Holset H1C Information

[Dieselboy]

I snagged a good deal on another turbo; this time its of the Cummins variety.

I've found a Holset H1C, and from what I've found so far it seems to have an 18 cm impeller housing. That's way too big. I was thinking that a 9 cm wastegated housing would work well with a 6.2/6.5 flowing 80+ cu mm of fuel and shooting for 20 psi max boost.

It looks like it has a standard T3 flange, a 2" compressor outlet, and 2.5" exhaust outlet. It seems a bit small.

I can't find a compressor map on the Holset website, and I don't know what pressure ratio these turbos prefer.

Does anybody know anything about these turbos? Brittanic, Grape?

[grape]

those things really aren't efficient at moving any air untill you get the pressure ratio way up over 2-1. I think arveetek is having the same problem, it sounds like his turbo is a v trim t04 b impeller wheel, which likes to have the crap spun out of it to move any air. If He'll take the inlet housing off and measure the inducer and exducer i can tell you what it is, but i think i know. If I were you I'd buy one of those Master Power brand 60-1's with a .68 euro style exhaust housing with v band already on the turbo. What those have is the big P-trim exhaust wheel(industry standard for performance stuff) and the euro housing uses that big wheel but with a T3 mounting flange, just like the banks and the gm stuff. There is a group buy on those turbos on www.turbomustangs.com (http://www.turbomustangs.com) and I think you can buy a complete unit for less than $500 brand new. I'll say it again, we shouldn't need 20 pounds of boost to make 250 hp, that's just retarted. I'm going to email you some pictures of what mine looks like, 4" inlet and 2.5" outlet with a 3" exhaust outlet.

[Dieselboy]

Originally posted by grape:
[QB...I'd buy one of those Master Power brand 60-1's with a .68 euro style exhaust housing with v band already on the turbo. What those have is the big P-trim exhaust wheel(industry standard for performance stuff) and the euro housing uses that big wheel but with a T3 mounting flange, just like the banks and the gm stuff.[/QB]Wouldn't the .68 or .70 ratio be a bottleneck on the exhaust and result in high EGTs? I remember .81 or .84 being the normal a/r ratio for the GM turbos, and they're considered restrictive at a point.

Is a regular internal style wastegate housing available on this series turbo?

[grape]

that's the whole point of the p trim wheel, the gm series turbos use a true t3 exhaust wheel which is dinky. A euro housing lets you use the T04b based p trim exhaust wheel with a T3 mounting flange. The exhaust outlet is a full 1/4" bigger in diameter than the gm turbo's. You can't compare a/r numbers if the wheels used are different, it's like apples and oranges. And no, those turbos require an external wastegate......like my 42mm Racegate. You can use the small a/r housings to get boost up quick as long as you have enough volume of flow through the wastegate to not choke the engine. I think the gm wastegate is slightly under 1.25", my racegate is 1.625". should be plenty, I want boost up to about 6 pounds by 1500 rpm, and then it can slowly creep up to around 12 pounds and just stay there.........that's plenty of air for what I'm doing. I think at 12 pounds the inlet wheel I'm using moves 40 lbs. of air per minute, which on a diesel is enough for a little over 300hp.

[dieseldummy]

I have a friend that is trying a HY35 Holset of a late model Cummins. It will easily make 12lbs of boost by 1500 RPM and make an unreal amount of boost in the top end. I'm not sure how it would compare to the H1C, but I thought it might be relavent. If you are looking for lots of boost, then a Holset is the way to go. The more boost these engines get the cooler they run, at least intercooled. Good luck.
Justin

[Ratau]

Grape, David

I gathered lot off info what to use, it seem that most off the manufacturers use their own specifications if one talk about wheel size. Will you please commend on this combination using Garrett components:
Turbine housing A/R .84 (what wheel?)
Compressor housing A/R .60 with a 60-1 wheel
External waste gate 38-40mm (is this

[grape]

the only way you can get the 60-1 inlet with the .6 a/r is to get the 60-1 hifi, which is basically the housing of a T04 b, machined to fit the larger wheel. The b indicates housing family size. The b is the same as the banks, and very close to the gm turbos, that is 3" inlet 2" outlet. However i think the gm's are 2.5" outlet. My 60-1 wheel is in the T04 S housing which is the next step up and identify-able by the 4" inlet and 2.5" outlet. Supposedly there is only about 10% diff in flow between the two setups, but as long as I was building something, I'd go for the shock and cool factor with the huge inlet housing. If you look on turbonetics.com you can see all the deminsions of the various exhaust and intake wheels, sort of interesting. You can see how dinky the t3 exhaust stuff really is.

