Cjmartz2k

I hear ya about them not giving out a lot of info on their turbo's. Holset is the OEM supplier for Every Dodge Cummins diesel, as well as a whole bunch of volvo semi trucks and a slew of others. These things are built to go hundreds of thousands of miles at 2 bar or higher. Seeing as how they supply so many Original Equipment Manufactures, they have little interest in a relativly small number of people wanting to use them for a purpose they were not intened for. BTW, they are manufactured in Hudersfield England, so maybe they aren't as hard to get as you thought The Borg-Warner's are another diesel OEM, but they offer more information and support than holset, and there is a considerable aftermarket following for them. MANY people in the states are removing GT series garretts and putting BW's on. They are real performers, especially the ones with "extended tip technology". In general, they usually outflow the similar sized holsets by a couple of lb/min and spool just a touch quicker. They do cost similar prices for the new "ETT" ones as a GT series garrett though. I'll give up a couple hundred RPM of spool time and 20hp for a turbo that costs $200USD, not $1700USD for my purposes.

300rwkw = 400rwhp'ish, right? HX35 would be the way to go. That thing would probably get you 1 bar by less than 3.5krpm--maybe considerably less. Fandango--I'm not very familiar with the turbo's smaller than the HX35. The HY35 is a single scroll version of the HX35 with a smaller ex wheel and small ex housing a/r. It supossed to be the version they put on automatic diesel pick ups to help with spool, so it should come on sooner. They do make HX25's also, but I know nothing about them. I wouldn't think that kind of power would be much more than what you could do with the stock turbo though. Is it worth it to spend a lot of money putting on a turbo kit for only 30-40hp? What kind of spool times are you wanting and what will you do with the car? You might want something like a HKS?2535 for that kind of power and it bolts right on.

Just some more info for fodder. I went out tonight on the way home from work and got some spool times. 3rd gear - .5 bar by 3.5k rpm - 1.0 bar by 4.2k rpm 4th gear - .5 bar by 3.2k rpm - 1.0 bar by 3.9 rpm

PaulR33--I just read your reply after I started my reply. I completly understand what you said and couldn't agree more. I am coming from a DIY mentality, as are most people here on Okinawa. I guess just get frustrated when people attempt to learn/discuss/try new things who would like to dable in the DIY area and others who do not want to try such things try and force there ideals on others, often with no experience. Thanks for reminding me not everybody likes new things--that should help me keep more on topic and not arguing so much with some people

You can check out the thread I started about holset turbos not more than a couple of days ago to see my specific experience with them (HX35/40 hybrid and straight HX40). I have also had a TO4e on my car (RB25 R32), and drove a RB20 R32 with a 2535 on it for a good while. A lot of my friends have holsets such as an HX52, H1E, and HX40 on RB25's and the last on a RB26. Other turbo's my buddies run on there cars are things like a 60-1 (13b), T88 (RB26), GT35r (4G63--the small one), T3/TO4e (SR, RB25, and RB20), Borg-Warner 258 (4G63), or N1's (RB26) off the top of my head. These are guys I hang out with and drive with a couple times a week. I also run against some of the local Okinawans with stuff like RB26 T88 S13's, twin TD05's on a 2J supra, and bigger stuff like that. I recently ran door to door with an older 4 door Aristo with a 2J and a T51 SPL with my current setup. I also hung on the back bumper of my buddies "togue" GTR with a 2.8L stroker, N1, cage, etc with my "laggy diesel turbo" last night up and down one of our favorite twistie roads. BTW, I'm not trying to come off rude or arguementative either. It just riles me up when people attempt to espouse the "name brand" cause with no experience other than reading something on the internet. There are some really experienced guys on here that really love garrett and I can understand that. They reccomend them because they know they work well, and I have no quarrell with them. People attacking something they have no clue about, however, I don't like. A place to come and glean knowledge from other peoples experience, as well as discuss new ideas and thoughts is what these forums are all about, aren't they?

