So a buddy just offered me a nearly new Holset H1C for next to nothing.

I don't know much about turbo sizes, but I am thinking of adding a single turbo to my car sometime in the future. Would this be a useable turbo for the VH? I'd be looking for somewhere around the 375-425 HP range

Turbo guru's please chime in.

Josh

mad tiny for the vh's capacity.

Even for a low boost application?

Also would be interested in suggested turbos.

I am think a GT30R would be great for 6-8 PSI

What about 2 t28's

we use a TA45 chinese copy with a 1.2 exhaust housing,last tune found it was startin to restrict on the exhaust,once motor back together we mounting a Cat turbo off a Cat C15,using a Garrett 1.4 exhaust housing,its pretty massive but it was cheap as and should be good for 400+ kw

a gt30r will be waaaaay too small for the vh, even on a 3l it maxes out around 7krpm depending on mods.
at a MIN i would not run anything less than an hx40 if you're looking at holset turbos, even the hx35 is on the small side of things for the vh.
gotta remember engine capacity has alot to do with the turbo sizing, cant just slap any old turbo set on there and it expect it to be good.
when i looked into turboing a vh i decided that the 'small' garrett gt42 would be ideal as it would spool up just shy of the surge line and make power all the way to 7500...twin t28 turbos might be ok if you can find some 'big wheel' compressors...however the t28's exhaust is very limiting.

Most turbos are gonna be too small on the exhaust side for the VH. You wanna keep the back pressure down regardless of how much boost you plan on running. You're gonna want to look for something T6 frame for a single or T4 frame for twins. Think big a/r as well.

Carl H wrote:a gt30r will be waaaaay too small for the vh, even on a 3l it maxes out around 7krpm depending on mods.
at a MIN i would not run anything less than an hx40 if you're looking at holset turbos, even the hx35 is on the small side of things for the vh.
gotta remember engine capacity has alot to do with the turbo sizing, cant just slap any old turbo set on there and it expect it to be good.
when i looked into turboing a vh i decided that the 'small' garrett gt42 would be ideal as it would spool up just shy of the surge line and make power all the way to 7500...twin t28 turbos might be ok if you can find some 'big wheel' compressors...however the t28's exhaust is very limiting.

Problem with turbo-ing the VH is finding room to do it....

In a Z32 there is practically no room. I can't see a way of fitting twin T28's, there just isn't the room next to the block. Maybe front mount in the SMIC position like Nick was doing, but too many compromises for my liking. There is a bit of room on the passenger side, I've tried a HX35 and that sort of fit. It was a internal gate turbo, the external version would probably fit pretty well. But you would still have to find somewhere to fit a 50mm wastegate. I could see boost control being a issue with a 'small' turbo. I just can't see a GT42 fitting anywhere, maybe a front mount in a S13/14 or R32/33/34, but no chance in a Z32. Not if you have the radiator anywhere near the standard position anyway.

In my S13 there is plenty of room for a single in the space behind the drivers headlight. I would have to reroute some wiring and the secondary relay box, but there is room.

Just mount them up in the air above the motor, and run no bonnet

Mettler wrote:Just mount them up in the air above the motor, and run no bonnet

Typical dodgy Kiwi's

I'm in a few minds with my Zed. As it is now it is no where near powerful enough, no more than 300rwhp I would guess. Definitely needs another 200hp or so. Turbo-ing it will be a bit of a PITA but would be possible. About the biggest issue I have is getting intake to the turbo sorted, then charge air up to the plenum. It's tight as. I can't see a nice way of using a air-air intercooler, would most likely have to be water injection or a water-air. LHD Z's would have it easier as the turbo would be mounted on the opposite side to the throttle. Exhaust manifolds and dump would be easy enough either side though.

Single is definitely the way to go for space constraints. Put the turbo anywhere, run both manifolds to it, and use a single in/out intercooler.

remote mount, or rear mount.

Remote mount is the route I'm traveling this winter.

Slim did twin T28's. I believe theyre mounted on log manifolds between the block and frame rails. Or somewhere down there.

I think T3/T4 50 trim is a prefect turbo (as twins). Or if youve got the funds, twin GT30's.

