AR ratios?

[Tony]

Does anyone know the stock AR ratios (both hot and cold sides) for the t3 on the SVOs? Looking to replace my turbo soon and need this info so that I can get the correct size. Thanks....

Tony

[svono50]

If my memory serves me right, the compressor side is .6 and the turbine side is .48. I can check what is cast into my stock turbo at home if someone else can't confirm the info.

If your turbo needs to be replaced, I would think about upgrading while you are at it. Just a thought.

[SvoTy]

The 84's and I am pretty sure the early 85's have .63 exhaust housings.

[Tony]

Yup... I'm kinda thinking of goint to a T3/T4, or a Super 60 eventually. Any thoughts? (You see my list of mods...) I think upgradeing is a good idea, as long as I'm at it, but I don't want to put too much turbo on it. I'm looking for around 250-275 WHP. Just moderate mods, nothing too radical. This is my daily driver for now, and reliability is key... I think I can likely come close to that with the stock turbo, as I understand it. (Though an upgrade and the stock unit cost roughly the same... Don't know....) Any feedback is appreciated!

[SVOeric]

84, 85 had .63

85.5, and 86 had .48

on the exhaust side

I'm not sure what's on the other side.

BTW: this info was in the FAQ section

[Tony]

Thanks for the info!

I searched the borad for "AR ratio" and it indicated that "AR" was too short a term to search... I needed at least 3 characters. Searched for "A/R ratio" and came up empty. (Not sure if that search included just the "engines" section, or if it included the entire board, including the FAQ. Anyway, I always try to locate answers in the archives before I post a Q..... Just so ya' know....

Thanks again for the info!

Tony

[SVOeric]

By default .. the search searches everything, unless you change it.

a/r or ar would not have found it anyway.. it is listed under turbo trim



also

just a note, I didn't say this before, but the difference between a t3 and t4 is the compressor side of the turbo. that is why it is a
T3 with a .63
or
T4 with a .63
or
a hybrid (often a T3 housing, with a T4 compressor wheel with a .63.

ok.. I think i am making sense

[svono50]

Tony, With a stocker turbo you could reach your goal, but you would be in the upper limits of the efficiency range for it. A Super 60 would get you there, but is HP limited as well. If you would like a turbo that you could grow with a T3/T4 hybrid is a pretty good choice.

I just installed a Turbonetics hybrid with a 46 trim compressor and a .63/Stage II turbine unit. This turbo can push up to 350hp, but can easily live with lower numbers. This unit has good manners on the street and while it does spool up a bit slower it has excellent top end push when combined with a "Gillis" boost valve. Enough so that I uncovered a weak clutch that now slips when I push it in 3rd or 4th gear...doh! I might as well upgrade the ol' flywheel while I am there, darn!

If you wanted a high HP turbo I have seen good results with a 54 trim comp and a .63/Stage III turbine, which can support 400-450hp. This was out of the range of my current motor combo, but may be an option if I ever upgrade my combo.

[Tony]

Eric,

Thanks for the input! That's kinda' the way I was leaning anyway. That makes a lot of sense. I'm saying 250-275 WHP now, but who knows.... HP is adictive, and I'd hate to have to re-invest in another turbo later. Especially if the hybrid has that much flexability. (Good manners at the lower #s). I hope to get the car off the "daily driver" duty within the next year or so. I may think of some more creative ways to do things after I get it off the road as a "full time" vehicle.

Thanks again...
Tony