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-   -   Holset... anybodu tried 'em? (https://www.rx7club.com/single-turbo-rx-7s-23/holset-anybodu-tried-em-71171/)

peejay 04-15-02 11:49 AM

Holset... anybody tried 'em?
 
Just curious as to if anybody's tried using a Holset turbo on a rotary. They don't really have compressor maps available.

peejay 04-15-02 05:27 PM

I found this on the junkyard turbo site:


Go with the HX30 on the 2.3. Worked with both a 30 and a 35 on a 2.6L
Conquest. With the 30, it made boost from about 1800rpm and up, 16psi
(wastegate setting) was in by 3K. The 35 made 8 psi at about 3000, and made
16 at 4500. Overall, the HX30 was the better street turbo, and only gave up
a little on the strip to the 35. Now, if the boost were cranked up, then
the HX35 would have been the way to fly.

The car ran low 12s with the HX30, and high 11s with the HX35.

The HX30 will handle the 375hp, no problem.

The HX35 is a little big. An alternative might be the HY35, available for a
year or two on the dodge trucks. You can identify these by the non
clockalbe WG. They have a 35 compressor, but with a smaller exhaust housing
than the HX35. Kind of an HX32.

HX35W sounds about right then for a 12A. If it's a little too big for a 2.3 then it's just right for a 12A, right? ;)

spyfish007 04-16-02 01:39 AM

HX35 will be a nice turbo. My friend thinks it is a better turbo than the equilavent Garrett. However finding room and a manifold will be interesting. The Holset turbos have taller housings than Garretts so it will have to go higher up aka Apex or Greddy kits.

peejay 04-16-02 11:56 AM

This is for a 12A, going in an FB, so I'll be fabricating the manifold anyway.

Yes the big problem seems to be ROOM... looks like it may fit if it goes in FRONT of the engine... heck may even have room to retain the air pump! If the setup could pass the sniffer test, then it wouldn't have to have the stock engine and emissions swapped in every other year.

XSPOWER 04-17-02 12:57 AM

We tested the Holsets already. They don't have inconel exhaust wheels (necessary for any Rotary) and since the turbos are designed for low RPM diesels, they don't take RPM very well. In fact, I believe the Holsets are rated for use under 100,000rpm. Another thing to consider is that they aren't burst test beyond 100,000 rpm. You wouldn't want a turbine wheel going through your leg would you?!?!?

hondah8er 04-17-02 11:40 AM

My mechanic used a holset on his 1st gen with 13bre. It made 358rwhp@10psi.

I think Magnus used to use a holset (same as my mechanic) like there's on Jefferlitos third gen....but with a larger A/R. But Marco can confirm this better then I can.

peejay 04-17-02 12:22 PM

I found a compressor map on the Holset website for the HX35(W) turbo. (The W just means it's wastegated)

If I'm converting from kg/sec to CFM correctly, at a 2:1 pressure ratio it will flow from 173cfm to 552cfm. (.1kg/sec to .32kg/sec) Maybe a little too large for a 12A? Then again I wouldn't be running it at 2:1, more like 1.75:1, where the CFM goes lower still.

I'm assuming it's a 65% efficiency island that they've drawn out... no GOOD maps like you can get from Garrett. Anyway the map goes all the way up to 4:1 pressure ratio so overspeeding is not a problem. (I'm told that the -35 maxes out at 140k RPM, which is would be out at the high CFM side of 4:1 - overspeeding should NOT be a problem)

You have me worried about the turbine though. Why would it NOT be Inconel? They are, after all, the same turbo used on mid-1994 and up Dodge diesel pickups (which is why I want one - should be easy/cheap to find and get parts for) and have to put up to the abuse of running under constant stress.

92tsiawd 04-18-02 03:38 PM

Marco dynoed 470 with a holset turbo so I'm sure that it would work

spyfish007 04-19-02 12:42 AM

I personally know that Holset turbos hold up to 2000F EGT for peak temps and can easily handle 1500 to 1600 F EGTs. I also know the big Holsets turn almost the same rpm as the big Garretts (ie the T88, T100). I couldn't find the maps earlier for the medium Holsets to compare to the medium Garretts but I bet they can hold 100,000+ rpm. I've seen the HX35B hold 40 to 50 psi of boost by itself and I've seen staged turbo setups with Holsets run 80 to 100 psi. I wouldn't underrate these turbos ....


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