Jared, I'm curious why you recommend T4's. I dont think something that size is necessary unless youre shooting for 800whp.

hannibal wrote:Slim did twin T28's. I believe theyre mounted on log manifolds between the block and frame rails. Or somewhere down there.

I think T3/T4 50 trim is a prefect turbo (as twins). Or if youve got the funds, twin GT30's.

Jared, I'm curious why you recommend T4's. I dont think something that size is necessary unless youre shooting for 800whp.

Size of the compressor dictates horsepower. The engine is big so you don't what to restrict the exhaust side and cause added back pressure. 1:1 is as good as it gets. Most big engines with small turbines will be much higher. Even if you do a smaller turbo like a 30r, still go with the larger T4 hot side and the biggest a/r available.

How about a Garrett TO4S 60-1 with a .84 AR. I'm not looking for huge horsepower. I think this would spool quickly and be good for a maximum of ~500hp.

LEMHEAD16 wrote:So a buddy just offered me a nearly new Holset H1C for next to nothing.

I don't know much about turbo sizes, but I am thinking of adding a single turbo to my car sometime in the future. Would this be a useable turbo for the VH? I'd be looking for somewhere around the 375-425 HP range

Turbo guru's please chime in.

Josh

Nonsense talks of it being too small, it comes off of a 5.9L diesel engine and it has a 450whp capability install it and use it you will have a good learning experience.

Are T28's decent for a twin set up on this engine and what would be the expected HP?

If they are not a decent choice what is recommended. I have seen several ppl say the GT30, T4, etc. Another option I thought of was the Disco Potato Twins!?! Any thoughts?

There is nothing recommended without a power goal every turbocharger makes a certain amount of HP efficiently or inefficiently.

Gt28RS can do 600rwhp on z32 300zx.

When I said GT30's, I'm referring to a GT3071R or 3076 with T3 turbine. GT28's and smaller only come with T25 exhaust housings, though I guess you can find a turbo assembler that puts a T3 housing on the GT28 (ATP, Precision, etc). I wouldnt get anything less than a T3 turbine.

A T28 will certainly work but I imagine a pair would not be able to hold 10psi til redline. This may work well for a street driven VH. But anytihng above 5500rpm is gonna be way off the comp map. I'm talking about the stock SR20 turbo aka Garrett GT2560R here.

Someone linked to a guy who built a VH45 with twin GT28's in an S15 drift car. He says he's running 0.7bar (about 10.3psi) and makes 500hp with 600lbs-ft at 3000rpm. I think those are numbers at the crank/flywheel.
http://www.driftworks.com/forum/drift-c ... o-s15.html

A T3/T4 50 trim or GT3071/3076 would make similar power at less boost (0.5bar?) and would be able to sustain that boost level past 7000rpm.

For a single turbo, I think even a T4 turbine is too small. T6 would be my guess. Look a Jeff' Taylor's huge turbo. I think its a T6 turbine from a class 5/6 diesel truck.

hannibal wrote:When I said GT30's, I'm referring to a GT3071R or 3076 with T3 turbine. GT28's and smaller only come with T25 exhaust housings, though I guess you can find a turbo assembler that puts a T3 housing on the GT28 (ATP, Precision, etc). I wouldnt get anything less than a T3 turbine.

A T28 will certainly work but I imagine a pair would not be able to hold 10psi til redline. This may work well for a street driven VH. But anytihng above 5500rpm is gonna be way off the comp map. I'm talking about the stock SR20 turbo aka Garrett GT2560R here.

Someone linked to a guy who built a VH45 with twin GT28's in an S15 drift car. He says he's running 0.7bar (about 10.3psi) and makes 500hp with 600lbs-ft at 3000rpm. I think those are numbers at the crank/flywheel.
http://www.driftworks.com/forum/drift-c ... o-s15.html

A T3/T4 50 trim or GT3071/3076 would make similar power at less boost (0.5bar?) and would be able to sustain that boost level past 7000rpm.

For a single turbo, I think even a T4 turbine is too small. T6 would be my guess. Look a Jeff' Taylor's huge turbo. I think its a T6 turbine from a class 5/6 diesel truck.

