Holset Turbos, PART 3

[JWoodley]

Sweet. I got my vband parts from Extremepsi. My summer project is going to be an external WG setup off the 02. Would you recommend a 38mm or larger?

 

[420a-t]

Here's some pics I took today. I finally got some wrench time in. Here's how I used a stock mitsu wastegate actuator with a holset...a lot cheeper than going external. I have a friend who has ran 26psi no problem with it setup like this.

 

[dsm-onster]

That wastegate actuator location is pretty cunning! He was able to hold boost down to 26psi? Most guys I've talked to say that the holset actuator springs are just too strong. Or the actuator body is just too small to keep boost under 30psi easily.

JWoodley, a 38mm wastegate should be just fine. Go bigger if you want to run under 20psi, IMHO. But, why would you want to do that non-sense ?

 

[IPT]

Go bigger if you want to run under 20psi, IMHO. But, why would you want to do that non-sense ?

. Tell that to a Honda guy..

 

[dsm-onster]

Oh, but they make so much more "HPs per psi" .

 

[JWoodley]

I went vband off of the compressor. I finished up my LICP today. Hooked up the laptop and played with DSMLink a bit. Tried to get the idle fuel trims adjusted.

 

[JWoodley]

She idled, but very, very lean. I've got it tracked down to a dead front 02, me not setting the MAF-T correctly, or maybe a crapped out injector(s). So once I get some troubleshooting out of the way I'll be getting pretty close to strapping her down on the rollers.

 

[Maglin]

Oh, but they make so much more "HPs per psi" .

 

[dsm-onster]

Let me rephrase. . . I love my dsm and I don't feel superior head flow is worth it for my budget. I'd rather reach a 400whp daily driver goal at under $2500. 25psi is much more boost, but a 400whp dsm has much more horsepower per pound of weight than a b18 civic with the same budget. Most of us really arn't thinking as big is you .

 

[420a-t]

Well, I drove my car last night, and the holset is laggy compared to an evo3, true story . I got on it a little, and I was able to make 8psi before 4k on half throttle, so that's a good start. Good to see there's boost before 4500rpm's. I'll probably go tune some more tommorow.

 

[Larry L]

Has anyone had problems with boost creeping. I had a dyno session done this weekend aftrer upgrading my intercooler to a considerably larget unit and my HX-35 want to be at 26psi no matter what. Even on the 1 bar spring it creeps to 26 by redline. Please help

 

[dsm-onster]

Well, I drove my car last night, and the holset is laggy compared to an evo3, true story . I got on it a little, and I was able to make 8psi before 4k on half throttle, so that's a good start. Good to see there's boost before 4500rpm's. I'll probably go tune some more tommorow.

You have a turbo that can provide 13lbs/min more airflow than a evo3 16g . And The hx40/h1e turbine wheel is huge compared to a td05h and even the h1c/hx35 turbine. That hotside you have is proven to +600hp.

Whenever you can do this, tell us the boost threshold as you "floor it". Personally, I start at 2K in 3rd gear and go to 100% throttle to get a spool time. Are you using a bleeder valve or a ball-&-spring valve? Which wastegate actuator are you using? You've opted for an internal gate, right?

I'm pulling my head today to see how much I have to order to get her back on the road. I really want to post up some airflow logs to redline and at higher boost.

Has anyone had problems with boost creeping. I had a dyno session done this weekend aftrer upgrading my intercooler to a considerably larget unit and my HX-35 want to be at 26psi no matter what. Even on the 1 bar spring it creeps to 26 by redline. Please help

I've never heard of this. In fact, I've heard the opposite. The internally gated BEP housings blow open their 38mm internal gate. The gate could be hanging up. Is your boost controller plumbed correctly?

To determine if you have true boost creap caused by the turbine housing design, unhook the flapper arm completely from the actuator and see if you still can develop several psi boost by redline. Before you do this make sure your flapper flops almost wideopen with your hand moving it. My bep turbo-to-o2housing copper gasket didn't have the correct hole diameter and center for the bep housing. And my wastegate bumped the gasket. . . I still didn't get any creap in the small bep housing with my t3 stage3 turbine (quite similar to the hx35 turbine).

 

[Larry L]

I have a tial 38mm external wastegate with a 1 bar spring. We found the problem on a dyno. We disconnected the mbc, and it still over boosts

 

[JWoodley]

The internally gated BEP housings blow open their 38mm internal gate.

Any idea of what pressure this occurs at? I'll be getting my VCE and AEM UEGO installed this week and will get some numbers very, very soon.


I'll be dynoing FWD.....any recommendations on what HP level to shoot for in order to be at or above 400AWHP?

 

[dsm-onster]

Th awd drivetrain takes about 30 more horsepower than the FWD drivetrain. There is no percentage loss. It takes a definate amount of power to spin the AWD components and that doesn't change unless you change those components. I say shoot for 430hp and you should be good.

Any idea of what pressure this occurs at?

