So towards then end of the month i will be purchasing the turbo for my build. The plan......

1)stock motor until it craps the bed
2)once forged would like 500-700 wheel hp
3)not against buying two different turbos but would like to avoid it

A4 with 3500 stall 3.90 gearing so it will stay in boost once there.

i was worried about a chunk of the doomed ringland(s) getting into the turbo when the motor finally lets go(we all know it will eventually)

so i have been looking at the mpt70 with the .96 ar
http://www.vsracing.net/catalog/prod...roducts_id=812

and the gt4088 special by garrett
http://himni-racing.com/index.php?ma...roducts_id=741

1)should i go with the bigger garrett since it will stay in boost once its there?
2)when should i start seeing boost with either turbos
3)Is it a possibility that crap from the motor letting go will damage the turbo?
4) any other turbo recommendations?


if so i would like to stay journal bearing, would like to keep it cheap if possible this is my first turbo buildup and im trying to avoid destroying a high dollar turbo.

thanks guys.

 

That garrett is a 64.7mm turbo while the MPT70 should be close to a true 70mm turbo.

The MPT70 is cheaper and easily replaceable... if it were me and my final goals werent higher than a T70 can support, then perhaps the MPt70 is a decent choice.

 

For the price you cant beat it. Im building the same thing except im not waiting to blow the engine.

 

What about about a twin setup...would two MPT70s with a .68 ar work?

 

I thought about something like that but for the goals he has and being his first build 1 set of problems is easier to deal with than 2.....

 

I'm facing the same turbo choice decision at the moment, albeit a little different. I was wondering though if you guys can school me on the AR ratio thing in a cliff notes kind of way. I've read some of the tech articles, but none seem to be getting though to me in a meaningful way. I'm VERY well versed in engines, but not in turbo speak.

Background: fully forged 383, TF heads, building headers from 1 7/8 304 stainless. Auto trans to start with a change to M6 as time permits..

Not trying to hijack your thread. My appologies.

 

t74gts???

 

i am running twins on my b-body and they are t3/t4's with .50 fronts and .63 rears for a good spool not to quick...

stock bottom end.

 

I'd say start out with a T78GTS with the .84 housing. Move up to the .96 later for $200. It's about $1500.

Another option would be the TC76. It's a little smaller so it'll spool better, plus about $500 less.

Mike

 

yes..thats true..

but my question is would two T70s with a .68 work in a twin turbo app....say on a mildly built 355 or 383

 

Im considering doing single with your hot parts in the near future.
Would a MPT70 with a .96 AR fit on your log manifold setup?

 

Yes, but I am pretty sure the 3" Vband on the turbine housing for the DP isnt the standard size that Precision/T-netics/innovative use. If you wanted to use the MPT70, then swap in a Precision T76 down the road, you'll need to cut the old vband off the DP and weld a new on.

As far as fit though, shouldnt be a problem.

 

The V-band is standard you just have to cut the tabs on the turbo side to make it fit, its really really simple and took me less than a minute to work on mine. Im using a standard v-band flange on my down pipe and the modified clamp and it works perfectly.

 

Im sorry I dont want sound stupid, Im new to this turbo stuff, still learning as much as I can. So what your saying is you have to modify the clamp itself to fit the turbine housing exit, and not the turbine housing or DP?

This is the one Im looking at in a .96 AR

http://www.vsracing.net/catalog/prod...roducts_id=812

It shows a 3" V band clamp on that site as well.