I'm just currious as to what happens when you try and force more air through a turbo charger outside it's effecieny level. Does it just take more horsepower to do it or does it heat up the compressed side more? both?
What happens if I have an engine big enough to move 550hp(~55 LB/min) at 8psi(roughly 1.5 on the scale) using this compressor? This would not be the ideal turbocharger for the application, but what if it was used anyways. What would be the downside of doing this?
It will go into choke. Choke is the extreme right side of the map. the compressor cannot supply you with the flow at the requested boost level so compressor speed rapidly rises (as do intake temps) until either detonation takes you or the wheel explodes. That is the most extreme case, a little into choke isn't ok, but it's not really gonna compromise anything. Deep into choke and you get the above. Go to http://www.Turbobygarrett.com They have alotta info in the tech section of the catalog.
Will it still choke if you are under the maximum flow of the compressor?? Or should I say will the choke kill it if it is still under the maximum flow of the compressor?
I would think increasing the amount of boost would help, but then you also increase the amount of airflow needed. Is there a way around this besides buying a new turbo.
MN... your going to need to get a turbo that will not go into choke.. you can bleed some pressure off the exhaust side wheel with a large enough wastegate, but once the exhaust pressure builds to a point where it outflows the gate, it will continue to overspeed the compressor wheel.. is this for your car? is this the turbo you had before? you considering going back to the ole turbo setup? im right there with ya.. i have been looking at this motor and the procharger and the motor and the turbo on the shelf... its mind boggling!
if its any help, the guys on the F-body forums are running single T66 or T76 hairdryers with some very impressive results! I am considering going to a T66 ballbearing wheel and a mid mount behind the passengerside seat with some modification to the rear hatch area for some extra room. would be pretty stealth.. i am shooting for a conservative 550-600 rwhp. not gonna get too greedy just want something different and can't get turbos out of my head!
Yeah, that turbo stuff is back in my head. I re-examined my turbo header and noticed at three of the exhaust ports that there was carbon build up in one direction or another, ie exhaust leaks. So I'm going to get the header plate milled down flat. It looks like it got warped when it was welded up. I'm also going to build a cross over pipe. I picked up a welder from Home Depot the other day, its back ordered now, but when I get it I'll start practicing.
I was hoping that the turbo would be ok for a little while. And I think I'll still use it and just limit my rpm and I should be ok. I've been looking and I also think that there is enough room to put a T series in there, but I won't be sure until I get the pipes built in there. But a little clue, all the T66 through T72 turbos cost the same from turbonetics, or who ever you get them from. So, step up that bigger compressor, the maps show it'll have better airflow at low boost.
If you've got some links to the f-body turbos that I could check out that would be cool, it's always nice to see what other people have done so I don't have to re-invent the wheel.
check out the forced induction section here and on LS1Tech, they both have some very experienceced radicals on there that like to be different "turbos" for power adders. with some luck and some time i am sure that this forced induction section on thevette forum will be filled with more people to assist in the projects builds.. right now i am VERY thankful for the few brave who have dived in head first! good luck and if i can be of any assistance let me know!
here is a map of what my modded engine would be close to with the 62-1 let me know what you guys think! this is a 355 8.7:1 CR, ported heads, turbo cam, and max of 14 psi boost.
Thanks for the links. My 396 with no intercooler should be ok at 8 psi and 5500 rpm according to what smokeemup says. but if I get the new heads and an intercooler I somehow doubt that turbo will still work. Atleast it should give me some nice midrange torque :D I guess we try it and see what happens.
with a set of ported heads and intake yada yada yada.. you will be changing your volumetric efficiency.. so try putting in something closer to 90-95% in this category. this should show some change in where it plots your points across the compressor map.. usually will be a bad thing if your borderline already. give it a shot....
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Turbo efficiency question
