Turbo upgrade experiment..poor results

[JLEONARD]

I think it took my truck back a step.

Here's what I did... Thru pay-it-forward I got a take-off H1C from an intercooled truck. Has some miles on it but no play and it spins nice. My thought pattern was to install it along with my 16 cm exhaust housing as an interim step to building a frankenturbo, since it has a bigger compressor wheel, larger intake, larger air outlet.

So I spent an hour or so doing some more polishing on the 16 cm housing in between making the swap. I think it came out pretty good.

Mounted it on the engine, and used a short silicone reducer hose to adapt it to the stock non I/C crossover tube.

Primed it with oil, spun it around several times, hooked up the oil feed, fired up the truck, let her warm up a bit and went for a test run.

Spoolup is waaaay slower... similar to how it was when I was running the stock 18. 5 cm exh housing.

I still get about the same black smoke, maybe a scoosh more before boost builds.

EGTs are UP

Cooldown time is UP

Overall drivability is worse.

Only thing I can say positively is that high end, over 65/70 or so feels a little stronger... maybe freer is a better term... . but I didn't need an improvment there.

Oh and it whistles more.



Anybody have any ideas other than put my baby H1C back on?



Right now my fuel screw is in 1 12/ turn from stock, fuel pin is at the max position, plastic washer has been shortened by about 1/3, I'm running Bully Dog +50 injectors as you can see in my sig.



Jay

 

[bgilbert]

Jay have you made up one of those Greenleaf boost leak detectors? I just bought the materials to make one, cost about $8. The parts list is in a previous TDR issue, its out in the garage now or I would give you issue number. I'm thinking you maybe losing boost between the silicone hose and oem crossover. . ?

 

[JLEONARD]

Bill, Yes I was thinking I need to check that. I don't recall seeing what you describe in the magazine, but I think I can figure a way to make one. I assume you pressurize into the turbo inlet? ie get a plug that fits into the air inlet hose and adapt air to it.

 

[swankmetal]

maybe see if you can find an intake horn from an intercooled truck too. i don't know if it would make a difference, but it seems like when the air comes out of the turbo and has to be compressed down, and then open back up, it wouldn't be doing you any good. leak test would be the place to start though.



dave

 

[bgilbert]

Issue 43 page 46 for the 'engine pressure tool'.

 

[JLEONARD]

Thanks Bill, but no gots. However I do have a piece of heavy wall 4 inch ID PVC I found this morning that fits the intake hose pretty well, so I'll make a short shopping list and go buy an end cap and some fittings and make up a rig.

 

[JLEONARD]

OK, here I go pulling a CB and running my own thread :-laf ... . but here's an update... .

Made up a test rig, but I made it plug into the end of the air inlet hose where it clamps to the air filter box... .

You outta see how that corregated intake hose stretches with 10 psi... . would make a pornqueen quiver...

Anyway, I managed to put about 20 psi into it before I chickened out... no leaks.

Made a couple of test runs, but then I decided to change to a different adapter hose with less reduction and changed the way I clamped it.

Much better... Still has a scoosh more lag , and at lower rpm EGTs are up a bit from what they were with the baby turbo.

Runs nice at 65 to 85 with EGTs possible a bit lower... . the engine definately has less drive pressure.

But now, and this is why I think I have no leaks, I get the dreaded boost/turbo flutter/huffing ... . mainly in 5th with the pedal mashed, starting at about 1700 rpm/22 psi thru to 30 psi until the rpm gets to maybe 2100.

And it will happen anytime during that rpm range in 5th when I mash the pedal enough to get those boost numbers. Stops if I let off a bit to drop the boost.

Not sure I care for that.

Is there a cure other than a wastegated housing? If not I may put the baby back on for a while.

Anybody?

Jay

 

[Greenleaf]

Exaggerated cause you have a 5 speed (manual) transmission. A 14 w/g or non w/g would be the ticket cause of the transmission and the fact you desire drivability in favor of top end grunt/towing. More fuel to the nozzels and adjusting the star wheel up would be your only ticket out now... short of swapping turbo once again.



I know this guy who builds these "Greeleaf Pumps"... whatever they are.





