a friend was cleaning out his shop in an effort to lay some of his crap on me he gave me three items of interest. (not crap not crap not crap)

1) a set of cast aluminum edelbrock valvecovers, but...they have all 4 of the filler/vent holes drilled.

2) a brand new crower solid roller cam (only three passes on it). Although I intended going solid roller on my destroked 400 Im not sure about this cam, I dont have the cam card yet but I know two things. Its huge and its got a 110 lobe center. Maybe it wouldnt be so bad considering my plans for a very cranked P-1sc and nitrous.

3) and last but not least, a turbo he calls a "GM 5", taken in good condition from his 1996 6.5L diesel GM when he replaced it with a "GM 8". I am unfamiliar to these designations but the turbo seems to be a nice unit, larger than a T4, close to a smaller cummins or power stroke turbo manufactured by Borg Warner. It has the wastegate and down manifold on it, and an odd wastegate diaphram which has no spring in it, which he tells me is "vacuum operated", Im just quoting him on these this so bear with me.

 

Talked to friend today he is stoked about the idea of putting this turbo on the old JYD car from my video (he bought it from me a while back). We figure if it makes as much HP as the 150 shot did (435 rear wheel) then its worth it to not need the nitrous anymore. Things to remember:

1) This is a way low rent project.

2) He already has EFI and DFI (old style)

3) The motor is a very old, worn, but hard to kill forged piston 355 we call "the timex"

4) We are going to have so much fun showing his naysaying dad and uncle that this will work!

5) this is 50% experiment and 49% fun and 1% insanity

We are hoping to start small with the boost and work our way up to see what she can do.

I was looking at powerstroke, and then cummins intercoolers, but now I really have my eye on one of these larger volvo ones.

I must say right now from the start before anything is built that I would never have attempted this without inspiration from looking at the layouts achieved through the hard work done by preston smith and guido on thier "higher rent" setups.

 

too lazy to take pictures myself I took these off ebay of identical units:

 

and here:

 

and finally here:

 

Awesome steals! What are the specs @ .050 on that solid roller cam? I might want it if you dont and would be willing to part with it.

 

he said the lift is similar to the one he is now running but he has got to get me the cam card. I have no doubt it is hug huge huge. some where around .625" to .650" lift with 1.5 rockers

 

lol that is sweet. I asked my friend about a solid roller cam he took out of his motor, his @.050 duration on it was 276/284, thats more than my advertised on my current cam lol. Anyways, lemme know if you dont want the cam and we can work something out .

 

A friend that worked on his car told me the duration is around 250/260 @ .050 and 630/627 lift w/1.5's

 

The rumor is (I haven’t confirmed it) that the GM 6.5 turbo diesels have very small turbos. I did a quick look around online and I couldn’t find any hp numbers for a 6.5 with the 5 or 8 IHI turbo, if you could come up with that you’d have some idea of what they were capable of. If they are large enough then they are fairly nice turbos… IHI built some good stuff, it’s just that most of what they’ve built was fairly small.

 

Cool, PM me if you decide you are willing to sell it .

 

Its a custom grind so I must get the cam card before anything happens to it. I also don't exactly know what we are going to do now either, I came across a "snag". I was doing some research trying to remember what the specs on the JYD's motor was and I looked up the piston and remembered the heads are 64cc. The pistons are the .100 dome 350 TRW pistons, on a .030 bore, w/64cc that is 10.6 (more likely 10.5 to 10.25) to 1

Now Im thinking, I have some 882's, hmm what to do-what to do? Im not sure if I want to change the heads or forget the turbo project temporarily.

 

does anyone have compressor maps of the "GM-5" turbo (see pics above)? Im trying to get an idea of how it compares to the powerstroke or cummins holset turbos as far as being a possible project part. Anyone have any idea what the A/R's on these are either?

 

the A/R rating should be on the housings. Take it apart, clean it up and then see if you can tell the what A/R Ratings are.

(The exaust one will probably ve very hard to read, if at all)

also, the Specific model of the turbo should be on the bearing housing on a little plate type thing.

 

If you find a compressor map for any of the GM_ turbos, or any of the other old IHI turbos (besides the new ones that you can easily find on their site) I'd appreciate if you posted them or sent me a copy...

 

my problem is this looks as big as the single we put on a cobra a few years back, but to me it looks smallish like maybe it would be more ideal as part of a twin setup for a BBC.

My brain is just having problems with the small exhaust inlet

I did see the set of poor charts on IHI's site but I dont have a positive way of know which is mine...

 

the only numbers are cast in and are as follows:

side of bearing housing is "53T-012" other side has a "6" and a "CP"
exhaust housing has a "237795" with the numbers "3G" and "l85" or "l8S" sideways but at the end of the longer string of #'s
the exhaust flange has "025T - 181"
the wastegate assembly is cast with a "045T-023"
the PN etched into the compressor outlet tag is "12552738" and the model # "GM 5"

 

Got a spec 5 huh?... I have a spec 3 going on my 240I6. I had a couple new take off's spec 8's, sold em on Ebray..

Good luck finding any info.. I've looked. Also tried thru contacts for info from GM... nada.

BW

 

yeah Ive only seen it called GM 3, GM 5, and GM 8 online so far, I wonder if they are the same as the RHF3, RHF5, and RHE8 offered by IHI now? The RHF models go 3,4,5,55,6 then they are the RHE and they go 61,62,7,8. Im not even sure what the RHF and RHE stand for but I really dont want to even get too envolved with a JYD tubo project if this damn thing wont work well.

Where did you get the name "spec"?

I guess the GM 3,5,and 8 were all used on the GM diesels, I have seen some forsale recently, maybe they were yours. I guess the guy I got the 5 from popped the 8 on his 96 and made it into a Pstroke eater (atleast back in 96 it might have been).

 

the tag should say P/N and Spec: GM-3,5,8

I sold mine a year ago.

From what I have seen, the 3's are rear intake mounted with dual exhaust inlets. As in it site on top of the intake manifold and both exhausts come up from each side.

The 5's are 90* on the exhaust outlets

The 8's are 45* ish on the exhaust.

Some differences in center sections to match changes to the compressor housings. I have seen rough cast and smooth like yours.

BTW the stock WG is vacuum controlled.. need to fab up a WG from a T3.

BW

 

I was very curious, whether the T3 wastegate solution I came up with would work thanks for your affirmation of it.

What do you think about the idea of this GM5 and a volvo intercooler (or some other cheap intercooler) on a mild forged piston 355? too small for boost? too small for exhaust? it will be just a single setup. I would love to make 8 to 12 psi with it.

 

Well I'm adapting a GM-3 to a 240 I6 Ford with FI and a 749. But thats along term project.. Got the Bu to finish first.. then the truck.

Really it's a guess as to what it will work on. Might be a tad small for a 355, but what the hell give it a shot. I am..

BW

 

I believe in fate, I figure there are two things going for me, first I got it for free and I believe in fate, it would never have come into my possetion if it wasnt meant to be, maybe the bigger turbos I was looking at would have been too large?

the other is that once it is built, if it turns out to be too small but shows its viability, then I can always just get another turbo, change the flanges and put it in its place?