Holset Turbos, PART 7

[jshuman]

Can someone take a few measurements of the overall diameter of the compressor housing and turbine housing of their HX52. I need to know before I build my manifold as I have a feeling I will upgrade from the hx40 in the near future.

I know this was a few weeks back, but did you ever get the measurements you needed? I have my hx52 sitting on my desk getting ready to send Justin a pm about rebuilding it, and I can take any measurements you need.

 

[dsmmatt28]

Does anyone have a pic of a good radiused divider?

+1 for sure

 

[We're on Boost]

Why not take an electronic emissions air pump from a chevy blazer or any other vehicle for that matter and hook up the hoses to the valve cover to pull a vacuum on the system

well the real power will come from getting the rings to seal better. A vacuum pump on the crank case makes the piston rings seal against the cylinder walls better and leads to less compression "leakdown". Honda guys do this in all-out motors.

Jeepers this is a cool subject - lots of interesting reading when you Google on "piston ring flutter" or on "crankcase vacuum pumps".

 

[Pirrofab]

FYI for engine builders. Not sure if this has been done on dsms. There is a company called Total Seal They are in summit and jegs catalogs and feature a "gapless" piston ring design. Its essentially 2 rings per each ring land that the gaps are placed 180 degress of each other to make a complete seal to allow for the most minimum amount of blowby possible.

 

[dsm-onster]

Having no gap still doesn't present a higher pressure differential across the rings that a vacuum pump on the crank case provides. You get some losses right at the contact of the wall and ring.

 

[Pirrofab]

Bleeding silver, I ran 30psi on e85 this last season witha rewired walbro 255, -6 feed line from the filter, and 1000cc. IDC was low 90s. The feed line dropped IDC 12 percent alone. On stock cams I flowed 43lbs/min. Never checked the change when I put the 272s in.

Due to how it requires more e-85 then fuel to do the same work I would assume that with gas the IDC would be lower. Race fuel would further lower that. Not that it would lower it that significantly though. I still think I would be ok with 880's. I know this isn't really a Holset topic but I just figured I would ask the Holset users specifically as we seem to be our own little family and seem to have to do things a bit dfferent. ah damn. 880's or 1000's? I don't mind being on the limit of the injectors I just don't want to be short. I would love to push the holset 35 to full tilt.

 

[Black94DSM]

I'm trying to find any info on this holset part number. 3591015 Can somebody help me ?

 

[We're on Boost]

FYI for engine builders. Not sure if this has been done on dsms. There is a company called Total Seal They are in summit and jegs catalogs and feature a "gapless" piston ring design. Its essentially 2 rings per each ring land that the gaps are placed 180 degress of each other to make a complete seal to allow for the most minimum amount of blowby possible.

Total Seal does offer these rings for the DSM 1st gen, 2nd gen, and evo.
And holy cr*p, look at this:

Mitshubishi 4G63T Vacuum Pump Kit Galant, Eclipse, Eagle Talon, Plymouth Laser

Notice at the end of the page it says "The vacuum pump kit was developed to reduce windage and to allow in increase in horsepower by reducing oil contamination of the combustion chambers and to improve ring seal in highly modified 4G63T race engines." I've read enough of Greg Zucco's stuff to be pretty sure that when he says "highly modified" he probably means an engine that's been built with the gapless rings you are talking about, because he is very favorable about those rings.
He wrote a very interesting tech article called "The Pros and Cons of Racing Vacuum Pumps" where he says this: "I always run gapless rings in my own cars, and I know that if you do run a gapless ring package and low tension rings that vacuum pump really does help you. It's not necessary to run low tension rings with a vacuum pump, but you should see some horsepower benefits if you do." The better ring sealing is apparently due to more forceful contact between the ring and ring land, not the cyl wall. Gas ported piston ring grooves are what really rev up your ring to wall contact forces. But they get you apparently into another whole can of worms with increased wear rate and so forth. There is a lot of stuff going on here with all of this. I'm still reading that's for sure.

Moroso: "Vacuum will increase horsepower by allowing the use of low-tension compression and oil control rings. In which the use of reduces frictional horsepower losses, blow-by, intake charge contamination and aids in detonation prevention".

 

[Kevin TSI]

Hey guys I'm not quite sure where to put this and you DSM guys seem to be more knowledgeable with the holsets than people on other boards so i would rather post it here.

My friend and I are building a 383 stroker for a drag car we are making and the bottom end is built for boost. Compression is 8.5:1 and the engine should make around 375-400hp at the flywheel n/a. We talked about doing a big single but have also been throwing around the idea around of using twins. The bottom end is good to 1400hp but what do you feel our limitation will be with twin 60mm 6 blade hx-40's with 18cm hot sides. Also what do you think spool time would be like. It would be 3.1l of displacement per side. Planning on just tapering the divider of the hot side down but a true twin scroll for each side can be fabricated if need be. Trying to keep wastegate costs down. haha

Input would be great.

