MooreBoost

+1 i noticed that about rob too. pretty soon he will say to just install a ls1 and be done with it..

dnovak

Disadvantage on the Holset is the need for a oil restrictor because there is only one oil ring. I have had a second one machined into the shaft and it seamed to eliminate the need for the oil restrictor. The up pipe does need to be changed but it is well worth it. Holset wheels are a great option for these cars and you should not be afraid to use them. I am not so worried about the heat on the turbine because they,Garrett Holset etc all use a grade of stainless close to inconel. even if the shaft and turbine was made from 304 it would be safe at a 1650 for extended periods. The things I always worry about are compressor wheels over spinning but this is not a problem in our rides. I have had a holset come apart at 45psi on a old 24V cummins but that was not a billet wheel. On my current cummins I force 20PSI of hot air into my high pressure turbo taking it to 50 PSI and very hot before it hits the cooler and anyone who knows me knows I drive hard and abuse my cars/truck... AS for holsets spinning up nice we ran a HY35 compressor in an H1c Housing with a Garrett .63 turbine housing with a HX35 Turbine and it started to spin before 3k and never gasped for air. there is a turbo in my shop right now that belongs to a fellow lister and it is HY35 in a #8 housing,.,, I just need to get off my but and make the pipes and send it out for testing. anyway I am pro any turbo that makes the cars faster

dnovak

So, hx40s will fit under with minor grinding to the intake and pedestal but my highest concern is what you spoke of and that its heat soak. The factory turbo has a water cooled center as we all know but as far as I know there are no holset turbos that have this option. I might be wrong so don't hold me accountable if you find one. So the holsets not being water cooled, bigger and under the intake would of course cause more of a heat soak problem, this is obvious, but with the correct insulation and heat Shields this can be corrected. The bearings, shaft size and general size of these turbos plus the simplicity of rebuilding makes them a great option. The Garrett VNT that I am working with now that will be going on a newly designed motor here in a few months has a T4 inlet flanged outlet, water cooled center and even fits on the pedestal. This its the turbo that I spent a pretty penny on ceramic coating internals and veins for longevity. If you get a change and really want to see the hx series stuff go find your local diesel shop and ask then if they have a core to look at. Btw you can see the vnt turbo in the vnt thread

dnovak

I think you can loose up to 200def between the exhaust port and the turbo so that helps out the argument supporting the holset.

Dougs951S

Rob, if you look back a page, I DID provide rebuttal and sources to the contrary. I think its important that we as a community combine our knowledge and ideas to the best of our collective ability and stop being afraid to push the envelope. Just because a part wasn't specifically made for a porsche by some boutique supplier and doesn't cost 2000 dollars doesn't mean it cant work for our cars or that it isnt possibly even better than what of the other guys are running. Look, this is a 25 year old platform we are working with. If we think ourselves into a box, forward development for this platform will die. Lets all strive to prevent that.

Dave, you mentioned you had in your shop a turbo belonging to a fellow lister that used a number 8 hotside and stock up/down pipe. Was that a genuine, or a replica #8? I am also interested in how you used the HY compressor in your turbo, as it was my understanding that that compressor section was not suitable for use with our cars do to the way it connected to the center section, or something like that. Is that why you used the H1C coldside? Could you put the HY35 compressor inside an HX35 coldside and use that? Love all the great knowledge on this board.

blown 944

I'll answer. Actually I did earlier .

yes you can use an HY compressor wheel in an H1C. We used just the center section and compressor housing for a donor. The hot ticket is to get the 7 blade billet wheel

You cannot use the hy wheel in the hx housing. The wheel is smaller.

Again though IDK about the hotside

blown 944

Ok, yes there are very few running them.

Take a closer look at the mph... The hx 40 (probably not even a super 40) is 118 in the 1/8th and 150 in the quarter. Now analyze the rest above it for mph and what turbo the have. Now, Also consider that as you go up the cars are most likely lighter.

IMO when you compare the mph, and compare what other turbos they are up against, IMO it makes it even more impressive.


I'm sure you don't see it that way, but I personally think its very impressive.
Thanks for the link.

Remember the hx 40 is a 60mm inducer...fighting well above its weight against gt37, gt42, 70mm turbos.

Again though, I'm not sure where your fight is in this?

333pg333

Sid, for a circuit car vs a drag car, would you still suggest a like for like Holset? Like for like being engine size, breathing etc...

blown 944

Pat, I like the Holset design. If you choose the correct turbine housing, along with either the 35 or 40 compressor (depends on hp goal) you have a tough turbo from 300 hp to 600 hp.

The bearing design is much stronger and therefore the durability is in its favor.

There are many ways to get the job done. IMO "getting the job done" repeatedly counts for something.

My .02

Dougs951S

Realize also that many of those cars at the top of the list are running nitrous, something our community tends to shy away from. "you cant run NAWS on a porsche man, you'll blow it up!"

Rob, the point I was trying to make with those two links was their durability. Both threads stated the turbos made great power and were durable at over 30 psi. That evo went 139 with it, and that dsm made some killer power. The holsets have also been proven to NOT be laggy so I dont know where you are getting that information. You can't compare the dyno graphs when we are working with at a minimum, 25% more displacement than the dsm guys.

