Home-Built Twins

[michaelmurray]

Well, it's been 7 months since I first built and installed my twin turbo system. I'm happy to say I'm as satisfied today as I was when I first tested it. No problems whatsoever. I am using the stock HX35/12cm2 turbo as the primary and a HX40/16cm2 as the secondary turbo. This system may not have the high hp from 2500 rpm up, but has a great power band from 1300 rpm to 2800 rpm. EGTs cruising down the highway are 500* and 12 psi boost. I can hit 50 psi boost within 2 seconds. Temps never exceed 1300* with RV injectors and TST Competition box set on 8. The HX35's wastegate is set to open at @ 30 psi, which is about the time the HX40 begins contributing to the system. If the wastegate is set lower, the boost will level out until the rpm increases and the HX40 kicks in. I love it! It cost me ~$400 to build considering I already had the stock turbo and the HX40 turbo from a previous endeavor. For those out there that say this won't work are incorrect. Drivability is awesome. This is a stump puller's system, not a high revving-high hp system. Plus it's cheap. Hope you like it.



Michael

 

[michaelmurray]

Another view...

 

[michaelmurray]

...

 

[michaelmurray]

stacked turbos...

 

[michaelmurray]

top view...

 

[TxDieselKid]

Michael,

Welcome to the forums. Nice set up you got there.



I think you missed the point of "us" who say it wont work. Take off that HX40, and put on a H2E. Then I think it would be a different story. Member DRB has tried a setup much like yours and loved it. Read it here.



Hope to see you stick around,

Andrew

 

[michaelmurray]

Thanks TXDieselKid. Actually, I had been a member of TDR from Oct 99 until last december, but never renewed my subscription. I'm was the one asking the questions in your attached post (DieselPuff).



Anyway, what I'd really like to do is put the 12cm2 housing from the HX35 onto the HX40 and use that turbo as my primary. I would wastegate it to around 30 psi as well. (I understand that people didn't have good luck with the Kwikspool HX40-12, but I think they were running them at much higher boost than 30 psi. )For the secondary turbo, I would like the H2E/17cm2 from Pius. However, I don't want to spend the time and money at this time.



This system is working fine for what I do... daily driver. The drivability is like using the stock turbo, but without the high egts and with higher boost. I think there are many people out there that want "towing" power and drivabiltiy, at the expense of excessively high horsepower and turbo lag. That is me anyway.



Later.

 

[Evan A. Beck]

Cool setup... Are you the old 'MichaelT' that disappeared a while ago? If so, welcome back! Your truck looked pretty good before, with the custom rear bumer and 19. 5" rims.

 

[TxDieselKid]

welcome back....

Originally posted by michaelmurray

I think there are many people out there that want "towing" power and drivabiltiy, at the expense of excessively high horsepower and turbo lag. That is me anyway.



Later.

I do think there is a market for this type of system for the folks who tow, or do not want any lag on the daily drive.



Your idea for the next system sounds even funner. I wonder how it would be if you used Piers's Hx35, and HX40. He has several exhaust housings for both.



I just want the plumbing!!Oo.



Andrew

 

[JHansen]

Very nice looking setup! Wish I could fab like that... . I'd have me a set too! Maybe in my next life-either that or a good excuse to take up welding



Cool job man!

Jason

 

[michaelmurray]

Just thought I'd let you all know how I made it...



The hardest part was the exhaust elbow. You could have a machine shop make the flanges (or buy them at Turbonetics.com) and weld them to a 2-1/4" schedule 40 90* pipe. The cold side is even easier. It's made from 3" pipe pieces cut and welded together. I used a 3"-4" reducer at the HX35 compressor inlet. I initially taped the pipes together after I cut them with a chop saw(simulated a weld), then took the taped assembly to a friend to weld. I used part of my HX40 downpipe I bought from BD (2. 5 yrs ago) to create my current downpipe. I bought the oil drain plug at Cummins, took out the freeze plug in the block, and used the rear oil return port in the block for the HX40. I went to a hydraulic hose shop to build me an oil supply hose. For the air filter intake, I ordered from McMasterCarr.com the 4" hose. For the oil drain hose, I ordered from McMasterCarr.com and bought 7/8" hose. That's about it. Took about 2 wks working from my garage and fabricating the parts at work over several evenings. Remember, you don't have to do any fabrication yourself if you supply a machine shop some sketches. Hiring the work out could cost a few more hundred dollars. Good luck!



Michael

 

[Cummins Corvette]

That is just friggin' sweet dude!! Good job!

 

[Johnboy3]

That's a sweet set up. I really admire guys who head out into the garage with an idea and build something like you did.



Also thanks for the link www.mcmaster.com I found lots of good stuff on there I can use.

 

[DHRA]

I ran the H2E as the big turbo for a year and a half. I tried both the HX35 and the HX40 as the secondary. I think the HX40/12 combo dumping at 25 psi would be awesome! Good luck and like others have said, it's really respectable when you do your own.

 

[John]

Evan, that's got to be him! It's nice to hear from some of the original website members!



Hey Michael, NICE twin setup!

:--)

 

[Diesel Freak]

good job... looks like everyone will be building twins soon.

 

[TxDieselKid]

Originally posted by Johnboy3

Also thanks for the link www.mcmaster.com I found lots of good stuff on there I can use.

How long does it take to scan that site though. Man alive it's HUGE!!!



Andrew

 

[Extreme1]

Originally posted by TxDieselKid





How long does it take to scan that site though. Man alive it's HUGE!!!



Andrew

We use a lot of their stuff at work, you should see the paper catalog!

 

[Jim Fulmer]

Micheal Murray, were in Oklahoma do you live? I live in Newcastle, SW of OKC on I-44. I'll be back in town next weekend, right now I'm in Portland Oregon. I'd love to look at you setup and we have a Dyno Session planned in Lewisville Tx. soon.



Jim

 

[michaelmurray]

Update!

It's been 13 months now, and I have not had a single problem with my twin turbo setup. I love it!. Sure, if I wanted to spend more money I would have bought a different turbo, but I was playing with what I had. Never an EGT problem.