Tried a T04E 50 trim/Stage III .48 ...

[Pat]

... and so far, I like it. The car is a '90 Shadow VNT that I bought. It has the original 2.2 bottom end and of course it's a 5 spd. The previous owner assembled the top end... FWD big valve head, 2 pc, TU header, FMIC, 3 bar FWD cal. The turbo that was on it was a T04E 50 trim/.63, F1-57 wheel (stage III).

Long story short, the turbo spooled very slow and honestly, was not that much fun to drive on the street. Once it was up above 4700 or so, it was a screamer, but for a street car it was not what I wanted. I would have left it alone for the time being, but the turbo was smoking. I debated putting a stock T-II on it, but I was really itching to try a .48 housing on a 50 trim and all the intercooler piping was already set up for a T04E housing, so I figured what the hell.

I pirated the 50 trim that I ran on my Shadow race car for all those years, disassembled it, slapped on a .48 stage III housing I scored a while back and put the car back together. So far, I like it. A lot. It spools extremely fast. If I hit the gas in 4th at 3k rpm, it's at 14 psi (where I have it set) by 3200. At low rpm, I'm building boost below 2k and it shoots up pretty fast once it's at 2500 or so. It pulls very hard through 6200 or so, then seems to drop off a bit, but still pulls hard. It does give up a little of the top end scream with the .48 housing, but area under the curve has certainly increased for the rpm range I want to run with this motor. Considering it's a stock bottom end, 115k mile motor that I'm not looking to rev to 7k. I am curious to know if surge will become an issue as the boost level goes up, but so far at 14-15 psi, no surge at all.

Eventually, this car is going to be returned to stock and this turbo will likely end up back on the T-III motor. It was just an experiment I wanted to try out. I'll will get it to the track before it comes apart though. Butt dyno says it's doing pretty good and it's definitly a ton more fun to drive around town. I know I'm sacrificing a bit of the compressors potential, but after reading some of the SRT guys impressions of a stage III/.48 housing 50 trim and seeing some dyno plots, wanted to give it a try.

I'll keep everyone updated as I tinker with it or when I get it to the track.

Pat

[shadow88]

Sounds like a great combo! I really think the .48 housing is being overlooked as a viable performance part.

[89scottytona]

That's pretty much what I'm running on my daytona now... Stage 3 exhaust wheel in a .48 housing, 50 trim t4 cold side in a machined stock t2 cover. Without the anti-lag (stock 2.5t1 cal) I have now I would have full boost by 3200 rpm on the factory tach. With it (3 bar cal from shelgame), 3k and its on like donkey kong... LOL the car is totally street friendly, almost like a stock turbo car. I haven't dyno'd the car as of yet, there are a couple more little things to work out... But if I had to do it again, i'd gone with a standard t4 cover, not with the machined stock cover.

[john1320]

I honestly can't see you running into surge, unless your waste gate is not up to task. 18psi and no surge on a stocker and big can..

[Pat]

Sounds like a great combo! I really think the .48 housing is being overlooked as a viable performance part.

I remember you went back to a .48...what are the rest of the details of turbo that you run?

That's pretty much what I'm running on my daytona now... Stage 3 exhaust wheel in a .48 housing, 50 trim t4 cold side in a machined stock t2 cover. Without the anti-lag (stock 2.5t1 cal) I have now I would have full boost by 3200 rpm on the factory tach. With it (3 bar cal from shelgame), 3k and its on like donkey kong... LOL the car is totally street friendly, almost like a stock turbo car. I haven't dyno'd the car as of yet, there are a couple more little things to work out... But if I had to do it again, i'd gone with a standard t4 cover, not with the machined stock cover.

So far, I'm liking it a lot. Turned the boost up a bit to 16 a little while ago and I like it even more. :-)

I honestly can't see you running into surge, unless your waste gate is not up to task. 18psi and no surge on a stocker and big can..

I was talking about compressor surge...if the engine is not able to ingest the volume the compressor is putting out. I suspect it could become an issue. You'll likely never have compressor surge on a stock turbo since it's such a small compressor. This t4 50 trim in a full t4 cover moves a ton more than the stocker.

[89scottytona]

Pat, my g-valve is set at 17psi... In first gear it spikes to 19psi and settles to 17. I'm sure if I hooked it up to the solenoid it would get rid of the spike as the cal was written for computer controlled boost. As for driving it around, like I said it feels like a stock car...until you mash it... I've been running this turbo for a combined time of 3 months. No issues driveability wise.

[Vigo]

Thanks for posting this up.. this is one of those combos that i think most people would be REALLY hesitant to try if it weren't for posts like this.

some of the SRT guys impressions of a stage III/.48 housing 50 trim and seeing some dyno plots,

If you have any of the links handy that'd be nice but dont go doing my work for me.. im just curious what the consensus was and what kind of numbers you were seeing?

[Ondonti]

I know someone who ran one on their srt-4 but it was up at high altitude so there were a lot of things going against it, especially the builder...

[turbovanman²]

I wanted to try this combo too but also never got around to it and with my wastegate setup, made it harder to try. Thanks for trying it.

[Pat]

Thanks for posting this up.. this is one of those combos that i think most people would be REALLY hesitant to try if it weren't for posts like this.