Thanks again and sorry for the placement of this question in the forums. haha

 

[MIdsm]

A local buddy of mine and I both flow exactly 54 lbs/min, calibrated, hes using a 1150's and I'm on 1600s, both on stock lines and a single 255 in tank. The ONLY difference is I have my banjo bolt removed and filter to rail line is -6 and a -6 fitting on the rail (the oem banjo bolt and rail fitting are huge bottle necks) and my pump is rewired and I'm at 75% IDC and hes at 95%

I don't want to offend you but that's like comparing apples to veal (not oranges). The upgrades do help as has been proven but there are just too many variables to compare the two setups. The only way to accurately show differences would be to tune an engine on an engine dyno with stock fuel line setup and then only change the fuel line and rewire the pump and re-tune the engine.

A big difference is 1600cc Vs. 1150cc injectors.

1600 x 0.75 = 1200

1150 x 0.95 = 1092.5

Of course with indicated IDC of 95% the actual IDC could be 100%.

 

[Pirrofab]

Total Seal does offer these rings for the DSM 1st gen, 2nd gen, and evo.
And holy cr*p, look at this:

Mitshubishi 4G63T Vacuum Pump Kit Galant, Eclipse, Eagle Talon, Plymouth Laser

Definatley sweet to see that a product like this was made and that someone found a useful spot for where the a/c compressor sits because really, How many of us still have fuctioning a/c? . Downfall to this is that its race only though due to the crank pulley design even though our motors are internally balanced from the factory I still wouldn't trust it on the street. Plus since its belt driven its winds up robbing horserpower even though the amount is so minimal.

Seeing this motivates me to make a smaller, ligther, CHEAPER (cause were dsmers) version of this. It wouldn't even have to work all the time. Or maybe a low/high speed switch for everyday driving and then track use. This would also be another way to patch up the issue of dipsticks that pop out under boost from excessive crankcase pressure.

 

[We're on Boost]

Downfall to this is that its race only though due to the crank pulley design even though our motors are internally balanced from the factory I still wouldn't trust it on the street.

Yeah, when I read that I was kinda dissapointed because I am not ready to remove that piece from my car. Maybe I have the wrong idea but isn't that piece the "harmonic balancer" or "torsional vibration damper"?

Seeing this motivates me to make a smaller, ligther, CHEAPER (cause were dsmers) version of this. It wouldn't even have to work all the time. Or maybe a low/high speed switch for everyday driving and then track use. This would also be another way to patch up the issue of dipsticks that pop out under boost from excessive crankcase pressure.

Yes it definitely could be smaller because these GZ units are designed to pull up to about 15"hg vacuum and quite a bit of CFM, in fact you need to run like a vacuum regulator with them to keep the vacuum from going too high.


The best info I could find on the GM electric pumps, which only pull about 2"hg of vacuum, is in a TurboBuick thread here:

http://www.turbobuick.com/forums/general-turbo-buick-tech/234420-crankcase-evacuation-lt1-smog-pump-how.html

This thread is still running after about 2 years. It has pics, part numbers, user experience, yay and nay opinions, claimed benefits,, most of what you need to know. Strangely I didn't notice one word about turbo oil drain problems, which is what got us started here. Their issues are mostly oil leaks from various places blowing oil all over the engine compartment.

There is a RaceTronix page that has some very good info and pictures of the pumps w part numbers. They make and sell wiring harnesses for these pumps. The harness includes a Hobbs switch to turn the pump on only when you are boosting. Also includes a relay to power the pump, and the right plugs on the ends to make a plug and play install, pretty much. Page is here:

http://www.racetronix.com/product/RX-CEPH/RX-CEPH.html

These GM electric pumps seem like the way to go for a simple low cost install, if you are mainly just trying to reduce oil leaks and improve turbo oil drain. They do of course have their little problems. They don't like oil for one thing, and they don't last forever even if the air they are getting is dry. I'm not sure but I think they are basically a positive displacement type pump. So when they aren't running they pretty much block air flow. I'm still thinking about that one. If the pump fails while you are doing a pull, where is the crankcase pressure going to go? And when you are at idle or any low load operation you want the intake manifold vacuum to be pulling air through the pcv valve to ventilate the crankcase, right? Don't know if the pump, which would be off then, would let air in. If it turned out that these pumps are just a little blower (like the impeller in a vacuum cleaner), then it would be ok, air would go through them just fine in either direction when they are not running.

 

[Pirrofab]

Yeah, when I read that I was kinda dissapointed because I am not ready to remove that piece from my car. Maybe I have the wrong idea but isn't that piece the "harmonic balancer" or "torsional vibration damper"?




