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spetz
08-02-2005, 05:16 AM
Are there any issues with overlap or too high of a lift on these VTEC's when turbo'ing them?

Or any other issues with high compression or weak internals?

wynode
08-02-2005, 07:40 AM
IT all depends on how much boost you want to run and an which engine. More info please :)

bennjamin
08-02-2005, 10:52 AM
reserch issues more so , with compression reducing when using a tubo charger on a vtec powered car...

ProECU
08-02-2005, 12:08 PM
for forks sake, offer the guy some help...

Issues as I see them are:

Compression ratio. Static compression means jack! its the dynamic compression you need to worry about. You can bleed compression with more overlap, hence the use of cam gears are good here.

Thicker head gasket..... waste of time, might allow more boost, but ask yourself why!
Is it more pressure that makes power or the quality of combustion?

These issues are particular to your setup, b16's typically like more overlap (scavenging), to draw in the charge at lower piston speeds (b16s have long rods) as an example.

just boost the damn thing, you'l love it.

DLO01
08-02-2005, 12:23 PM
Are there any issues with overlap or too high of a lift on these VTEC's when turbo'ing them?

Or any other issues with high compression or weak internals?
I think the issue is more to do with overlap with the Hi Cam when at the end of the exhaust stroke both Exhaust and Inlet valves are open, this good with NA cars as exiting exhaust fumes draw in air/fuel for the next intake stroke.

With Turbo Vtec's I don't think there is a problem with pressurised air blowing straight through both intake and out the exhaust valves when the overlap exists (correct me if I am wrong) Because the Hi Cam only comes in to play at high rpm, therefore I don't think there is enough time for both Intake and exhaust valves to be open for the pressurised air/fuel to blow through. Again I am not sure so any other theory's would be appreciated.

With regard to standard engine internals etc. Honda make a strong motor as standard. With a proper Turbo setup and tuning there should be no problems. I am running 9psi on my B16A2 with standard internals.

Hope this helps in some way. :D

poid
08-02-2005, 05:04 PM
generally there arent any issues with overlap, not sure if that will be the case with your MIVEC though spetz. Also the internals are normally strong enough for 8-12psi depending on the engine. No need to decompress either.

JR Performance
08-02-2005, 06:58 PM
Like everyone says, boost the bugger, 12psi and you will love it and make sure you get it tuned by someone who has done it before and you should be fine.

spetz
10-02-2005, 10:51 AM
I want to turbo it...
But I put the FTO MIVEC engine into a lancer so I can stay NA

I want to slay some cars on the road and leave them shocked that I don't have boost.

But... it seems like staying NA is bucket loads of money for small gains.

BTW. Sorry guys for using Honda forums but no one knows anything about MIVEC and it's kinda the same thing so... :)

poid
10-02-2005, 06:32 PM
well what you are saying is correct, to get the same gains from NA mods is gonna cost you a crapload of money if its even possible to do in this country (as you say the amount of MIVEC expertise here isnt great).

Quite simply, i dont think you could go wrong with, say, a GT28R at 6psi

creativepunka
10-02-2005, 06:47 PM
well we just done a turbo set up on my mates mivec lancer. he strrated off with the na setup and got 130fwhp (we could rev the thing to 10grand on a microtec). he decided to turbo it and used a gsr lancer exhaust manifold and turbo and a haltec cause he didnt like the microtec. the problem about the mivec is the huge compression. we put a 2.2mm head gasket and had the boost at 15psi because we couldnt get it lower, we also have a big front mount and the thing was so quick for about a week till we blew the headgasket. lol its got a new head gasket and getting tuned now. u want the four banga ai?

PhatSol
11-02-2005, 11:07 AM
well we just done a turbo set up on my mates mivec lancer. he strrated off with the na setup and got 130fwhp (we could rev the thing to 10grand on a microtec). he decided to turbo it and used a gsr lancer exhaust manifold and turbo and a haltec cause he didnt like the microtec. the problem about the mivec is the huge compression. we put a 2.2mm head gasket and had the boost at 15psi because we couldnt get it lower, we also have a big front mount and the thing was so quick for about a week till we blew the headgasket. lol its got a new head gasket and getting tuned now. u want the four banga ai?

