Turbine size & trim

[brewmeister7]

I've been going through my turbo stash trying to determine if any of them are of the 82' or 83' variety with the smaller turbine.All the compressors are stamped A/R.42 but not all of the turbines are stamped or marked with anything I can decipher.How can I measure or find out otherwise whether I have A/R.82 or A/R.63?By the way,what does A/R stand for anyway? duh.Can you replace a center cartridge on a .82 turbo with one from a .63 turbo and leave everything else the same and get the desired results or are these totally different animals?

 

[Turbo-Rich]

Originally posted by brewmeister7
?By the way,what does A/R stand for anyway?

Air Research

 

[Turbo-Rich]

Originally posted by brewmeister7
How can I measure or find out otherwise whether I have A/R.82 or A/R.63?

Can you replace a center cartridge on a .82 turbo with one from a .63 turbo and leave everything else the same and get the desired results or are these totally different animals?

I'm pretty sure you would need the smaller housing. Someone else can verify this maybe, as I'm not 100% possative?

Sorry, I'm not sure how to tell the tubines apart. I have an .82 & a .63. I'll go take a look at 'em & see if I can visually see any determining difference.

 

[brewmeister7]

Thanks,
Seeing that Air Research is plastered all over the housings.I didn't think they needed to throw in an A/R too.Some people have referred to .82 & .63 as A/R ratios.Which is why I thought the letters might have another meaning.Let me know about the housings if you find anything.Appreciate it.....

 

[Turbo-Rich]

Re: Re: Turbine size & trim

Originally posted by Turbo-Rich


Sorry, I'm not sure how to tell the tubines apart. I have an .82 & a .63. I'll go take a look at 'em & see if I can visually see any determining difference.

The only diff. I can see right off is where the oil line goes into the center. On all 3 of my '83 turbo's, there are threaded holes on both sides of where the oil line goes in. The turbo with the .82 housing doesn't have these threaded holes. I know that's not much help but that's all I can see.

 

[Turbo-Rich]

Originally posted by brewmeister7
Thanks,
Seeing that Air Research is plastered all over the housings.I didn't think they needed to throw in an A/R too.Some people have referred to .82 & .63 as A/R ratios.Which is why I thought the letters might have another meaning.

Hmmm, I never considered it being anything but Air Research.
You might have something there. I was just throwing in my .02 cents. Someone here should know this one for sure.
Anyone

 

[pat83t]

Re: Re: Turbine size & trim

Originally posted by Turbo-Rich


Air Research

Actually, no. According to HPBooks #49 (turbochargers) a=nozzle area and r=distance from the center of the turbine to the centroid of area a. "The thing that is important to the user is to know the A/R. If he has a turbocharger withe a turbine housing A/R 0.7 and he wants to run his turbocharger slower, he knows that a turbine housing designed to fit his same turbine wheel with an A/R of 0.9 will definitely cause his turbocharger to run slower. On the other hand if he wants to run faster, he knows a turbine housing with an A/R of 0.6 or 0.5 will cause the turbocharger to run faster and give more boost." So there you go. I hope that helps.

 

[b4black]

When I put together this page on Buick Turbochargers , I learned that ALL 1979-1983 Buick Turbos use the same CHRA (or certer section or cartridge). So this menas that the 0.63 and 0.82 turbine housings will interchange. The smaller the A/R ratio, the "tighter" the scroll.

The 0.82 A/R housing has the number stamped inside the inlet. The 0.63 has it cast into the outside (near the oil feed line).

Also, look at the boss on the top that the turbine where the topmost elbow bolt goes into. If it is rounded, it's a 0.82. If it is squared off, it's a 0.63.

The smaller A/R will spool quicker. At very high RPM's it could run out of breath, but that's way above our useful RPM's anyway. I believe the 0.63 is the best choice for all applications on a Carb/Turbo.

All compressor housings are basically the same. A/R 0.42.

 

[brewmeister7]

Good stuff fellas....Thanks for the help....Rich,the bolthole theory seems correct but the markings seem to be inconsistent.I have units with A/R on .82 on the housing but not inside the inlet and I have units with no A/R stamped ANYWHERE.Theres some jibberish stampings(ACC24,M3) that don't seem to make any sense.These are all rebuilt units.Don't think that should make a difference though.Man,You think they did this crap just to make things difficult on purpose or what? Thanks again.

 

[Turbo-Rich]

Originally posted by brewmeister7
Rich,the bolthole theory seems correct but the markings seem to be inconsistent.
Eh, that was just my best guess anyway. At least it got ppl responding to your post

.Man,You think they did this crap just to make things difficult on purpose or what? Thanks again.

LMAO