off RPM's for torque and make any small advantage in low end torque an LS might make a non-issue, since you can't gear the motor as tightly because of the lower rev limits.
I had an EG hatch with an 81.5/87.2 motor fed by a PT67 P-trim that made 450 WHP but not even 300 WTQ on pump gas, and at 2500 pounds it still went 11.5's @ 133, it's all about gearing. LS heads are fine, but to say you'll take 10-15 ft-lbs of torque to try and make a car faster on pump gas is a little bit out there.
My heavy mustang "only" made 880 RWTQ on "low" boost when we had a dyno day last week, but it's still a lot faster than my buddy running twin T3/TO4E's with nitrous who made over 1000 RWTQ because of gearing and a top end horsepower advantage.
PS, you're going to need about 450 WHP in an EG hatch to hang with a 600 RWHP fox body.</TD></TR></TABLE>
i guess you dont get the point of what i am saying.... i am not doubting or questioning a Vtec head.. YES it is a BETTER head,
im talking about this guy ......
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Red Bull »</TD></TR><TR><TD CLASS="quote">How many LS head turbo motors has ur boy seen that make good power? dont listen to ur friend...</TD></TR></TABLE>
06-06-2006, 04:11 PM
#18
Re: (teamsoy1320)
The bigger the turbo the more useless your car becomes for going fast....classic! 
Here's a graph of non-vtec vs. vtec on my car. Judging by the graphs, can you tell that I loooooove vtec? 
FYI: The little spike at 5800rpm is vtec engaging...I hadn't fully adjusted it yet to smooth it out at that point, but you get the idea.
Here's a graph of non-vtec vs. vtec on my car. Judging by the graphs, can you tell that I loooooove vtec? FYI: The little spike at 5800rpm is vtec engaging...I hadn't fully adjusted it yet to smooth it out at that point, but you get the idea.
06-06-2006, 04:47 PM
#19
Re: (AF-P Dunc)
i cant believe your friend said turbo lowers the compression..just think about it for a minute,,cramming extra air into your cylinders..is it going to raise the compression or lower it under boost?? just think about it..
06-06-2006, 06:53 PM
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Re: (Mr.speaker)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mr.speaker »</TD></TR><TR><TD CLASS="quote">i cant believe your friend said turbo lowers the compression..just think about it for a minute,,cramming extra air into your cylinders..is it going to raise the compression or lower it under boost?? just think about it..</TD></TR></TABLE>
Guys, thanks all for your inputs. He pretty much went silent now, I don't really want to argue anymore and just keep throwing him VTEC+Turbo cars and dyno graphs...and ask him to explain why these contradict his points.
For compression ratio, he meant that Honda engines tend to have high compression, and in order to add Turbo, the engine have to lower the compression. This I agree....but then he goes on saying that when compression is that low, VTEC would be useless.
Anyway, he won slap-me points for:
1. Lowering compression, VTEC will not be effective
2. When a big turbo is spooling to it's max output, VTEC engagement will disable it.
3. VTEC and Turbo can only co-exist under 350WHP, anything higher, there should not be any VTEC crossover.
4. He also said that lighten flywheel gave him 15whp and made him faster on 1/4mile.
Guys, thanks all for your inputs. He pretty much went silent now, I don't really want to argue anymore and just keep throwing him VTEC+Turbo cars and dyno graphs...and ask him to explain why these contradict his points.
For compression ratio, he meant that Honda engines tend to have high compression, and in order to add Turbo, the engine have to lower the compression. This I agree....but then he goes on saying that when compression is that low, VTEC would be useless.
Anyway, he won slap-me points for:
1. Lowering compression, VTEC will not be effective
2. When a big turbo is spooling to it's max output, VTEC engagement will disable it.
3. VTEC and Turbo can only co-exist under 350WHP, anything higher, there should not be any VTEC crossover.
4. He also said that lighten flywheel gave him 15whp and made him faster on 1/4mile.
06-06-2006, 09:39 PM
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Re: (nEoMuGen)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nEoMuGen »</TD></TR><TR><TD CLASS="quote">
2. When a big turbo is spooling to it's max output, VTEC engagement will disable it.
3. VTEC and Turbo can only co-exist under 350WHP, anything higher, there should not be any VTEC crossover.
</TD></TR></TABLE>
Your friend is a complete weiner. For what techincal reason would a turbo be past its effecency rate @350whp just do to vtec aside from the turbo itself being maxed out.