[Dieselboy]

Yeah, after sending an email to a few of my Cummins friends, I'll be selling this Holset. Like grape said, the 5.9L spins these things pretty fast. It's much faster than our exhaust gas will want to turn the turbo, so surging would be a big issue.

I've been looking closely at the Master Power series, and I do like the 4" inlet and 2.25 or 2.5" outlet. The impeller housings have a good sized exhaust exit, so there wouldn't be a huge bottleneck on the exhaust. I also like their competitive pricing. The only drawback is the cost of an external wastegate.

[grape]

i found my Racegate on ebay and bought it for $200. New they are about $420, best part about it, was he got my check and I actually got the racegate. I also considered using two deltagates, which are 35mm and can be bought for about $100 each. So either way, the $200 I spent was all i budgeted for wastegates, that either being 1 big one or two little ones.

[arveetek]

Originally posted by grape:
those things really aren't efficient at moving any air untill you get the pressure ratio way up over 2-1. I think arveetek is having the same problem, it sounds like his turbo is a v trim t04 b impeller wheel, which likes to have the crap spun out of it to move any air. If He'll take the inlet housing off and measure the inducer and exducer i can tell you what it is, but i think i know. Could you care to explain to this newbie to turbos what you just said? tongue.gif Can you comment some more on my turbo and results?

Casey

[Dieselboy]

Just in case anybody was interested, the turbo has found its way onto ebay:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7910920660&ssPageName=STRK:MESE:IT

[Dieselboy]

Originally posted by grape:
the only way you can get the 60-1 inlet with the .6 a/r is to get the 60-1 hifi, which is basically the housing of a T04 b, machined to fit the larger wheel. The b indicates housing family size. The b is the same as the banks, and very close to the gm turbos, that is 3" inlet 2" outlet. However i think the gm's are 2.5" outlet. My 60-1 wheel is in the T04 S housing which is the next step up and identify-able by the 4" inlet and 2.5" outlet. Supposedly there is only about 10% diff in flow between the two setups, but as long as I was building something, I'd go for the shock and cool factor with the huge inlet housing. If you look on turbonetics.com you can see all the deminsions of the various exhaust and intake wheels, sort of interesting. You can see how dinky the t3 exhaust stuff really is. New Garrett 60-1 HIFI on ebay:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7910759441&category=33742&sspagename=WDVW

[grape]

that will bolt right on the Banks or GM exhaust manifold. About the b housing being more efficient than the s housing...hmmm :rolleyes:

[84 Convert]

I just have to ask the stupid question that either everybody but me knows the answer to or... unlike me they are afraid they might look stupid! What factors allow a 5.9L Cummins to spin a turbo faster than a 6.2L/6.5L will? At work I drive a Dodge with a Cummins fed by a WH1C, that motor REALLY does not like to see more than 2500 RPM. What about the fact that our V-8's will spin up to nearly 3500 RPM?

Just curious. I'm always interested in learning things that might save some heartache later!

Gregg

[grape]

stroke length alone determines rev range, no matter what engine it's in.

[84 Convert]

My question wasn't about rev range but rather why a turbo would spin faster on a cummins than a 6.2.

Gregg

[CareyWeber]

Originally posted by 84 Convert:
My question wasn't about rev range but rather why a turbo would spin faster on a cummins than a 6.2.

Gregg I don't know for sure but I think it's a function of how much fuel is being burned, and how free the exhaust is to leave the cylinders and the turbo (the 6.5TD turbos are small on the exhaust side).

Carey

[grape]

all things being equal, actually picking up the shaft speed of a turbo is based on the exhaust A/R. When I say the holset's like the dodges use like to be spun.....I was using the wrong terminology, they dont' move into their peak efficiency island untill well over 20 pounds of boost. Which if you look at a map on turbonetics website you will see that there are turbos' that move 35 lbs/min at a pressure ratio of 2-1. Then there are turbos that don't ever move 35 lbs/min, no matter how much boost you make. BOOST IS NOT CREATED EQUAL.