If you have any of the links handy that'd be nice but dont go doing my work for me.. im just curious what the consensus was and what kind of numbers you were seeing?

http://www.srtforums.com/forums/f70/...dyno-s-575385/


http://www.srtforums.com/forums/f24/...f-dyno-409314/

Here are a couple that I saw relatively quickly.

[Shadow]

Nice to know that this combo can work with the proper To4e cover. I think the problem with the brutal spool of the stage 3 .48 A/R combos was the fact that they came (I believe it was from FM?) with 40, 46 or 50 trim compressor wheels in machined out stock housings.

You shouldn't run into surge issues with a stage 3 wheel, but if your really seeing full spool by 3200rpm in 4th gear I'm thinking you might.

[Vigo]

Srtforums.. not my thing. lol. But i found the numbers and i am surprised.. The numbers are higher than i thought.

Thanks for the links.

And now that i think of it... Rattlesnake here dynod slightly over 400whp through one of our .48s... not sure what turbine he had in it.

[contraption22]

Very interesting. Very very interesting.

I'm curious about the backpressure numbers before and after the swap. But regardless of that, those numbers don't mean anything if you are enjoying the car more with the smaller housing vs the bigger one.

[turbovanman²]

Srtforums.. not my thing. lol. But i found the numbers and i am surprised.. The numbers are higher than i thought.

Thanks for the links.

And now that i think of it... Rattlesnake here dynod slightly over 400whp through one of our .48s... not sure what turbine he had in it.

Pretty sure he had a GT series turbo on his car, but my memory is going, lol.

---------- Post added at 10:31 AM ---------- Previous post was at 10:30 AM ----------

Nice to know that this combo can work with the proper To4e cover. I think the problem with the brutal spool of the stage 3 .48 A/R combos was the fact that they came (I believe it was from FM?) with 40, 46 or 50 trim compressor wheels in machined out stock housings.

You shouldn't run into surge issues with a stage 3 wheel, but if your really seeing full spool by 3200rpm in 4th gear I'm thinking you might.

That's wicked spool RPM, I am over 4000 rpm on both the 8 valve and TIII heads. Damn it, should have tried it on my old 8 valve setup, lol.

---------- Post added at 10:37 AM ---------- Previous post was at 10:31 AM ----------

http://www.srtforums.com/forums/f24/...f-dyno-409314/

Here are a couple that I saw relatively quickly.

Damn, nice numbers, and the area under the curve,

[Pat]

You shouldn't run into surge issues with a stage 3 wheel, but if your really seeing full spool by 3200rpm in 4th gear I'm thinking you might.

I think so to, it's just a matter of when. I turned it up to 16 psi and still no surge in the low 3000's. Honestly, on street tires, it can't take too much more than that anyway. Im' already starting to get loose from a roll in 3rd. But, even if I did crank it way up, the ramp up of boost is very easily controllable with the throttle It doesn't snap up at the crack of throttle like a stock T-II does. If I cranked that sucker to 25 psi, I can easily control it at 10 psi at low rpm if I'm passing someone on the highway.

I'm curious about the backpressure numbers before and after the swap. But regardless of that, those numbers don't mean anything if you are enjoying the car more with the smaller housing vs the bigger one.

Without a doubt, it's higher. I can feel it at 6k+. I thought about tapping for backpressure, but the fact is that I'm not looking to squeeze every last bit of power from this set up. I would be thrilled if I had a responsive engine combo, with a broad powerband that can make 325 whp without needing 30 psi to do it. I'm confident so far that this is going to hit all of those marks.

Damn, nice numbers, and the area under the curve,

Area under the curve = win. Almost every time. :-)

[contraption22]

Without a doubt, it's higher. I can feel it at 6k+. I thought about tapping for backpressure, but the fact is that I'm not looking to squeeze every last bit of power from this set up. I would be thrilled if I had a responsive engine combo, with a broad powerband that can make 325 whp without needing 30 psi to do it. I'm confident so far that this is going to hit all of those marks.

I went 11.70's with my old S70 and a .48 housing. I don't see why you couldn't do better than that.

[roachjuice]

i may have found my next hybrid to try on the omni

[Pat]

I went 11.70's with my old S70 and a .48 housing. I don't see why you couldn't do better than that.

No doubt...with more boost, I'm sure the turbo will support well more than 325 hp. 325 has just been my target number for this top end. If I can do that at a relatively low boost level, I'd be pretty happy.

[Shadow]

That's wicked spool RPM, I am over 4000 rpm on both the 8 valve and TIII heads. Damn it, should have tried it on my old 8 valve setup, lol.

Simon, you do realise that this IS a trade off, right? No one that is making 400+WHP Now is going to want to go backwards to a restrictive turbine housing like this.

It's just nice to know that they Can work for certain lower HP applications seeing there are plenty of them out there, prob collecting dust.

What's interesting is, with the proper comp cover the .48 A/R stage three sounds to be responing like a .63 A/R stage 1. IF that were true and it doesn't surge (which would be unlikely) it would be a Great turbine combo as the stage 1 .63 A/R is only good to around 350WHP and just under 400WHP if you clip the wheel.

[Force Fed Mopar]

I've been wanting to try a StgIII .48, but haven't been able to locate one yet. Jckreiger was supposed to have one, but he kinda fell of the map or something What would have to be done to make a stock .48 into a StgIII? Can they be machined out? I have a decent compressor for it.