Well, I guess having a turbo that outspools, outflows, and has terrific quality must not be a "good" turbo. Please inform me what does make a turbo "good" Not even going to attempt to back that up with any information, first hand or otherwise, are we? What kind of MP turbo were they running? Was it a big honkin' 600rwhp turbo? I wouldn't expect great spool from one either if it was, but please, more specifics to help answer this guys question. You seem to have some actual first hand knowledge on these. Completly agree, although when considering the bearing alone, BB is better. Many people think BB is the most important or even the only factor in spool time. Yes, don't stray to far from the flock. We wouldn't want anybody trying anything new/better/cheaper/different. So what's your setup jay? Have you ever run or seen anything run with an other than garret turbo? Do you have a GT series garrett on your car so you can at least indeed confirm first hand how good they are? As I have said before, I'm not trying to say my personal choice of turbo is the best out there. It has it's pluses and minuses. I am however saying people shouldn't blindly repeat what they have heard over and over again with no actual knowledge. Garrett is not the end all be all of turbos.

Man, I love how a lot of people (not all) here regurgitate info that they have read with no actual experience, or even regurgitate other peoples opinions which are not based on any experience. My second hand Holset HX40 "diesel turbo" outspools and out flows a GT35r. What's your experience with diesel turbos? Oh, and masterpower is a well repsected name brand in the states.

Here's a couple of vid of my old HX35/40 hybrid if anybody cares to see. http://videos.streetfire.net/video/R32-Sky...-car_143698.htm http://videos.streetfire.net/video/Spoolin...id-a_147457.htm http://videos.streetfire.net/video/Skyline...-ish_164772.htm

As for the "how much hp" or "which turbo for X hp", it's tough because holsets have such a wide range of compressors for each turbo, but in general at "sane" boost levels less than 2 bar; HY35- more than 450hp at the motor, but not many people have messed with them. They have a smaller exhuast wheel than the HX35 with the same compressor, and a smaller a/r SINGLE scroll ex housing. The few people I have heard running them say the have REALLY fast spool--like over 1 bar by less than 3k rpm on a 2.0L 4 banger. HX35- 450hp to 550hp at the motor depending on the compressor blade count. Spool on a RB25 would be less than 3.5k rpm. The DSM guys say it'll make a lot more than that, but I just have a tough time believing it. They are ripping off 132mph trap speeds with them though, so I guess it's possible. They do crazy stuff though like running 2.1 bar on C16 or water/methenal injection. HX35/40 hybrid- This was my first venture with holsets. I was making 1 bar by 3.5 and 1.5 bar by around 3.9k rpm in 3 IIRC. Keep in mind though, that's with cams, RB26 intake and ITB's (short runners), and no VCT. I've got a vid I'll link up later. Stock everything would spool up a bit quicker I think. I had the smaller 8 blade HX 40 compressor mated to a HX35 ex wheel/housing. I would spike it to 1.6, but it would fall off on the top end to around 1.4 bar. I was making mid 500's at the motor with it. This is the one I pegged out a Z32 MAF with. HX40- Capable of around 500-600rwhp depending on the compressor. The smaller 8 blade is what I had making mid 500's at the motor. The 6 or 7 blade compressor is the bigger one and it's a 69lb/min compressor and it's what I have now. With a 19cm housing, I make 1 bar by 4.1k rpm in third gear and 1.5 by less than 4.5k rpm. HX52- This thing is huge. Like 104mm exducer and 72mm inducer IIRC. My buddy has one on his RB25 and makes 1 bar by under 5k rpm with big cams and a custom intake and a 16cm ex housing. He stopped turning up the boost around 1.4 bar because he was over 95% on 740cc injectors at a/f's in the high 11's. Make of that what you will, but that thing scares the CRAP out of me. It's in a S14 sylvia BTW. He will pull hard on stripped out, T88, RB26 S13's at our local drag spot. He's currently looking for a tripple plate and 1000cc injectors. Discopotato-- Thanks for the input and I want to reply in depth to some of the issues you brought up, but I want to take the time to respond to everything in detail, so it's going to have to wait until I get home. Quick summary though, these things are BEEFY and while I don't know the metal composition, I can assure you running them in a gasoline applicaiton will not be a problem (except in the case of the newer ones with variable a/r ex housing--which people have started using in gasoline engines already, but I have my doubts about thier longevity). The other big thing I wanted to bring up is it sounds like you believe these turbo's to be slow spooling due to lack of BB CHRA's. These are bush bearing, but they outspool there respective sized Garret BB counterparts. They are indeed twin scroll (split pulse) with the exception of the HY and some other strange one off applications of HX40's. The wheel design is MUCH better than Garret's design and as I'm sure you know, wheel design is much more a factor in spool time than whether or not a CHRA is BB. Now combining the two like you mentioned would indeed make an incredibly quick spooling turbo, but it would defeat what is, in my opinion, the best part about these turbo's. Low price. They are so cheap not from the factory, but surplus on ebay. They come in a miriad of Semi-trucks and busses, and make thier way to ebay all the time, never being installed. I got my HX40 used for $200, and my buddy got his HX52 new from ebay for $450 plus shipping to Okinawa. I've got many more expamples, but get on american ebay and search "holset". You'll see. The one downside you brought up I can agree with is the frame/overall size and weight of these things. They are BIG. Compare my HX40 next to a GT35r and it dwarfs the garrett. It does as I mentioned however, outspool and outflow the Garrett. OK, sorry, that wasn't so brief