Thats a 4G92 MIVEC, Spetz is running the 6A12 MIVEC motor. The 4G92 shares the same exhaust manifold patten as the GSR motor (4G93t) and actually has some room left in the engine bay. The 6A12 barley clears the firewall and radiator.... It's a bit like the H22 of lancers except V6 :D

Weq
11-02-2005, 11:52 AM
Actually my SOHC loves high lift that my stage2 cam brings. There are some nice articles out there on overlap,l and it seems the old ways of thinking dont really apply these days to our hi-po vtec's.

spetz
12-02-2005, 11:11 AM
Yeah 4G92 MIVEC... so different.. it's obviously in an old lancer too to fit GSR turbo stuff on it. as it would not fit on mine due to engine/gearbox rotation.
They run 11.5:1 CR
Mine is only 10:1 so I am in an already better base.
And 15psi on a 4G92 MIVEC is overkill.


Out of curiousity, how quick is quick? And how was traction? Bloody FWD... ;)


PS. As for aftermarket on the 6A12 it is existant. You just need to know where to look. I am in Cyprus now (they love MIVEC and VTEC here, more so than turbo) and a lot of shops told me HKS and JUN made parts for the FTO.
Also RPW in Oz (www.rpw.com.au) makes everything you can think of for the MIVEC's

creativepunka
12-02-2005, 11:51 AM
we havnt had a run yet but we could spin the fronts in fourth gear kinda easly. we have to get te thing tuned first.

bigjo5
14-02-2005, 01:07 PM
whats overlap?

DLO01
14-02-2005, 01:13 PM
whats overlap?

I think the issue is more to do with overlap with the Hi Cam when at the end of the exhaust stroke both Exhaust and Inlet valves are open, this good with NA cars as exiting exhaust fumes draw in air/fuel for the next intake stroke.

Its where the Intake and Exhaust valves are open at the same time. :D

bigjo5
14-02-2005, 01:16 PM
oh i see. thanks

bigjo5
14-02-2005, 01:17 PM
so is overlap a good or a bad thing?

joyride
16-02-2005, 11:20 AM
this site would help you with everything u need to know about cars.
www.howstuffworks.com

TODA AU
19-02-2005, 03:15 AM
Theory~shmery...
Don't think, just believe...

Fact...
Vtec + turbo works really well.
Type R Vtec + turbo works even better.
TODA Spec B Vtec + turbo works better again.
All out set-ups use Spec C's.

The only time overlap is an issue is when the turbo is too small.
Size your turbo as you would for a 2L engine if you have a B16A.
IE: 370~450hp size range.
Good examples to use. TRUST T518Z, HKS 2835, GTBB400 etc etc.
Don't use old T3/T4 crap & stay away from 2nd hand junk.
Do it once, do it right.

2 examples...
B16A, std internals + de-comp plate.
HKS 3037, Type R cams & springs.
Boost threashold 2800rpm (wastegate opens at 3000rpm - ie max boost)
Max rpm 8800rpm. Power output 180kw @ front wheels. (16psi)
Std pistons, Std rods... Apexi Power FC ECU (AP engineering)
550cc/min injectors, std ignition system, walbro fuel pump, std fuel regulator.
No reliability issues.

B16A + ported head + Forged pistons + rods + Spec B's etc
GCG 450hp turbo. (3037S turbo core)
Boost threashold 3200rpm. (wastgate opens 3500rpm - Ie: max boost)
Max rpm 9000. Power output 270kw @ front wheels (20psi)
Again, no problems with reliability or driveability.
Microtech MTX8 ECU, 550cc/min injectors, 044 fuel pump, adjustable fuel reg,
CDI + external coil. 1/4mile ET 12.2 @ 122mph (Street tyres - drag combat)

I can site more examples too...
Don't fuss too much over the theory if you can't do it yourself...
Just spend some time finding someone who can.

9krpm
19-02-2005, 08:23 AM
what cam do you recommend for a turbo s2k toda au?
Has Elias dyno his car with the new cam yet?

ProECU
20-02-2005, 06:28 PM
B16A, std internals + de-comp plate.
HKS 3037, Type R cams & springs.
Boost threashold 2800rpm (wastegate opens at 3000rpm - ie max boost)
Max rpm 8800rpm. Power output 180kw @ front wheels. (16psi)
Std pistons, Std rods... Apexi Power FC ECU (AP engineering)
550cc/min injectors, std ignition system, walbro fuel pump, std fuel regulator.
No reliability issues.