Tell your friend to goto howstuffworks.com and read up on turbos and vtec, then if he still makes ignorant comments about ****, make sure to kill his parents for making such a stupid child.
2. When a big turbo is spooling to it's max output, VTEC engagement will disable it.
3. VTEC and Turbo can only co-exist under 350WHP, anything higher, there should not be any VTEC crossover.
</TD></TR></TABLE>
Your friend is a complete weiner. For what techincal reason would a turbo be past its effecency rate @350whp just do to vtec aside from the turbo itself being maxed out.
Tell your friend to goto howstuffworks.com and read up on turbos and vtec, then if he still makes ignorant comments about ****, make sure to kill his parents for making such a stupid child.
06-07-2006, 06:34 AM
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Re: (nEoMuGen)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nEoMuGen »</TD></TR><TR><TD CLASS="quote">
Anyway, he won slap-me points for:
1. Lowering compression, VTEC will not be effective
2. When a big turbo is spooling to it's max output, VTEC engagement will disable it.
3. VTEC and Turbo can only co-exist under 350WHP, anything higher, there should not be any VTEC crossover.
</TD></TR></TABLE>
1. If lowering compression would render "VTEC" useless, then quite frankly, putting a set of HKS cams into a low compression Supra motor would also be useless, right? VTEC allows the use of two cam profiles, and that's all it does. A certain cam grind would let the engine breathe well between a certain RPM band (based on cylinder head), and VTEC gives it two cam grinds to allow good breathing over a wider RPM range. Wider is better...
2. He is referring to tuning issues often related to VTEC engagement. There are cases which VTEC causes the engine to bog and lose boost during the transition. A half-competent tuner would be able to play around with fuel and timing and be able to get rid most of the problems during VTEC engagement. A more experienced tuner would know how to dial in the cam timing (if equipped with adj gears) and be able to fully make use of VTEC to flatten out the torque curve and actually let the turbo spool up sooner. This is rarely an issue with stock cams, and at most, ITR/CTR cams would sometimes have this problem depending on setup.
3. VTEC has nothing to do with how much power the engine is pushing. This is commonly mistakened with the benefits of "keeping things simple" because a 350+ WHP Honda usually needs a decent sized turbo to push those numbers. In most cases, a SC61, or a T3/T67, etc... the turbo wouldn't hit hard until 5500+ RPM, and quite frankly, that is already beyond VTEC engagement point. So in a way, it is better to disable VTEC to prevent any additional tuning issues. Would there be a performance gain by disabling VTEC? Not really because the low RPM cam profile would provide stock-like idle, smoother low RPM operation and more low-end torque off idle.
Anyway, he won slap-me points for:
1. Lowering compression, VTEC will not be effective
2. When a big turbo is spooling to it's max output, VTEC engagement will disable it.
3. VTEC and Turbo can only co-exist under 350WHP, anything higher, there should not be any VTEC crossover.
</TD></TR></TABLE>
1. If lowering compression would render "VTEC" useless, then quite frankly, putting a set of HKS cams into a low compression Supra motor would also be useless, right? VTEC allows the use of two cam profiles, and that's all it does. A certain cam grind would let the engine breathe well between a certain RPM band (based on cylinder head), and VTEC gives it two cam grinds to allow good breathing over a wider RPM range. Wider is better...
2. He is referring to tuning issues often related to VTEC engagement. There are cases which VTEC causes the engine to bog and lose boost during the transition. A half-competent tuner would be able to play around with fuel and timing and be able to get rid most of the problems during VTEC engagement. A more experienced tuner would know how to dial in the cam timing (if equipped with adj gears) and be able to fully make use of VTEC to flatten out the torque curve and actually let the turbo spool up sooner. This is rarely an issue with stock cams, and at most, ITR/CTR cams would sometimes have this problem depending on setup.
3. VTEC has nothing to do with how much power the engine is pushing. This is commonly mistakened with the benefits of "keeping things simple" because a 350+ WHP Honda usually needs a decent sized turbo to push those numbers. In most cases, a SC61, or a T3/T67, etc... the turbo wouldn't hit hard until 5500+ RPM, and quite frankly, that is already beyond VTEC engagement point. So in a way, it is better to disable VTEC to prevent any additional tuning issues. Would there be a performance gain by disabling VTEC? Not really because the low RPM cam profile would provide stock-like idle, smoother low RPM operation and more low-end torque off idle.