At the wheels or motor hp? You could make 550hp at the motor with the 7 blade HX35 and I bet it would be at 1 bar by 3.5k rpm or less. If you want that kind of power at the wheels, you need a 6/7 blade HX40. Mine is making 1 bar by 4.2k rpm in third with a 19cm housing and I'm making that kind of power. That link has a good write up that I used as info when I was first researching these turbos. It focuses mostly on the smaller holsets, so it's especially good if you want to do togue or something like that.

**Almost forgot the whole point of these turbos. They go new shipped on american ebay for under $500

I started a thread on them, but I think a 7 blade HX35 might be close. I'm not sure what GT30's can do on the top end, but I think the HX35 might be a bit smaller than one. What are the demensions of the compressor wheel? <----please answer in the other thread. http://www.skylinesaustralia.com/forums/Ho...-s-t247809.html

I've had a lot of questions about the turbo I'm running, and I didn't want to get another thread too off topic, so I'll put some info up here. Just for reference, I have the 6 blade HX40 with a 19cm T4 holset housing. A large majority of the info I have I gleaned from the DSM forums which is the is 90's american version of the Evo. They all have 4G63's in Mitsu Ecliplses and Eagle Talons, and most of the guys on this site have AWD versions. Anyways, I'll post up some general info they have on holsets and get into more specifics later if anybody expresses interest. Also keep in mind most of this info is geared towards 4g63 applications, so they talk about BEP (Bullseye Performance) housings Again, I don't want to take credit for somebody else's work, so here is some info from THIER page. Summary provided by wiseman, Dsm-onster: HX35: The 8blade hx35 has a 56mm compressor inducer. This is found on 1995-1998 cummins manual pickups. The compressor flows 52 lb/min according to the compressor map. The bolton BEP housing (0.55 a/r) is enough to push the limit of the compressor. There's several 500whp 8blade hx35 cars out there with the bolt on housing. It reaches 20+psi by 3500rpms in 3rd with 272 cams. Smaller cams would equal a faster spool speed in most cases. The 7blade hx35 has a 56mm compressor inducer. This is found on the 1999-2002 cummins manual pickups. The compressor flows 60lb/min according to the compressor map and logged results from a member here. The bolton BEP housing with the hx35 turbine wheel do not SEAM to have enough flow to really reach the potential of 60lb/min. But many have logged over 50lb/min so far and seen 500whp. The stock hx35 12cm^2 twinscroll turbine housing is a t3 flange housing. This mated to a NON-divided runner manifold has produced a 132mph trap speed with a full weight 1g AWD. This is about 600whp. So the flow is there with the stock housing if you use a non-divided manifold. The spool speed of the 7blade hx35 is similar to the 8blade hx35 with 20+ psi by 3500rpms in the bolton housing and by 4000rpms with the stock housing with a non-divided manifold. HY35: The hy35 has a smaller turbine wheel than the hx35. And, it has a turbine housing connection that does not allow for a bolton housing to be used. It does not have a divided housing so any t3 manifold can be used effectively with this turbo. It has the same compressor as the 7blade hx35. We don't know if te hy35 turbine wheel and housing is enough to reache the 60lb/min potential of the 56mm 7blade compressor. Some one try it out already!!! It should at least be a faster spooling viable option to the full t3/t4 50-trim. H1C/WH1C: In 1994, there was the Wh1c which has pretty much the identical compressor as the hx35 but with a Vband compressor cover. The turbine wheel is the same. It will bolt into the BEP bolton hx35 turbine housing. It has 4 bolts at the housing instead of 6. So you will need to buy 2 more bolts and use 6 washers cut to make a flat side. Honestly, I just used bolts that were cut a little short and the bolt head was wide enough to pull the chra to the turbine housing. No sealing issues. Since the Wh1c is for all practical purposes an 8blade hx35 the spool and flow is the same too. I have the big h1c. It comes on the INTERCOOLED 1991-1993 cummins pickups. It has the webbing for MWE but no groove cut like the hx35/wh1c has. This turbo I term the big h1c because it has a 54mm compressor inducer and same exducer than the 8blade hx35/Wh1c. The other h1c is the small h1c found on the NON-intercooled cummins pickups. This has a 50mm inducer but only 7blades and has no webbing for MWE. Less blades helps flow, but so does a larger inducer diameter. The most whp ever recorded on a gas 4cylinder with the small h1c was done