180kW at 16psi is a mule in my opinion

WPN.22R
20-02-2005, 08:51 PM
and also....

H22a standard internals and GT30/40 is the bomb Yo.. easy 200kw atw

H22a with GT30/40 and built bottom end (sleeves-pistons-rods) 250kw atw

H22a with GT30/40 built bottom end and skunk2 top end and bigger intake manifold ......


ill get back to you shortly;)

smoknhothonda
21-02-2005, 01:29 PM
H22a with GT30/40 built bottom end and skunk2 top end and bigger intake manifold ......


ill get back to you shortly;)[/QUOTE]

I would be interested to know how much extra power the Skunk 2 intake manifold makes. Do you have a Skunk 2 throttle body also?

I have noticed they are making these for the F series Accords, and IMO wouldnt be a bad mod for when I eventually boost my F22B1 (I can make extra power atm N/A, and even more boosted)

Who is tuning your ride man?! Sounds freakn wild, and the plate definately backs da shit up!

Cheers

WPN.22R
22-02-2005, 06:47 PM
dyno dave is doin the work for me... cant wait to get it all together! the intake standard is 60mm the skunk2 is 65mm so volume wise there will be a difference for sure.. (a lot more air )

its been a long project on and off.. but this is probably the last i will do engine wise.

TODA AU
28-02-2005, 05:29 AM
what cam do you recommend for a turbo s2k toda au?
Has Elias dyno his car with the new cam yet?

Spec B's...

Don't know about Elias.

Sp3rMz
14-03-2005, 03:34 AM
Theory~shmery...
Don't think, just believe...

Fact...
Vtec + turbo works really well.
Type R Vtec + turbo works even better.
TODA Spec B Vtec + turbo works better again.
All out set-ups use Spec C's.

The only time overlap is an issue is when the turbo is too small.
Size your turbo as you would for a 2L engine if you have a B16A.
IE: 370~450hp size range.
Good examples to use. TRUST T518Z, HKS 2835, GTBB400 etc etc.
Don't use old T3/T4 crap & stay away from 2nd hand junk.
Do it once, do it right.

2 examples...
B16A, std internals + de-comp plate.
HKS 3037, Type R cams & springs.
Boost threashold 2800rpm (wastegate opens at 3000rpm - ie max boost)
Max rpm 8800rpm. Power output 180kw @ front wheels. (16psi)
Std pistons, Std rods... Apexi Power FC ECU (AP engineering)
550cc/min injectors, std ignition system, walbro fuel pump, std fuel regulator.
No reliability issues.

B16A + ported head + Forged pistons + rods + Spec B's etc
GCG 450hp turbo. (3037S turbo core)
Boost threashold 3200rpm. (wastgate opens 3500rpm - Ie: max boost)
Max rpm 9000. Power output 270kw @ front wheels (20psi)
Again, no problems with reliability or driveability.
Microtech MTX8 ECU, 550cc/min injectors, 044 fuel pump, adjustable fuel reg,
CDI + external coil. 1/4mile ET 12.2 @ 122mph (Street tyres - drag combat)

I can site more examples too...
Don't fuss too much over the theory if you can't do it yourself...
Just spend some time finding someone who can.

Are you saying don't use TODA C plus turbos? I've been considering boosting my type R with lil t28 t25 + my toda Cs? Or is that big no no?

TODA AU
14-03-2005, 06:16 AM
Are you saying don't use TODA C plus turbos? I've been considering boosting my type R with lil t28 t25 + my toda Cs? Or is that big no no?

TODA C's + turbo only work in some instances. Combination is everything.
The turbo must be big enough & the compression must be up also.
In any case, this is for a maximum effort turbo set-up.
In your case, you'll need to start with a bigger turbo.

Regarding Spec C's & turbo's.
Though it is something you guys are aware of these days because James (Hondata) talks it up as though he was the one who discovered it.
The fact that he was told how to do it seems to have been forgotten.

[DC2]
21-04-2005, 10:04 PM
juss keep on 12 pounds wtih stock internals