Doesn't seem that drift car is using an engine dyno to tune for horsepower, splitting 4500cc's is 2.2L.

You people are overly sizing the housing that just moves the power band up losing airflow down low.

Once again you want a power goal not a random turbo size.

There is a twin turbo kit for a mustang 4.6 since its very similar to the VH it creates 460whp @ 9 psi and will easily create 600 with a boost increase perfect VH I'd even use stock everything except for headstuds and rod bolts.

OK expert, I have a T04z ar 1.06. It is running 10psi. It has 2 psi at 2000rpm and hits 10 before 3000rpm and the boost creeps fractionally to about 10.5 by the current redline which is only 6000rpm as still on factory injectors and they are at 87% then. When the rev limit is reached the dyno graph is still basically a striaght line, boost is still constant and it has 375rwhp (at 6000 rpm without VVT switched either)
So here is a turbo spec'd for 850hp yet is providing very driveable power at under 600hp (flywheel).
So in your opinion I have an overly sized turbo that is a dog to drive. Funny that in reality it is extremely drivable with good power from 2000 rpm through to redline. It has a power band of 3500 rpm purely because I need to fit bigger injectors but can't as I've run out of money. Once it has new injectors

Power goal! What a load of crap. A power goal is for people who want to talk about how much power they have. What is impoerant is power derlivery and actual performance. My setup was spec'd with the goal of having power before 3000rpm and no restriction at 7500rpm. I argued that a turbo capable of 850hp was way too big and would give too much lag. BUT I listened to people who new far more about this stuff than I do and fitted this oversized turbo. All the books say it is too big but experience said it would work and it does. I have plenty of power and it is predictable and controlable. There is no surging, minimal lag and no restriction at the topend. (On the dyno it flew to over 7000rpm before we put limits on it)
So sure this is a competition vehicle but it is for offroad racing where power derlivery and control is far more important than outright power.

So before you start 'us guys' that we are just fitted randon turbo's, I suggest you read a few more books or actually listen to what people who have actually done it discover.

darinz wrote:OK expert, I have a T04z ar 1.06. It is running 10psi. It has 2 psi at 2000rpm and hits 10 before 3000rpm and the boost creeps fractionally to about 10.5 by the current redline which is only 6000rpm as still on factory injectors and they are at 87% then. When the rev limit is reached the dyno graph is still basically a striaght line, boost is still constant and it has 375rwhp (at 6000 rpm without VVT switched either)
So here is a turbo spec'd for 850hp yet is providing very driveable power at under 600hp (flywheel).
So in your opinion I have an overly sized turbo that is a dog to drive. Funny that in reality it is extremely drivable with good power from 2000 rpm through to redline. It has a power band of 3500 rpm purely because I need to fit bigger injectors but can't as I've run out of money. Once it has new injectors

Power goal! What a load of crap. A power goal is for people who want to talk about how much power they have. What is impoerant is power derlivery and actual performance. My setup was spec'd with the goal of having power before 3000rpm and no restriction at 7500rpm. I argued that a turbo capable of 850hp was way too big and would give too much lag. BUT I listened to people who new far more about this stuff than I do and fitted this oversized turbo. All the books say it is too big but experience said it would work and it does. I have plenty of power and it is predictable and controlable. There is no surging, minimal lag and no restriction at the topend. (On the dyno it flew to over 7000rpm before we put limits on it)
So sure this is a competition vehicle but it is for offroad racing where power derlivery and control is far more important than outright power.

So before you start 'us guys' that we are just fitted randon turbo's, I suggest you read a few more books or actually listen to what people who have actually done it discover.

Slow your role dude. The power goals are very important when deciding on the turbo size and anyone that says different is simply ignorant. That's 100% Fact.

When you take into account the power goals you can match the compressor and exhaust housing sizes and wheel trims to give you the most power within your most driven rpm band. Ease up on the attitude and explain yourself like an adult and you'll find people actually listen vs just think you're a douche bag.

WD

LEMHEAD16 wrote:So a buddy just offered me a nearly new Holset H1C for next to nothing.