on a KA24 nissan: 411whp. Since the big h1c has a 4mm larger inducer and the same turbine wheel as the hx35, it is safe to say that it flows enough for between 411whp and 500whp. The diesel sources state that it flows SLIGHTLY less than the early hx35. So 4lb/min less than the 8blade hx35 puts the flow of the big h1c at 48-49lb/min right where a 50-trim or 20g is. The small bep housing is all that's needed to get the most from the compressor and the spool speed is 20+psi by 3500rpms. HX35-40 hybrid: Keeping the long tradition of the marriage of sportcompact and hybrid turbos, there is the hx35 turbine and the hx40 compressor. It is strongly recommended to use the large bep turbine housing or the stock hx35 turbine housing with an non-divided t3 manifold for this turbo. The small bep housing around a t31 size hx35 turbine wheel is probably not enough to merit any of the hx40 compressor wheel upgrades. 20+ psi by 4000rpms can be seen in the hx35/40 with the hx35 12cm^2 turbine housing with a non-divided t3 manifold. With the large bep housing, spool times are to be determined. But likely similar. HX40: The 8blade hx40 has a 58mm inducer and flows about the same as a 60-1 (around 60lb/min) with ALOT better high boost efficiency and spool speed. It is the most common hx40 out there. The small bep housing with the hx40 turbine wheel is plenty to reach the full potential of the 60lb/min 8blade hx40 compressor. 20+ psi by 4100rpms with 272s. The 7 and 6 blade hx40 is called the super40 and has the 60mm compressor inducer. This compressor flows around 69lb/min. You can get this wheel in billet style (think HTA). The non-billet wheel spools as fast as the 8blade hx40 in the bolton bep housing and has done 653whp at 40psi per the holset results only thread. Billet should spool even faster. The t3 .70 a/r BEP housing slows spool about 400rpms. But reports show a significant gain in flow per psi. So expect more power at lower boost with that turbine housing. H1E/WH1E: The Wh1e is like it's little brother the Wh1c. It mirrors the hx40 8blade in every way except that it has a v-band compressor cover and a 4bolt chra-turbinehousing pattern. It will consequently bolt into the hx40 bep bolton turbine housing and this is plenty of flow to max out its 60lb/min compressor. The h1e is like it's little brother the h1c. There are different size compressors. . . BUT there are also different size turbine wheels too. Check measurements before buying this turbo if you plan on running a BEP turbine housing. There are lower flowing compressors than the 58mm 8blade that are out there. So this turbo may not flow any more than an hx35 if get the wrong one. You need at least a 58mm compressor inducer for this to be a worthwhile turbo vs the proven hx35 or 8blade hx40. HX52: This is a big sucker. It is commonly found on the Volvo Semis and usually has a billet compressor wheel. It flows 88lb/min. There is no bolt on housing for it. If you want a bolton housing for this turbo, then you don't want this turbo. In fact if you want a t3 flange turbine housing for this turbo, then you don't want this turbo. You DO want this turbo if you're looking at a gt4294r or gt4202r. The turbine inlet is slightly different than a t4 bolt pattern. You can still get the t4 manifold to work just fine by enlarging the bolt holes. Misc.: Holset's don't spool slow. They spool faster than their garrett or mitsubishi counterparts. Diesel exhaust is cold and slow moving. The holset turbine wheel is a work of art. It has been shown to flow very well in a very small turbine housing. For example the hx40 turbine wheel in the small .55 ar bep bolton housing flows as much as a garrett gt35r turbine wheel in a larger .63 ar garrett t3 turbine housing. The hx40 with this configuration spools about 500rpms faster! You can upgrade to the .70 a/r BEP t3 turbine housing and have the same or slightly faster spool speed as the above gt35r with ALOT more flow per psi and consequently more horsepower per psi. This makes for VERY good pumpgas numbers. Holset patented map width enhancement. They do not have extended tip technology, but there compressors show more efficiency than their garrett or mitsubishi counterpart. They have superback technology witch leads to VERY, VERY durable compressors. The are designed to be overworked and underpaid. There are discrepancies all over the web concerning the compressor maps. Take what you hear/read with a grain of salt and a shot of tequila, and the worm. The holset is fine with stock 4g63 oil pressure from the oil filter housing. If you have no b shafts, you'll need a restrictor. The drain line is a garret bolt pattern. The feed line is different for different turbos.l

