Rear Mount Turbo "MAF" Placement

[do92sc400]

Hey guys, I'm getting ready to start my remote turbo set up for my sc400. I decided to go with a single turbo versus a twin set up, simpler to install in the wheel well (after slight modification) and to run a single oil feed line with a surflo pump to return it versus having to lines. Where the exhaust splits into two pipes at the rear is where instead I will run a single pipe to the turbo tucked up and shielded in the wheel well. Turbo size prob t70 or t3/t4 debating which one based on when I want boost to kick in. I'm looking for just 5-7.5 psi to run the stock comp with fmu and 250 fuel pump.
My question is the MAF sensor placement. Can I have boost going into the MAF from the turbo, or must I have the MAF measure air going to the turbo? Any comments?

 

[stevechumo]

Hey guys, I'm getting ready to start my remote turbo set up for my sc400. I decided to go with a single turbo versus a twin set up, simpler to install in the wheel well (after slight modification) and to run a single oil feed line with a surflo pump to return it versus having to lines. Where the exhaust splits into two pipes at the rear is where instead I will run a single pipe to the turbo tucked up and shielded in the wheel well. Turbo size prob t70 or t3/t4 debating which one based on when I want boost to kick in. I'm looking for just 5-7.5 psi to run the stock comp with fmu and 250 fuel pump.
My question is the MAF sensor placement. Can I have boost going into the MAF from the turbo, or must I have the MAF measure air going to the turbo? Any comments?

You can leave the MAF sensor in stock location, which mean the turbo is before it. That's my setup. As long as the MAF sensor is at least 12 inches after the BOV, you should be ok. The only problem that you'll have when the BOV too closed to the MAF is the engine will stall if you let off the gas when boosting hard.

 

[Lextreme II]

Awesome... let me know when u starting. I live pretty close and perhaps i can give you some pointers. Do you find that area be big enough to house a T70?

 

[do92sc400]

So Stevechumo, what your saying is that I can run boost from the turbo, to the MAF sensor, to the engine?
That is what I'm hoping for that way I was going to run the air filter from the trunk to the turbo (that's in the wheel well).

-Lextreme I'm hoping to have everything ready in about a month or so, I'm in the military so time is really stretched. What I will do is get all the material first and post it to see what you think if that is fine.

 

[XR8tt]

Yep blow through has less issues.. It reads lighter density, if in take temps rise.. Pays to have straight pipe before maf as incoming air tends to be on outside of bends etc.. Most the Mustang guys do it this way with recalibrated maf for larger injectors...
Yes bov between maf and turbo, usually just after intercooler.. Though there is some say before intercooler so your venting hot air...

 

[stevechumo]

So Stevechumo, what your saying is that I can run boost from the turbo, to the MAF sensor, to the engine?
That is what I'm hoping for that way I was going to run the air filter from the trunk to the turbo (that's in the wheel well).

-Lextreme I'm hoping to have everything ready in about a month or so, I'm in the military so time is really stretched. What I will do is get all the material first and post it to see what you think if that is fine.

Yes. You can. I'm having that setup and boost at 9 psi with no problem.

I'm concerning about the huge T70 if you can make it fit under the car or wheel well.

 

[do92sc400]

For the boost level Im looking for, as well as, fitment what turbo size would you recommend. Im seeing that the t3/t4 68 a/r might be to small. I was thinking that the smaller size would help build boost faster given that it will have to travel a further distance from the rear to the engine.
I'm not really looking at this time to make huge power just enough to make it more comparable to what is out today. power to be at about 2500-5500rpm is ok for me.

 

[XR8tt]

Twin T3's up to .62 A.R [almost any single 2l turbo x's 2]
T3's came from 3l engines but still work on 4l engine..
Gt35R as single which has intergrated wastegate with 1.06 A.R..
Anything with a combo making 600 to 700 h.p..
The T04Z is my favourite with engines this size. External gated..
Then there's the Borge warner / KKK turbo's..S374 etc...

Two Masterpower Gt25's with .42 A.R would spool quick...

 

[Lextreme II]

I had twin Garrett T3 with .48 A/R and it was fun. My LS400 tires spin from a stop and keep on spinning until about 30-40 feet. I would recommend T3 with .48. Later I put in .68 and the lower end was there and it wasnt as fun as the .48.