I don't know much about turbo sizes, but I am thinking of adding a single turbo to my car sometime in the future. Would this be a useable turbo for the VH? I'd be looking for somewhere around the 375-425 HP range

Turbo guru's please chime in.

Josh

The issue with this turbo isn't the compressor side, the compressor will flow enough air to support 450whp. The exhaust housing however is just a T3. Even a large .83 AR T3 housing will be semi restrictive at high rpms. What you could do is use a 50mm external wastegate. This will move enough exhaust gas volume to avoid boost spikes and be able to handle the amount of exhaust volume in the high rpms.

I still wouldn't run more then 8 psi though, after that you may start to suffer from exhaust gas reversion in the upper rpms.

Just my .02

BTW, we use this turbo on the KA24DE It's slightly laggy on the KA, say full boost by 3500 rpm. So you'll have zero lag...probably be fun as hell around town.

darinz wrote:OK expert, I have a T04z ar 1.06. It is running 10psi. It has 2 psi at 2000rpm and hits 10 before 3000rpm and the boost creeps fractionally to about 10.5 by the current redline which is only 6000rpm as still on factory injectors and they are at 87% then. When the rev limit is reached the dyno graph is still basically a striaght line, boost is still constant and it has 375rwhp (at 6000 rpm without VVT switched either)
So here is a turbo spec'd for 850hp yet is providing very driveable power at under 600hp (flywheel).
So in your opinion I have an overly sized turbo that is a dog to drive. Funny that in reality it is extremely drivable with good power from 2000 rpm through to redline. It has a power band of 3500 rpm purely because I need to fit bigger injectors but can't as I've run out of money. Once it has new injectors

Power goal! What a load of crap. A power goal is for people who want to talk about how much power they have. What is impoerant is power derlivery and actual performance. My setup was spec'd with the goal of having power before 3000rpm and no restriction at 7500rpm. I argued that a turbo capable of 850hp was way too big and would give too much lag. BUT I listened to people who new far more about this stuff than I do and fitted this oversized turbo. All the books say it is too big but experience said it would work and it does. I have plenty of power and it is predictable and controlable. There is no surging, minimal lag and no restriction at the topend. (On the dyno it flew to over 7000rpm before we put limits on it)
So sure this is a competition vehicle but it is for offroad racing where power derlivery and control is far more important than outright power.

So before you start 'us guys' that we are just fitted randon turbo's, I suggest you read a few more books or actually listen to what people who have actually done it discover.

This reply is so self demeaning that I see no need in replying to that.

I havent even looked at single turbos for the VH, so I'm just guessing here. But I'm surprised that T04Z keeps up so well.

David, Ive looked for some kits for the Ford 4.6L motor. All I find are kits with "67mm" or "70mm" turbos with no mention of what frame size. Any idea what turbos they're using on this motor?

Twins are easier to pick cause you just start looking at what SR20s and KA-Ts use...

Most consider anything smaller then a T4 far to constrictive for the 4.6 or bigger in singular form. You could in fact run 2 HC1's if you had tons of room and didn't mind a little lag.

If mounted remotely though, the smaller frame and AR size of the HC1 will spool faster and counter act the loss of exhaust velocity. So lag isn't nearly as bad as people say it is if you choose the right turbo.

WD

David Steele wrote:There is nothing recommended without a power goal every turbocharger makes a certain amount of HP efficiently or inefficiently.

Gt28RS can do 600rwhp on z32 300zx.

Its going to be a drift car but I would still like to get about 600-700whp?!

hannibal wrote:I havent even looked at single turbos for the VH, so I'm just guessing here. But I'm surprised that T04Z keeps up so well.

What keeps up so well? That 700whp turbocharger he's using at 370whp lol... and no graph.

You can easily take two TD05 14bs or 16g's and generate more low mid range hp and create the same peak HP he's currently at.

David, Ive looked for some kits for the Ford 4.6L motor. All I find are kits with "67mm" or "70mm" turbos with no mention of what frame size. Any idea what turbos they're using on this motor?

Well its actually a kit from Garrett themselves makes plenty low-mid power and can max out at 600whp.


Twin turbo is no easier to choose from then single only thing that maybe of ease is the plumbing one may do.