vr6 turbo build info

[cicciovr6 0]

Hi.. i'm looking to start a turbo project for my vr6 12V

So i have some questions for you: 

With stock internals and a head spacer what is the max boost?

What range of hp stock pistons/rods can handle?

 

[RBPE 198]

Tuning, and by that I mean proper tuning, is nothing like "what hp can x do", the reason is science. What can damage such parts is shearing and twisting forces;

https://en.wikipedia.org/wiki/Shear_strength

https://en.wikipedia.org/wiki/Torsion_(mechanics)

Question is - what causes such excess stresses? If you're gong from an NA VR6 to an FI VRT, how do you know if your map is still running the oem knock regulation checks without looking at the data? A bad map can cause detonation and such blasts cause excess stress which cause high shearing and twisting forces - ergo damage! What if the bolts were not torqued correctly and as such, lifting the head causes damage etc........ 

In order to give you a answer then, 700hp or so has bee had, I think, by Lugnuts on stock rods/pistons, many factors to consider though! I think 400-450hp is well proven with ARP hardware like rod bolts and head studs with only a spacer but as said, it's the links above that kill your engine!

Hop that clarify's things as "what hp" may lead to big holes in your pocket! 

I think we need a bit of a FAQ thread for the tuning fundamentals no?

Edited March 28, 2016 by RBPE
My kyboard is pants! x 3

[cicciovr6 0]

I'm agree with you. But i think there is a safe limit for max boost for example

With a ARP hardware what is the max bost for a vr6t?

[RBPE 198]

The volume of air can change with things like the size of the turbo don't forget! However, 18-20psi seems to be the limit people push to before forged internals on something like a GT35R with ARP/spacer , can push higher but lot's to do right for that.

Also - what compression ratio for the spacer, they range from 7:1 to 10:1? That determines a lot - 9.0:1 compression ratio or 8.5 for above, both can do 18+

[cicciovr6 0]

So for a stock internals the boost limit is around 18psi with 9:1 compression ratio? Or 8,5:1 is better than 9:1 whit this boost?

[RBPE 198]

Lower compression generally gives better scope for knock suppression all things being considered equal;

https://en.wikipedia.org/wiki/Compression_ratio

Both can handle 18psi and I have seen 700hp 28psi cars running 9.0:1 pistons - as a guide, 9.0:1 with 16-18psi max - as well as good tuning throughout - seems to be a good set up that a number of owners have chosen and is what I would use as a guide with cautions as mentioned for max boost.

[cicciovr6 0]

For around 350hp which turbo is the best? 

[RBPE 198]

Info is in the turbo thread, you want to aim for something at least 500hp rated due to displacement. GTX30R or EFR7163 would likely be the best. GT30R would be a bit cheaper and then T3/04 hybrids cheaper still but can get journal or ball bearing ones.

 

Budget no option - one of the first two - 0.63ar or so on the turbine will give you quick spool but choke up top, 0.82ar good allrounder preferred by most and anything higher is probably not best for what you seem to be aiming for. So, it's a case of quick spool less top end 0.63 or good throughout the rev range 0.82 if you go that route.

[matty.vrt 120]

From my experience 576 bhp is fine on stock internals (I ran like this for 3 years). That was produced by a GT3582R .82 T3 hotside and 26psi of boost. At times I ran up to 30psi with boost spikes.

 

By stock internals i mean spacer plate only. Stock head bolts will have no problem either, I hate that everyone says that you must fit ARP hardware, save your money and get 20 head bolts for £20 at Euro car parts. I understand its a nice to have as they are re-usable but necessity they are not.

 

The gearbox is where you will have issues.

 

Standard 02a is clutch is good for 300bhp and gearbox 400bhp. But be warned you are on borrowed time at the limit.

 

Realistically an 02M conversion is the only logical way using a 2wd adapter plate.

 

Hope that helps you in your turbo quest.

 

[cicciovr6 0]

Thanks a lot for those fantastic info!!!!

So the limit is gearbox and clutch..

So the safe mode is to run 350hp

I ask you some other info:

Which head spacer?what compression ratio??

Which head gasket?

Is ok gt3882r for 350hp or is it too much bigger? Or gt3076 is the best way to get 350hp?

[matty.vrt 120]

3 hours ago, cicciovr6 said:

Thanks a lot for those fantastic info!!!!

So the limit is gearbox and clutch..

So the safe mode is to run 350hp

I ask you some other info:

Which head spacer?what compression ratio??

Which head gasket?

Is ok gt3882r for 350hp or is it too much bigger? Or gt3076 is the best way to get 350hp?

Gt3582r Is a good turbo your application and my number 1 choice if it's in your budget. Garretts T61 is also a good option if your on a budget and can't afford ball bearing.

 

I have ran GT35 from 7psi making 298bhp all the way to 26psi running 576bhp. Trust me when you get the turbo bug you will be happy you picked a turbo with plenty of head room because addictive does not even cover it.

 

Another area not to skimp is Wastegate. That is the only component between requested boost and unlimited (well to a point but you get what I mean).

[ssaunders 199]

40 minutes ago, matty.vrt said:

Gt3582r Is a good turbo your application and my number 1 choice if it's in your budget. Garretts T61 is also a good option if your on a budget and can't afford ball bearing.

 

I have ran GT35 from 7psi making 298bhp all the way to 26psi running 576bhp. Trust me when you get the turbo bug you will be happy you picked a turbo with plenty of head room because addictive does not even cover it.

 

Another area not to skimp is Wastegate. That is the only component between requested boost and unlimited (well to a point but you get what I mean).

You can never have enough of BOOST!

[bennyk 1,238]

You can never have enough of BOOST!

That's not what your gearbox said!

[ssaunders 199]

4 hours ago, cicciovr6 said:

Thanks a lot for those fantastic info!!!!

So the limit is gearbox and clutch..

So the safe mode is to run 350hp

I ask you some other info:

Which head spacer?what compression ratio??

Which head gasket?

Is ok gt3882r for 350hp or is it too much bigger? Or gt3076 is the best way to get 350hp?

Don't take these figures for granted, not every box is equal! I ripped through a 6 speed quaife gearset only running 340! Speaking to quaife they only rate the kits to take standard power! So 174? Whatever you do it will only find the next part in the chain to break. S/C don't cause as much of an issue as they only hit maximum boost at the top end of rev range, turbos cut in fully earlier and cause extra strain on the gearbox. Personally I would not run more than 300 through a standard box and expect reliability. I am getting my replacement box till I go haldex and I am getting the diff bolts done as minimum also shot peening 2nd,3rd and 4th as I have 3 boost levels 260-280 and 340. The 02A has issues with turbo and 3rd stripping, I am only going to use the box till next year when I go haldex but better safe than sorry!

let me know how you go.

good luck

steve

[ssaunders 199]

14 minutes ago, bennyk said:

That's not what your gearbox said!

Love you BK but F u c k off! So I bought a lemon! Just call me Mr Delmonte!

[JakeP 53]

Gt3582r Is a good turbo your application and my number 1 choice if it's in your budget. Garretts T61 is also a good option if your on a budget and can't afford ball bearing.

 

I have ran GT35 from 7psi making 298bhp all the way to 26psi running 576bhp. Trust me when you get the turbo bug you will be happy you picked a turbo with plenty of head room because addictive does not even cover it.

 

Another area not to skimp is Wastegate. That is the only component between requested boost and unlimited (well to a point but you get what I mean).

What gearbox did you use with 576 bhp?

[matty.vrt 120]

DRP coded 02M