Short sidetrack then. The HX40 I'm running has a 60mm inducer, 85mm exducer on the compressor side, and 19cm (ballpark .84 a/r) twin scroll T4 ex side. I'm at 1 bar of boost in 3rd by 4k-4.2k rpm on an RB25 with 264 HKS cams, no VCT, and a 1.2mm Tomei HG which probably bumps the compression down a little. O yeah, and like I mentioned before, stock RB26 intake with ITB's. I do think aussie hp numbers tend to be a bit more conservative than numbers over here (which I like), but if I had to guess, I'd say I'm mid to high 500's at the wheels. Tick that down a few percent to equate with your guys numbers like I said. I pegged out of z32 MAF at 5.15v a long time ago with the old turbo (Holset HX35/40 hybrid) and this one pulls more than a fair bit harder. I know this will rile a lot of guys on here up, but these things out spool and out flow GT35r's all day long. O yeah, and did I mention I got the turbo new for $450USD shipped from ebay? It came on volvo busses If you guys want any more elaboration than that, I'll start a new thread.

Those displacement and hp figures are on diesel engines spinning to 3k rpm max. A good ballpark firgure for diesel turbo to gasoline application is mulitply by 2 If you have any doubts about holset turbo's on gasoline engines, google "holset DSM" for a wealth of info specifically on guys running them on 4G63's (Evo motors). This thread is about what RB25's will do though, and not holset turbos, so I don't want to sidetrack the thread to much going on about them. PM me or start a new thread if you want to go into them further.

Mine's still kicking. I'm full HX40 (19cm ex housing) which is a 69lb/min compressor at 1.7 bar, now with 264 cams, 1.2mm HG, RB26 ITB's, and still the same stock bottom end. We still don't have a dyno anymore on island (well, it's still there, but they won't run it--it's a dynojet anyways). I ran out of Z32 MAF a LONG time ago, so we moved it to 100mm piping. I've got 860cc no name injectors that are sitting just over 70% duty cycle with a/f's right around 12:1. You can do the math on that. I run with some of the faster 2wd guys here on the island with built RB26's and smaller T88's (in S13's), but I think they have a pretty rich/retarded tunes judging by the fireballs they shoot and the fact I'm hanging with them. The guy that owns the shop I hang out at put a Holset HX52 (90lb/min) on his stock bottom end RB25 with a completly built head (solid lifter, tomie everything biggest cams they make for the 25, yada yada) and he stopped turning up the boost at 1.5 bar because he was tickling 95% injector duty cycle on 740's. He also just had his twin plate start slipping on him, so we haven't had a lot of time to play with it yet. I can't remember if it was this thread or the other where somebody was questioning the hp guesses I was making with my old set up due to my 122mph trap speeds (with full weight--subs, full interior, random crap in the trunk, etc.), so I won't make any here. I'll see if I can get the Gtec from my buddy again and get some new trap speeds, but I spin even in 3rd on 275 nittos, so I think that's skewing my speeds a good bit. *edit--I do is 4-5 quarter mile'ish runs a week on average with the occasional playing around in the twisties, so I'm not road course racing it all the time like a lot of you guys. That might help longevety.