Since it is exhaust manifold pressure related, not intake manifold pressure related, it is VERY setup specific. With my these flow altering mods (ebay fmic, 2 1/4 inch shortroute piping, fp2x cams, evo3 exhst manifold, 3 inch exhaust, and 2g o2 housing, 3 inch metal intake with cold air inlet) my t3 stage 3 blew my wastegate open at 25 psi with my 60-1 compressor in the e-cover. Others with similar mods (save larger diameter intecooler piping) and a 50-trim compressor see it blow open at 20-22 psi.

On a brighter note, if an hx35/h1c turbine is not exhibiting this trait or showing the opposite (boost creep), then that turbine should be MUCH more efficient than the t3 stage 3 turbine. Too bad I'm not running an internally gated bep housing to compare the t3stage 3 to the h1c/hx35 turbine . But Larry L is. I've heard of more than 2 hx35s holding rock solid boost to redline internally gated with the same bep housing, same style fmic, an 272 cams with a coldair intake. So it seams that the hx35 turbine is at least as efficient and everyone's spool speeds seam to indicate that it is more efficient since that turbine has been pushed to 500whp.

 

[420a-t]

Well, I got a log tonight. I start to build boost at 3500-3700rpm. It hits hard only on 10psi too. I just used my tune from last year to see what I could do (and with a dead o2 sensor, mind you). I made 356hp (via dsmlink) at 6500rpm with 9.5psi (via gm 3-bar), with airflow at 26.2lbs/min (via stock maf). Last year when I was at the track I made 385hp (via dsmlink) with 26psi and race gas and spraying meth on my e316g!!! I am using a stock mitsu wastegate actiator off of a 14b and a ebay ball and spring type mbc.

I found that my boost gauge or my map is incorrect today. When my map said I was boosting 15psi, my gauge said 21psi, and my map says I have around 12inHg at idle whereas my gauge says I have 3inHg.

This has nothing to do with holsets, but my brakes are very spongy now. I've bled them 6 times and checked my vacuum lines including my brake booster line (it's on correctly). If anyone has any ideas, please PM me, it sucks making power only to find that you have to fred flinstone your stops.

 

[dsm-onster]

I have a tial 38mm external wastegate with a 1 bar spring. We found the problem on a dyno. We disconnected the mbc, and it still over boosts

So, have you unhooked the wastegate flapper arm completely from the actuator and see if you still can develop several psi boost by redline?

420a-t, does it feel as strong as with the evo3 turbo? The 26lb/min and 350hp doesn't exactly jive. Do you have a log you can post? The gauge is probably off. As 3inHg vacuum is not idle-worthy.

12inHg is still rather poor vacuum for idle with comp 100/200 cams. You SHOULD be at around 15-17inHg. Poor vacuum and spoungy brakes: check your brake vacuum line to the intake manifold. This could account for some of the slow spool speed. I don't know if a master cylinder going out can develop a vacuum leak. In fact, just run a boost leak test if you havn't yet.

 

[420a-t]

My car pulls hard on just ten pounds. As hard if not harder than my evo3 on 21psi. I dunno if it's because the lag makes the boost "jolt" me into thinking its a lot more, but I got going around nearly 60mph just outside of first gear (auto tranny).

Thanks for the help Matt. My gauge is an autometer cobalt. I did a boost leak test, and there was a couple be the throttlebody that I fixed, but nothing else that I could hear. I checked the vacuume line and it's fine, but why would all of the sudden my master cylinder go out? It worked fine before I tore my car apart, and it wasn't left dry either. Thanks for all the help. I'll get this turbo going like it should here soon!

 

[JWoodley]

My car pulls hard on just ten pounds. As hard if not harder than my evo3 on 21psi. I dunno if it's because the lag makes the boost "jolt" me into thinking its a lot more, but I got going around nearly 60mph just outside of first gear (auto tranny).

Thanks for the help Matt. My gauge is an autometer cobalt. I did a boost leak test, and there was a couple be the throttlebody that I fixed, but nothing else that I could hear. I checked the vacuume line and it's fine, but why would all of the sudden my master cylinder go out? It worked fine before I tore my car apart, and it wasn't left dry either. Thanks for all the help. I'll get this turbo going like it should here soon!

When are you hitting full boost RPM wise?

 

[Larry L]

Hey wiseman I am external...The internal flapper door has been removed completely, and the hole to the outside welded shut. Now the 38mm flapper hole is still open. BTW I have had this set up for 1 year with no problems. Just switched from a small fmic with 2 1/2 inlet/outlets to a huge fmic with 3 inch inlet/outlets could this be the problem?

 

[lo2210]

A little off topic but whats the hx55 equivalent with? I just got my hands on one. comp side 65mm exhaust 75mm. thanks

 

[projecTSI]

^^^That is a HUGE turbo. Are you planning on using it on the DSM?

 

[lo2210]

yeah I just found a thread on rx7club saying that it spools faster than the GT42.

 

[JWoodley]

^ Get rid of the silencer ring. You'll like the sound.

 

[Larry L]

You'll need 1000cc inj just to spool that monstrocity up...