MFS 6265 turbo results 9.96@135.73 ***updated 9/19/2014***

bison

Moderator
Staff member
Dec 19, 2005
16,823
1,535
113
43
CT
Atco is the best at a rental. I seen 7 second car making passes with just a roll bar no cage. Stupid on the driver but they seem to look the other way at rentals. Car is a grudge car.
I'm not worried about it. I need to make license passes with the other car and I'll be good to go


BPE2013@hotmail.com
 

MCH86GN

Well-Known Member
Aug 20, 2008
1,267
52
48
Back pressure data I aquired today. Air was about as shitty today as it was the day I dynoed. I noticed my GM style 3 bar MAP was reading 105kpa with key on engine off. Probably should be 98kpa with the crap air we had today. Anyway 28-29psi manifold pressure and approximately 40psi drive pressure. 1.37:1. This is using traditional wastegateing with an internal gate. This turbo is a lot better than I thought:



BPE2013@hotmail.com
Is the 1.37:1 your PR? If so, the the method I seen to calculate it had to be wrong. PR = (boost + 14.7)/14.7.
 

bison

Moderator
Staff member
Dec 19, 2005
16,823
1,535
113
43
CT
Backpressure÷Boost=PR. I think...
40÷29=1.37
That's for comparing exhaust to intake pressure. Not to be confused with the compressor pressure ratio. The correct way is using hot boost though. Which would improve the ratio. I don't have a hot boost calibrated MAP sensor so I used cold boost at the intake manifold after its seen pressure drop from the compressor outlet.


BPE2013@hotmail.com
 

Quik Six

Well-Known Member
Jun 22, 2001
1,058
80
48
71
Edmond, Oklahoma
Congratulations !! I've had a 6265 JB since they first came out and I watched with a lot of interest when you tested a lot different turbos on one car, same engine and shared the results. Your results verified that I had picked the right turbo for my needs.

You are a real asset to the TB community as you share your knowledge and experience with us.

Thanks.

Phil Engle
 
  • Like
Reactions: NyBlankets

MCH86GN

Well-Known Member
Aug 20, 2008
1,267
52
48
That's for comparing exhaust to intake pressure. Not to be confused with the compressor pressure ratio. The correct way is using hot boost though. Which would improve the ratio. I don't have a hot boost calibrated MAP sensor so I used cold boost at the intake manifold after its seen pressure drop from the compressor outlet.


BPE2013@hotmail.com
I see, I'm confusing the PR from the compressor map to the ratio of exhaust/intake pressure.
 

V6sleeper

Well-Known Member
Jan 18, 2011
1,486
205
63
long island,ny
X 1M!
I am continually amazed how much you (Bison) test, proof, know and share. Those in the community who read and listen are all better because of it!
I agree 100%, theirs nothing better then tests and comparisons with these cars, thank god somebody has the means and the knowledge to do so..(y)
 

BigReade

Buick City Boy
Jan 21, 2014
187
15
18
Tucson
just read this entire thread, and have to say, I am excited to get this turbo on the new engine and have some fun!
 

MCH86GN

Well-Known Member
Aug 20, 2008
1,267
52
48
just read this entire thread, and have to say, I am excited to get this turbo on the new engine and have some fun!
Good luck. I'm planning on getting this turbo as well. I'm supposed to rebuild this coming spring, if everything goes right. I'm looking to push my car into the low 10s range. It will be challenging and fun, I'm sure. I won't be able to try this year, even if I rebuild. I will need to have my transmission rebuild to handle the addition power and replace some other drive train components, heavy duty u joints, axles, etc. The transmission rebuild will have to wait another year.
 

BigReade

Buick City Boy
Jan 21, 2014
187
15
18
Tucson
Good luck. I'm planning on getting this turbo as well. I'm supposed to rebuild this coming spring, if everything goes right. I'm looking to push my car into the low 10s range. It will be challenging and fun, I'm sure. I won't be able to try this year, even if I rebuild. I will need to have my transmission rebuild to handle the addition power and replace some other drive train components, heavy duty u joints, axles, etc. The transmission rebuild will have to wait another year.
Thanks man!

I too am rebuilding, so I decided it was time to upgrade the turbo. My tranny only has a few hundred miles on the fresh build, however, it was built for my stock setup, lol, se we shall see. I need to upgrade all of the driveline parts as well. That's why I'm only looking to run it on low boost for now, 18-20# or so. I'll eventually want to turn the wick all the way up, but for now I'll try to reserve that for the occasional time I want to get booted from the track, lol.
 

MCH86GN

Well-Known Member
Aug 20, 2008
1,267
52
48
Thanks man!

I too am rebuilding, so I decided it was time to upgrade the turbo. My tranny only has a few hundred miles on the fresh build, however, it was built for my stock setup, lol, se we shall see. I need to upgrade all of the driveline parts as well. That's why I'm only looking to run it on low boost for now, 18-20# or so. I'll eventually want to turn the wick all the way up, but for now I'll try to reserve that for the occasional time I want to get booted from the track, lol.
Because of my transmission, I won't run no more than 15-17# of boost. It will be interesting to see what I can do with running close to stock boost. This will give me a chance to gain more experience with tuning and launching the car. Not sure once I have the completed rebuild if I will launch off a trans brake or not. I'll discuss this with my engine/transmission builder.
 

bison

Moderator
Staff member
Dec 19, 2005
16,823
1,535
113
43
CT
Just an update on the stock shortblock used here. It's still together and swallowing 32-33psi boost via a MFS 6766 on 93/alky. It's up approximately 50whp peak and over 70whp at 5600rpm over the MFS 6265. Haven't and don't plan on running this car again but it's a lot of fun on the street
 

Mr.Spool

Well-Known Member
Nov 6, 2006
4,313
569
113
Just an update on the stock shortblock used here. It's still together and swallowing 32-33psi boost via a MFS 6766 on 93/alky. It's up approximately 50whp peak and over 70whp at 5600rpm over the MFS 6265.
That's a solid gain!