I know somebody that just got a dataloggit last week and had this same problem. He had to break the little plastic piece in the off to make it fit.

Pistons would be what I would replace first. 2rismo--what are you talking about? Low 120's is just fine for 500rwhp. I will say the mph is on a gtech, so it might not be all that acurate, but still, 120's is 500rwhp territory. I might be HIGH 400's at the wheels, but that's not enough of a difference to try and say somebody is full of it over. Keep in mind, I'm spinning WAY past the 60' with 275 nitto's on these crappy Okinawa roads, and I'm not as light as you think with subs, full interior, my fat but, tools, etc. Traction can actually effect mph when you are spinning as much as me. Also, there is such a wide varience of mph to hp for turbo cars, it's tough to say what's what. Look on dragtimes.com. There is a timeslip which I'm guessing is you that matches your times and car, and then there is another R33 making 603rwhp ripping off a 10.6@128mph (with a 1.5 60' mind you--I tick off 2.1's on nitto's here because of the roads and not track). There is also a GTR with a TO4R @ 22psi that doesn't have a dyno, but that's easy 600rwhp and he's doing 10.7@130mph. So in summary, I'm at least high 400's rwhp, and as it pertains to this thread, RB25's can handle a lot more than a lot of people around here give them credit for.

I have a greddy type R and it's the only one I would reccomend (other than stock GTR's). Mine is also tightened down to the point where it only really blows off when I get up above 1.3-1.5 bar'ish. I like the flutter noise. I reminds me that I don't have a gay HKS SSQV limiting me to 1 bar of boost. I always get a kick out of some goober with a stock turbined R33 telling me I should get a BOV, and than opening the hood for them

exactly the way I use mine

It should have more lag now. I've had first hand experience with this. It's likely you feeling the difference because you want too feel it.

I've been running one for a few years. What do you mean by abuse? Mine has been heat wrapped most of the time, and I've been making over 400rwhp for like 2 years. 500rwhp for about a year. The are beefy as anything out there and I couldn't see how it would be possible to crack one. The only advantage I can think of for the bottom mount is that it's a straighter shot for the exhuast. It doesn't have to make those 2 near 90 degree bends. I don't think it's much of a benefit though.

That doesn't sound like a to much hp problem to me. Especially it being forged parts.

http://www.skylinesaustralia.com/forums/search.html

Well put about the track vs. street car, and it's something to consider. I daily drive the car, and it only sees 4th gear pulls or better 1 or 2 nights a week drag racing, and than only 7-8 runs a night. No extended autocrossing or drifting. Also, like I said, I'm more willing to push my motor because I have access to $300 replacements. If it lasts 2 years, I'm happy. The 400rwhp was on a dyno. Now, it was a dynojet style dyno, so I'll give you the fact maybe it will read higher than some. I am at sea level (literaly), so that helps. Also, the tune had pretty agressive timing maps on a stock 9:1 compression with 12.1 a/f ratios. It was set to 1.2-1.3 bar, and falling down to .9-1.0 bar around 7.5k-8k rpm. It was the big T04e with a .82 a/r ex housing also BTW. Whether or not I was making 400rwhp or not on the T04e or not (if not, it was damn close), I certainly am making a lot more than that now. The DSM (Diamond Star Motors--a mistubishi/chrysler colaboration) guys are making 600awhp on my current turbo. I've been on that one for over 1 year making a best guess of right at 500rwhp (120+mph trap speeds, and maxing out a z32 MAF). That previous dyno doesn't have anybody to run it anymore, so I can't get on there.