JMFabrication O2 dump results
Thread Starter
Joined: Jan 2004
Posts: 11,406
Likes: 78
From: Northwest
JMFabrication O2 dump results
So using an O2 dump is no secret. Whatever brand you choose will always make a difference whether on a stock turbo or all the way up to a Black. Turbojunkie's car picked up 33whp and 80 FT LBS!!! with no other changes than a MAP downpipe on his 2005 VIII turbo.
We have long held that the reason is a reduction in backpressure allowing the turbo to work efficiently, the motor breathe better (less reversion), etc. I had been waiting for a chance to do a good test on one of our LR2.4 motors and a Black and finally got the chance. While the motors are all the same, getting the headwork and intake manifold to match up has been a challenge as no 2 owners have the same dream or budget when building. That is until now.
Test subjects-
Evo VIII
EnglishRacing 9:1 LR2.4
156mm rods
Bushmaster Street/strip Cylinder Head
Magnus V5
FIC 1450cc injectors (even kept this the same)
GSC S3s
GSC beehive with Ti retainer upgrade
Cams degreed in both
Omnipower 4 bar and SD tune
One has a TiTek O2 housing, the other has a JMFab O2 dump.
The results-
Is 70whp typical? Probably not to be honest. There are still some big reasons why it could be THAT much higher but every little bit makes a difference. Since the heads are hand ported there is a possibility that there is some variance there. The intercoolers are the same but sometimes one core will flow more than the other. Exhaust is the same so I will rule that one out.
While I dont think everyone will see a 70whp gain, I would be hardpressed to believe we wont see 40-50whp with one little mod. On Mikey's car we didnt see as much power over JohnnyTSi's (more like 50) but we did see faster spool and nearly 80 ft lbs. there as well.
Aaron
We have long held that the reason is a reduction in backpressure allowing the turbo to work efficiently, the motor breathe better (less reversion), etc. I had been waiting for a chance to do a good test on one of our LR2.4 motors and a Black and finally got the chance. While the motors are all the same, getting the headwork and intake manifold to match up has been a challenge as no 2 owners have the same dream or budget when building. That is until now.
Test subjects-
Evo VIII
EnglishRacing 9:1 LR2.4
156mm rods
Bushmaster Street/strip Cylinder Head
Magnus V5
FIC 1450cc injectors (even kept this the same)
GSC S3s
GSC beehive with Ti retainer upgrade
Cams degreed in both
Omnipower 4 bar and SD tune
One has a TiTek O2 housing, the other has a JMFab O2 dump.
The results-
Is 70whp typical? Probably not to be honest. There are still some big reasons why it could be THAT much higher but every little bit makes a difference. Since the heads are hand ported there is a possibility that there is some variance there. The intercoolers are the same but sometimes one core will flow more than the other. Exhaust is the same so I will rule that one out.
While I dont think everyone will see a 70whp gain, I would be hardpressed to believe we wont see 40-50whp with one little mod. On Mikey's car we didnt see as much power over JohnnyTSi's (more like 50) but we did see faster spool and nearly 80 ft lbs. there as well.
Aaron
Jesus, I am going to check with MAP now and see if I can switch to an o2 dump quick...I knew it was better but I will be in the 500-600whp land so I don't want to leave that much on the table.
Awesome comparo though, with variance I agree 40-50whp seems more reasonable but that is still a stupid amount of power!
Awesome comparo though, with variance I agree 40-50whp seems more reasonable but that is still a stupid amount of power!
Trending Topics
I have the MAP downpipe/dump and there are no fitment issues with my koyo. The only fitment problem I've had with the thicker koyo is the rad fan touching the FP compressor housing (hta green)...just had to trim a few a blades.
What kind of exhaust is on the car? Is it safe to say that at higher levels of boost the gains may not be so drastic? If both 02 housings have the same outlet ID I would think it would be safe to say the 02 dump is compensating for a restrictive exhaust system after the 02, which by all means is fine.. Thats a hell of a gain in power, thanks for sharing..
