Looking at getting a single larger turbo (no thanks on twins, not yet at least ).

Anyone have experience with the GTA4294? commonly used on detroit deisels, it looks very similar to a garrett GT42.

Leaning towards the Gt37 to ensure i still get "decent" spoolup..

Someone want to push me over the edge?

...
...

or would a GT35 be suffecient (400-500hp goal for now)

 

If you drive on the street at all, the 4294 is NOT for you. It doesn't think about spooling until ~2000rpm and finally lights at 23-2400. With a good amount of timing, I cannot spool the charger with any boost using a 89% convertor from DTT. Also, it takes a custom downpipe and adapter plate to work.

I would get a SPS66 or even a full B1.

JMHO,
brandon.

 

The spooling issue is really only a factor for the first starting gear though, as the turbo will not come down to idle speed between shifts.. so 3rd 4th and 5th gear will take significantly less time to boost..

Truck will have edge comp and jammer stg 5 injectors to compliment, that wouldnt run ok?

Turbos really not that big in size.. people use them on large 4cyl motors and small v6's with good success.

 

Ive looked at the SPS66 and B1's.. but cannot justify $1400 for a turbo, when 4294's go for under $500, and Gt37's about the same.

 

I want to keep taps on this. I was just looking at a SPS66. (trying to find i used one)

 

Any other thoughts? Im considering buying one and trying it out. 2nd gear may feel a little slow but im sure itll rip right through 3-5 no problem..Have to consider the t3 to t4 adapter though and how much it will push it away.. OR weld a new flange on the manifold.

OR:

Anyone have recommendations for a stock turbo off something else thats slightly smaller?

whether it be cat, detroit, cummins, etc..

 

i would go with a 37 should support 400 to 500

that 42 with a journal bearing and big turbine just wont cut it on the street

I had something on the same line cept my turbine wheel was smaller and it wasnt fun and only made 37lbs then yr out of rpm

that 37 has a 72+mm turbine wheel so u can put a 66mm inducer wheel on it and wouldnt have to worry about surge

 

or maybe a T-70 turbonetics with a real tight AR it would be slow but doable.

 

What worries me is the GT37 and S70 were turbos i was considering for my 2.5L 4cylinder dodge turbo..

Seems pretty small for a 5.9L. I know these trucks move alot more exhaust..

.63, .70 AR just seems way too small...

Im probably alone on this fence.

 

i had a Turbonetics T70 with a undived 81 a/r p trim wheel it didnt light till over 2000 RPM but with a tighter a/r its going to surge BAD the only way to get away from surge is to have the turbine wheel bigger than yr inducer turbonetics turbo are made for cars and the surge line and rpm the gas guys turn doesnt affect them as much as diesels were our max rpm is 2800 to 3500 on most 24v , its like breathen in yr mouth and blowing through a stop up nose ...I got a garrett now im going to try it has the 68+ wheel inducer and a 77+ turbine wheel ...


BTW smoken u got that other turbo yet ????

 

I was wondering about the gt4294 as well. I would love to run it since I already have one sitting on the shelf. Are you saying you think it won't spool in 1st until 2000 but will spool in gears after that? I was going to use it on my 454 but sold it and I just figured it was way to big for this motor. I need to do something though because I am running a 3K and a #100 plate and it is getting so hot I can barely get my foot into it.

 

it wont start spooling till 3rd or 4th ,,, 1st u have no load at all 2nd u might have some , just like dynoing yr truck u make power in the hi gears the truck needs a load to build boost , and fuel i had 150 hp with a FMS and that wasnt enough

Now if they made a smaller housing for the GT42 then u might get by with a say a 81 a/r sence the turbine wheel is just a bit larger than the inducer kinda like the k31 stuff

but iv looked for one cause i was going too try one and didnt have much luck
. I did find one place that would make a custom housing put it cost more than the turbo

hmm more i think about it , i think a body could go down to a 81 a/r at least try and check yr back pressure ,

person could get a regular housing and get a turbo shop to cut it out the fit the wheel then they need to weld the vband to the turbine housing , iv seen this done to holsets ,,,

Can one of u guys measure the Vband for the turbine side were it mounts to the CHRA ??? im guessing 3 1/2 ????

 

First gear or two itll probably slowly spool.. after that, as long as youre not a grandma shifter, it should be darn quick.

a turbo is a turbo, and on my car the first time it was about 3-4 seconds for spoolup to 18psi, but then every shift after it was less than 1 second to hit 18psi again..

the turbos not startin from scratch in every gear.. and the larger the turbo, more rotating mass, the less its going to slow down.

these diesels even have an advantage over traditional engines without a butterfly/throttle plate to backup on the compressor to slow it down..

if you get a boost controller itll be even faster.. i just noticed not many on these boards run a boost controller.. no wonder slow spoolup is an issue.

on my car it cut the spoolup time in half taking away vacuum/psi controlled boost (wastegate to turbo nipple). toss in a controller or a manual bleed of some sort.. itll spool.

no 2nd thoughts here now, it'll be GTA4294 in a month.

just gotta find a 5" vband downpipe thatll fit...

 

i had the same turbo on my car , and it was alot different

a boost controller isnt going to help spool if u cant make it spool to make the controller work

gas cars with 15 to 20lb is awsome and yeah u need a wastegate

15 to 20 is stock on a diesel u need 40+ to feel something

wastegates/controllers just control yr max psi u need,, its not getting there any faster from a controller

if i made 40 lbs @ 2500 rpm then i might look into a controller , depends on the turbo

 

Just for fun ill do something tonight to verify the spool time and post the results.

Im not going to say first what cause if i blow something i dont want anyone to know how stupid i was.

Will report back at aproximately 6pm AZ time.