Yes it definitely could be smaller because these GZ units are designed to pull up to about 15"hg vacuum and quite a bit of CFM, in fact you need to run like a vacuum regulator with them to keep the vacuum from going too high.


The best info I could find on the GM electric pumps, which only pull about 2"hg of vacuum, is in a TurboBuick thread here:

Crankcase Evacuation with the LT1 smog pump. How To: - TurboBuick.Com

This thread is still running after about 2 years. It has pics, part numbers, user experience, yay and nay opinions, claimed benefits,, most of what you need to know. Strangely I didn't notice one word about turbo oil drain problems, which is what got us started here. Their issues are mostly oil leaks from various places blowing oil all over the engine compartment.

Yes that is the harmonic balancer and even though are engines are internally balanced I still wouldn't run without one. Well if they only produce about 2"hg then maybe it would be wise to see how much vaccum is seen from the factory pcv system line from the valve cover to the intake pipe pre turbo. Under boost the pcv valce is supose to be closed sealing of boost from entering the valve cover therefore creating a suction on the line that runs from valve cover to the inake pipe. If its more then 2"hg then we would need a bigger electric pump to see any gains from this.

 

[jrohner]

You can just run a pipe out of the exhaust at an angle and hook it up to the valve cover. That creates vacuum. Racecars are sometimes set up this way.

 

[Pirrofab]

You can just run a pipe out of the exhaust at an angle and hook it up to the valve cover. That creates vacuum. Racecars are sometimes set up this way.

This works however you can't use a muffler on a system like this because of the backpressure the muffler produces in the exhaust actually back feds into the crankcase causing excessive blow-by. In a non muffled set up this works great!!!

 

[rampridersrider]

What if you cut about 1-1.5 inches from the center divider on the stock housing. I'm using an open manifold on the 12 cm divided housing and this setup just looks really inefficient. It looks like there would be a LOT of turbulence inside the manifold collector.

I was thinking of perfectly matching the manifold outlet to the turbine inlet with some port work, and also removing around an inch or so of the divider down into the housing and then radiusing it and smoothing it all out. I think by doing this it will help a LOT with flow and there should be a lot less turbulence in the manifold collector.

Does anybody follow me on this?

 

[Gstclipse69]

Yea I follow you, I was thinking along the same lines as you. Port the housing to match the open t3 manifold and radius the divider quite a bit. As it is now bolted up it does seem like it would create a lot of turbulence. I would like some other opinions as well.

 

[DraginX]

I know this was a few weeks back, but did you ever get the measurements you needed? I have my hx52 sitting on my desk getting ready to send Justin a pm about rebuilding it, and I can take any measurements you need.

Please do, I haven't found them yet.

 

[joyfil2001]

Just want to put this out there. Out of no where I developed a major exhaust leak under the hood. Come to find out that the bolt plug that goes in the where the wastegate arm should be on my external setup BEP housing was gone. The exhaust gas coming out of there melted my slim fan . So I brought it to Meineke and they welded it shut for me. Anyone else have any issues?

 

[dsm-onster]

I didn't.

 

[JusMX141]

Come to find out that the bolt plug that goes in the where the wastegate arm should be on my external setup BEP housing was gone.

Interesting. I normally always put two or three spot welds on the nut to make sure it doesn't come loose....either I forgot on your housing, or the nut came loose anyway.

 

[joyfil2001]

Interesting. I normally always put two or three spot welds on the nut to make sure it doesn't come loose....either I forgot on your housing, or the nut came loose anyway.

Shouldn't that be something BEP would have done?

 

[Pirrofab]

Shouldn't that be something BEP would have done?

My BEP housing was manufactured without that and its just smooth? Maybe I have a redesigned version since they weren't offering internal gate set ups when I purchased it?

Don't wanna get back off topic again with this evac set up but just figured I would post another suggestion about it here since we were talking about it. Another cheap alternative might be our old cruise control vacuum assemblies. I just took mine off the car since the cruise cable broke and noticed it was controlled by a vacuum motor. It seems to suck my thumb on the intake side of it pretty well but didn't seem to pull any vacuum on the pressure gasuge i had hooked up to it. Its pretty small and compact and only weighs 2-3 lbs. Being as it uses the wiring harness we could use the connectors without much modification. Maybe even just turn on the cruise switch when racing and that would turn on the "pump". Its already got a nifty mounting spot on the firewall right behind the intake. After this I suggest a seperate thread gets made if its not already started on crankcase evacuation systems

 

[joyfil2001]

Oh, and just FYI, even with that massive exhaust leak it still built 21psi no problem!

This turbo is amazing.

 

[JusMX141]

The bad news is while the nut fell off and went somewhere down below, the bolt is still in there somewhere....whether is passed straight into the exhaust or went backward since you don't have a flapper and went into the turbine housing (hopefully not), it had to gosomewhere.

Maybe you should pull the o2 housing to have a look.