Project "no buck" turbo...
 

Not exactly a 2000hp monster, but this might be of some interest to the budget readers...

The idea was to see how cheaply a turbo setup could be installed and how much power could be expected without breaking anything. All the work was done by students at the Blairsville, PA Wyotech campus. The results were pretty amazing... An article is due out in the Jan 2011 "Auto Enthusiast", but here's a quick summary.

What we are working with here is a 350 Chevy 4 bolt with cast crank, powder rods, 9:1 cast pistons (may be hypers), and Edelbrock e-tec 170 heads. Cam was a .501 / [email protected] 110 LSA hydraulic flat tappet. Basically Edelbrock's 360hp crate combo. The engine has Edelbrock Pro-Flo (Magneti Marelli) port injection with a 4bbl TB. The ECU was swapped for a FAST XFI stand alone, as the Edelbrock unit is not compatible with boosted engines.

N/A engine dyno baseline was 375hp / 360lb ft. We scrounged a Holset HX35 turbo that came off a Dodge Cummins pickup. The turbo was plumbed to a set of block hugger headers with a custom Y pipe. A Tial 38mm external wastegate was used, as the stock internal gate controller could not be adjusted to safe boost levels for a gas engine. The turbo was set up to blow through the TB with a Turbonetics carb hat. The 27lb/hr injectors were swapped for a set of 43s.

We decided to limit boost to 15psi, and crossed our fingers... . All pulls were made from 2500-6500 rpm.

After some tuning we ripped off a pull at 487hp /487lb ft. on 93 octane Citgo. Intake temps were getting out of hand, so we plumbed in a stock Dodge Cummins intercooler. That change (and some more fuel) netted a best pull of 527hp / 605lb ft. The best part: the turbo acted more like a supercharger, crossing into boost at 2000 rpm(!) and making 15psi throughout the pull range. The engine made over 500lb ft. all the way from 2500 to 6500 rpm.

The other best part: With some careful shopping, the turbo setup (less ECU) can be duplicated for just over $900 including all exhaust components AND an intercooler!

That's 150hp and 250lb ft. of useable power for less than a grand. Pretty good value I think!

http://www.camcojb.com/temp/2ekoqqu.jpg

Since we found another Holset HX35 laying in the parts room, we decided to see just what this stock bottom end will survive...we are going TWINS this time around, with dual 4bbl TBs on a tunnel ram (again it was laying around from a past project...). We also swapped the cam for something a little more turbo friendly. We installed a Comp grind with [email protected] and a 114 LSA. Lift dropped into the .460 range, so we are putting a set of 1.6 Comp rockers on to get back to just under .500. We will actually be putting the single turbo setup back on first to see how the 2 camshafts compare power-wise.

Well, we just did the pressure map for the HX35 on squirrelpf.com. Turns out it is a tad small for our application...but 2 of them are perfect...:thumbsup:

http://www.squirrelpf.com/turbocalc/...product_id=113

I resized it. Cool project! Normally I wouldn't recommend a diesel intercooler as many have found them too restrictive on higher powered builds; however it definitely helped at that power level.

Jody

Well, it's back on the dyno. We were going to run the cam in tonight, but things got kind of "interrupted"...:censored:

We are prepping a Dodge Magnum wagon for the small-block and a ZF 6 speed (hey, the V6 was blown up...:morepower ). The flanges and entry pipes for the twins are done, and both turbos checked out.

any new updates? :unibrow:

a microsquirt ecu should work perfect for that application if budget is an issue

Well, we swapped in a more "turbo-friendly" cam (went from 110 to 114 LSA and about 20deg less duration @.050). We also switched to the "other" Holset turbo that was laying in the parts room. The plan was to compare results with the original tests, just to verify the second turbo and check out the cam change. It didn't exactly work out that way.

Finally got back on the dyno after waiting for a couple weeks while the other class sorted out (and then blew up) a blown 355.

We chased a persistent misfire, swapped plugs and wires, and finally got some smooth pulls in. It was immediately obvious that something was different. The first turbo spooled fast, but this time the engine went into boost as soon as we'd crack the throttle under load.

We saw 505hp / 670lb ft (!) once, but couldn't back it up. After numerous problems, we made 3 consecutive pulls around 450hp / 510 lb ft and gave up. The engine was losing hp and boost above 4500 rpm, but the A/F ratios were right on the money. After pulling the engine off the dyno, I found the "problem".....:P

They say a picture is worth a thousand words...

Article on the original turbo setup is out in the Jan 2011 issue of Auto Enthusiast. Titled "Learning Curve". I don't know who Kevin Harper is, but he did a good job of rearranging a few words in the story I wrote... :clap:

congrats Ray.

Jody

Somethings different on the inside, I'm not sure what its called, Help me Jody I'm trying to learn about turbos,

I want to do a single on a 5.3 and put it in the Nova!

Just found this: http://editions.amospublishing.com/K...spx?d=20110101
It's the online version of the magazine. If you click on the cover it opens. Article starts on page 30.