333pg333

Hell yes Sid, that is a big plus in my book too. I’ll have far more immediate issues than just where my turbo is spooling but it’s always good to see that you’ve had great results with these having beaten on them. By the sounds of it you’re getting good spool and a very decent curve. I’m going to try this BW 362 turbo for now and hopefully it will be fairly decent. However with all the extra room under my hood it’s nice to know that there are some viable alternatives on the horizon.

67King

You need to call Charlie at Evergreen. He builds pretty much exactly what you are looking for - a Holset cold side on a -8 KKK hot side plus cnter housing. if you've got donor K27/8, it probably will be pretty inexpensive. I actually have one, brand new, never istalled. I may not use it, not sure as my 2.5L 8V project is now a 3.0L 16V.

As for the little pissing match going on here, I'm not going to get into any kind of argument, as I know I'm a pretty argmentative SOB. But I've dealt with this crap directly on my own cars, and also when I was at Ford at the OEM level.

The metallurgy is very important. I has to be designed to handle the heat that will be thrown at it. Heat is more than just EGT's, but that is one factor. OEM example - the V10 3V Modular Ford makes uses cast stainless manifolds. Not a turbo appliction even. The V8's don't, but they aren't rated to tow what he V10 is.

Also, FWIW, the source linked early on I think said diesel EGT's were 500-800F? That's way low They aren't 1800F like gasoine, but a whole lot higher than 500-800. 1200-ish, I think is the high end?

Most OEM's run tubos very rich, to lower EGT's. I cooked a Garrett T3 housing by leaning it out to 12.0:1. I was making stupid good power from that litte turbo, but I killed it. Gasoline turbo, gasoline engine, and I still killed it. Note that this was in a 2.3 Turbo Ford - the turbo was mounted directly on the log manifold.

When I was into the turbo Ford scene, lots of those guys were running the Holsets on their drag cars. They made good power for not a lot of money, were very happy with the spool characteristics, and didn't have durability issues.

I've had a few custom turbos made by two different turbo builders. Evergreen being one, and the other guy was Turbo Concepts in Brighton, MI. Neither of those guys would build a Holset based turbo for me. The diesel turbos wren't designed to handle the heat that gaoline turbos were made to handle.

Now to get back to the whole heat versus EGT thing. Both Nick and Charlie knew that I'd be on race track. So it isn't just EGT's, but duration. That has a much more strenuous environment than drag racing. The housing probably won't come close to a solid equilirium tempterature in a drag race, but over 30+ minutes at, oh I don't now, 60+% of the time at WOT, that turbo is going to be much more heat soaked than 10-14 seconds.

Another factor is how much heat is lost or retained through the manifold. The 951's layout doesnt exactly lend itself to retaining heat to the turbo. So unlike my old 2.3 Turbo, the 951's turbo probably won't be sinking a whole bunch of heat, it'll be lost though the manifold.

In other words, a 951 that gets drag raced is probably not going to be very constrained to more expensive metallurgy. If you've got a more closely coupled turbo, and you are on the road course, you are going to be much more likely to run into problems.

Another factor that may or may not have been mentioned (I skipped the last half of the thread) is the oil supply. To my knowledge, most turbos have their oil supply coming from the cylinder head, which is to say after an oil restrictor. On ours, it is fed from the bottom end, so it will be seeing higher pressure. I've read on here a few guys with Garett based systems having issues from oil pressure. I haven't played with any of that, but deferring to what Charlie (Evergeen) has seen, which is a whole bunch of 951 turbos, he sticks with the KKK center sections, which are designed for the higher pressure without needing an oil restrictor.

blown 944

While I'm not exactly sure why they would refrain from using the majority of a Holset I would venture to guess that it has to do with the ability to just use the Holset compressor wheel in a kkk turbo. That is a popular mod.

He may like using the KKK turbine wheel as it has two sealing rings. Personally I use a small restrictor (.080).

I will do done research on the hx 40 turbine wheel material. Iirc it is inconel. We use garret hot sides, so the turbine housing material is irrelevant.

I'll say this, to make any "real" power, there is no way I'd be using a Kkk turbine wheel. It's a crappy design and not very large.

Obviously, not many people use them, but I bet I can find where they've been used in other motorsports besides drag racing. I do know they have been used in the standing mile. I also recall that one was used on a track car in new Zealand. Iirc it was the whole turbo, hot side included.

Either way, I won't be changing anytime soon

V2Rocket

Would e85 allow for longer turbine life since its said to burn cooler (if tuned properly)

blown 944

Well whenever you're ready to find out how much of a POS my Holset is I'll be glad to show you.

Not only can you have your V8, I'll even let you bottle it.

..... Let me know....

You throw down some money down on it... I'll drive down there and take it.


It should be a suckers bet for you.

1) you don't think my car will run for **** at low elevation.
2) I'm running a POS Holset
3) you have the almighty LS conversion
4) you know it all


Put up or shut up. Whatever race you want, road, drag, roll on... Name it.

I'm sick of reading your smack talk about the inferiorities of my setup.


Bring it!!!!!