Scott

 

[bgilbert]

Used the soapy water spray bottle to detect leaks yes? Before you put the child back on, run with it awhile see how you like it, see how it performs under different situations etc, you might like it. Then time for more fuel, Greenleaf pump, gsk, twins, studs, intercooler, DD clutch, 6 speed, .....

 

[JLEONARD]

soapy water spray bottle to detect leaks yes

No... it held pressure steady. If there's a leak, it's insignificant... I can still bury the 30 psi boost gage without much trouble.

I'll leave it on for a few days, maybe a week and see how/if I like it.

Like GL said, I am looking more for the driveability than for hauling/towing, so perhaps it's not the right setup for me.

I'm not sure if more fuel is the answer as that would increase the tendancy for flutter... no? But I suppose a 14 cm housing might spin quicker and burn the low end fuel.

I might try cranking the starwheel up tomorrow as GL suggested... that would be a good lunchtime parking lot project. The drive home is normally my "proving grounds"... . there are some nice hills for bonzai runs

Thanks for the input and any additional thoughts/ideas/viewpoints are welcome.

Jay

 

[matches]

Jay, glad to hear my old trubo is back in action. I'm very pleased with my current set up, the PDRhx35 ans 16 cm perform really well for my needs. I tow moderatly heavy and have yet to max out egts. Just break down and upgrade the turbo, you won't regret it.

 

[swankmetal]

if you've got access to a lathe or a machinist, cut a mwe slot in the thing. super easy and will get rid of the flutter AND make that sucker scream. btw, a smaller housing will only make the problem worse. much better drivability though.



dave

 

[bgilbert]

Well first off, lag is in the eye of the owner. Some may feel like there's too much, some may feel its just right. If you want INSTANT spool get a hy35-9 or 12cm housing. Course nonIC, egt's would get high and top end would be choked. I didn't like the top end difference I felt I lost from the 18. 5 to the 16cm housing. I have no plans of going any smaller than the 16. Now if I can just get my 'cracked' 18. 5 back from GL . Also time you get yourself a bigger boost gauge. Keep that 30 for a fuel pressure gauge. I'd get at least a 50 or 60psi boost gauge. Have you cut your fuel pin? That will gain you some throttle response. Starwheel up high or lean seems to me to slow the throttle response, but is good for holding back the smoke signals.

 

[JLEONARD]

Yup Matches, the old turbo is still pumping out some air... thanks again.

lag is in the eye of the owner

Bill you are right in that... (more like in the butt of the owner... . LOL).

I would say that with the baby H1 I had instant spoolup... even in 5th at 35 mph I'd get boost quickly. Now I have to be probably 45 mph to start spooling.

But the truck does run better at 70 plus... I had to keep looking at the speedo this morning and let off. At 85 she was feeling strong and still wanted to run.



Swank I do have a housing from a WH1C that has the MWE slot... I may put that on and give it a try.



EDIT... UPDATE. . I put the WH1C housing on after work and made a quick test run..... I think I'm now flutterless!!

 

[REakin]

Pardon my ignorance, What's a "MWE slot?" I tried a search and only came back up with this thread.



Rob

 

[BPonci]

Map width enhacement.

 

[JLEONARD]

What's a "MWE slot

Map Width Enhancement

It is a groove (I used slot incorrectly above) cut into the inside of the compressor housing that "enhances" or widens the compressor efficiency range called the "compressor map".

Now don't ask me how it does this, I'm not into the theory that deep.

In my case it acts as a relief to keep the copmpressor from stalling.

 

[REakin]

Cool! I've had the fluttering ever since putting the engine in my truck, thought it was the wastaged housing being stupid! Didn't replace the turbo during the engine rebuild due to the added cost, now I'm affraid to drive the truck because the turbo's so loose..... Any how, the turbo's off. Anybody know where to find the specs for the groove. Have a buddy in a machine shop take care of it for me if anyone could say. Thanks!! As always the TDR is a fantastic help!!



Rob

 

[bgilbert]

Jay when we gonna see pics of this setup? I'm sure you'd like to put GL in his place with your shiney motor .

 

[JLEONARD]

LOL Bill. No shine to my motor... it's all typical New England salty road corrosion everyday driver looking. :-laf

The turbo "plumbing" and the word plumbing is a stretch (pun intended) is similar looking to DPucket's right now.

I'll be working on a 3 inch crossover tube soon and I am expecting that will improve performace.