I'm a boost addict brosef. The only reason I have a KA in my 240 is because I lacked the funds and time to do a V8 swap. This thread popped up on the active topics list and the title got my attention right away. I love discussing turbo's and projects man. Especially boosted V8's. The motors can change but the theory behind adding a turbo remains the same.LEMHEAD16 wrote:WD what are you doing in the VH forum? I thought you were banished to KA-T long ago?
The T2 flange turbo is a restriction on the KA24DE at anything more then 8 psi. They are better matched to the SR20 or smaller motors. People use them on the KA, but only because of how cheap the manifolds and supporting stuff from China is.karay240 wrote:So let me get this straight. A T28 (or whatever's eqivalent) is OK ONLY for a 2~2.4 liter 4 cylinder to make up to (or around) 400HPish, but NOT ok for a 2.25 liter 4 cylinder trying to make 200HPish. It's not enough turbo??? Come on.
LEMHEAD16s' goal is 375-425HP. Most of these suggestions I'm seeing here are for double the power goals. Just think 2.25L 4 cylinder, and it's a pretty anemic little thing barely making 140HP. Just put 2 T25 or T28. Stock S13 turbos will be the cheapest and will EASILY get you 400HP. I would suggest going T28 (used S14 or 15) which is more than enough turbo for your goals, and when you get used to (or outgrow) the power, you can install GT2871s w/o any modification.
The only thing w/ the t25/28 is that at higher rpm, the internal wastegate can't handle the pressure and boost tapers. That's a problem with a little motor like the SR that NEEDS to rev to make power, but think double w/ the VH
Fair coment! I was a little hyped after reading several posts that just told everyone how great he is and basically no one else knows anything. So yeah I should have stopped and taken a breath before postingWDRacing wrote: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.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.
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
That is probably the most accurate way to describe the perfect trim turbo. What unit(s) will provide the best power curve the most efficiently. For me a slight bit of lag can easily be sacrificed for a more efficient turbo when dealing with a V8 application. The immediate "out of the hole" torque is already present.darinz wrote: So yes power goal is very important for specing the turbo (of course) but how the power is delivered ultimately is the important thing.
You just hit peak power much sooner t28's they can do 270 whp and peak out at what 16 psi....that's stupid driveable.WDRacing wrote: The T2 flange turbo is a restriction on the KA24DE at anything more then 8 psi. They are better matched to the SR20 or smaller motors. People use them on the KA, but only because of how cheap the manifolds and supporting stuff from China is.
Also, the waste gate isn't what causes the boost to taper off at higher rpm with a T25. It's the tiny compressor not being able to support the volume of air. Which makes me ask, why go to the trouble of setting up a twin turbo intercooled system when you go in knowing that they are to small? I'm not a big fan of fabricating and investing in something that is 100% maxed out upon install. That's never a good plan IMO and running twins complicates the plumbing far more then necessary.
For the record, the T28's that make 400 whp on any motor in singular form cost about $1300 and have a T4 compressor. There are 100's of trims available for almost any combination but we're talking about what works well vs what can be thrown together. Especially if you're ok with buying a used turbo, the options are limitless for very good prices. Hell 2 RB25 T3 turbo's would be WAY better then SR T25's if you're stuck on twins.
Point being, there are so many great turbo's available right now, used, why not choose the best one (or 2) for the job?
WD
Unless you've done this conversion you'll find out that there is space there isn't anything to harm. Jeff Taylor used/uses a single turbo setup.karay240 wrote: BTW, I don't really get how ppl argue that the single turbo set-up is less complex. I'd rather rout charge piping around the engine bay than exhaust piping around the engine and other vital components worrying whether or not it'll get too hot.
You are going against your earlier post.WDRacing wrote:You might hit boost earlier with a turbo that is to small, but a properly sized turbo will make gobs more power with less boost.
Let's stop using sayings here that can get out of hand. Simply, if you want an X amount of HP you use ''this'' turbo.Also...you don't use turbo's that have no top end on ANY racetrack.
No, you're just not comprehending my point.David Steele wrote:You are going against your earlier post.WDRacing wrote:You might hit boost earlier with a turbo that is to small, but a properly sized turbo will make gobs more power with less boost.
Let's stop using sayings here that can get out of hand. Simply, if you want an X amount of HP you use ''this'' turbo.Also...you don't use turbo's that have no top end on ANY racetrack.
The compressor is probably perfect, what exhaust housing size were you looking at?Carl H wrote:strap on the 'small' gt42...equivalent to the hks t51r kai.
did the math and its BEAUTIFUL on the VH.
LEMHEAD16 wrote:t3/t4 50 trim x2 =fun
Carl H wrote:strap on the 'small' gt42...equivalent to the hks t51r kai.
did the math and its BEAUTIFUL on the VH.