BW 8374 Boost Creep Check
It is the same "C" housing which is optimized for 58, 64,70, 74mm exhaust wheels according to BW.
You can read up on the specifics here (pg24). There is a section on WG flow as well.
http://www.full-race.com/articles/efrturbotechbrief.pdf
You can read up on the specifics here (pg24). There is a section on WG flow as well.
http://www.full-race.com/articles/efrturbotechbrief.pdf
My 9180 seems to creep as bad or worse than the 8374. I'm hitting 17psi by 7000 with 0% DC on the controller. Im trying to turn the engine to 8500...
I have a 4" downpipe but a 3" resonator and old school 3" Racing Beat dual exhaust. Yesterday I swapped in a Turbosmart dual port actuator with the 7# spring and maybe 1/2 a turn of preload with a 4port solenoid. I was hoping the softer spring and less preload would get more stroke out of the internal gate. It didn't help at all. It DID help midrange a lot. I had the original open loop settings on my ECU and the thing made 17psi at 3800 in SECOND gear, so I'm happy about that at least. Dynoing next weekend hopefully.
I have a 4" downpipe but a 3" resonator and old school 3" Racing Beat dual exhaust. Yesterday I swapped in a Turbosmart dual port actuator with the 7# spring and maybe 1/2 a turn of preload with a 4port solenoid. I was hoping the softer spring and less preload would get more stroke out of the internal gate. It didn't help at all. It DID help midrange a lot. I had the original open loop settings on my ECU and the thing made 17psi at 3800 in SECOND gear, so I'm happy about that at least. Dynoing next weekend hopefully.
I am not surprised with the size of your exhaust.
My FC held 8 psi with the 9180 IWG with a 2.5" catback. I did not know the catback had that big of a bottle neck inside of it( only figured that out once I cut it open). As soon as I moved to a 4" DP/MP with straight through 3 inch catbck it shot up to 18psi or so so on the top end. For those reading there is no reason to run the 9180 less than 20psi, unless its a really healthy ported engine. It will not make any more power than the 8374( below 20PSI) on a stock, medium or large SP motor in my experience. It really starts waking up past 25psi.
Looking forward to your dyno.
My FC held 8 psi with the 9180 IWG with a 2.5" catback. I did not know the catback had that big of a bottle neck inside of it( only figured that out once I cut it open). As soon as I moved to a 4" DP/MP with straight through 3 inch catbck it shot up to 18psi or so so on the top end. For those reading there is no reason to run the 9180 less than 20psi, unless its a really healthy ported engine. It will not make any more power than the 8374( below 20PSI) on a stock, medium or large SP motor in my experience. It really starts waking up past 25psi.
Looking forward to your dyno.
Any thoughts on that approach (getting a 9180/9174 but only running it in the 350whp-450whp ranges)?
fendamonky
Quote:
I'm picking up a 9174 and I was actually planning on primarily running it below 20psi. I went with the 9174 over the 8374 primarily due to the theory that a larger turbo will make the same power with less effort, leading to a longer lifespan and greater chance of overall reliability. Response will suffer a little, but the EFRs seem to minimize that sacrifice.
Any thoughts on that approach (getting a 9180/9174 but only running it in the 350whp-450whp ranges)?
By less effort, you mean the larger compressor can be driven at a lower boost and make the same peak power as the smaller compressor at a higher boost?
I doubt this will be the case.
Yes, the engine can make the same peak power at a slightly lower boost.
But, the turbos share hot-side dimensions, so it is more effort (higher exhaust manifold pressure) for the motor to spin the larger compressor.
You would want an 8380 or an 8374 in the 1.45AR or an 8380 in the 1.45AR exhaust housing to achieve less effort on the motors part at the same peak power.
Your engine is working harder during lag from a larger compressor.
Your engine is working less hard during lag from a larger exhaust side.
Quote:
I'm picking up a 9174 and I was actually planning on primarily running it below 20psi. I went with the 9174 over the 8374 primarily due to the theory that a larger turbo will make the same power with less effort, leading to a longer lifespan and greater chance of overall reliability. Response will suffer a little, but the EFRs seem to minimize that sacrifice.
Any thoughts on that approach (getting a 9180/9174 but only running it in the 350whp-450whp ranges)?
By less effort, you mean the larger compressor can be driven at a lower boost and make the same peak power as the smaller compressor at a higher boost?
I doubt this will be the case.
Yes, the engine can make the same peak power at a slightly lower boost.
But, the turbos share hot-side dimensions, so it is more effort (higher exhaust manifold pressure) for the motor to spin the larger compressor.
You would want an 8380 or an 8374 in the 1.45AR or an 8380 in the 1.45AR exhaust housing to achieve less effort on the motors part at the same peak power.
Your engine is working harder during lag from a larger compressor.
Your engine is working less hard during lag from a larger exhaust side.
fendamonky
Well, shoot...
On the other hand, with the larger compressor providing the same peak power at a lower boost you would be enjoying the benefit of lower intake air temperatures.
I wouldn't say that is letting your engine work less hard, but it can be less hard on the engine all other factors the same (which as pointed out above they would not be).
Its a lot of factors to try to balance!
Thread Starter
Joined: Feb 2002
Posts: 9,282
Likes: 703
From: Arlington, VA
As a reference, I just had mine out to Summit Point on Sunday, in stank-*** hot conditions, running 13psi, with a new GReddy V-mount set up and turbine shield, and IATs stayed in the mid 40's, once getting as high as 52 in traffic. Just a month ago I was out without a turbine shield, and the best SMIC on the planet (CWR replica with Bell core), and IATs were hitting high 60's to 70.
I'd save yourself the hand wringing, and just get an 8374 and a good V-Mount set-up.
I'd save yourself the hand wringing, and just get an 8374 and a good V-Mount set-up.
As a reference, I just had mine out to Summit Point on Sunday, in stank-*** hot conditions, running 13psi, with a new GReddy V-mount set up and turbine shield, and IATs stayed in the mid 40's, once getting as high as 52 in traffic. Just a month ago I was out without a turbine shield, and the best SMIC on the planet (CWR replica with Bell core), and IATs were hitting high 60's to 70.
I'd save yourself the hand wringing, and just get an 8374 and a good V-Mount set-up.
I'd save yourself the hand wringing, and just get an 8374 and a good V-Mount set-up.
I've been running a VMIC for years now, got it from RE:worx, a shop in the UK that I'm sure Marf knows of
it would keep temps at approx 10 deg over smbient regardless of boost or cruising. V-mounts are wonderful mods!!
On the other hand, with the larger compressor providing the same peak power at a lower boost you would be enjoying the benefit of lower intake air temperatures.
I wouldn't say that is letting your engine work less hard, but it can be less hard on the engine all other factors the same (which as pointed out above they would not be).
Its a lot of factors to try to balance!
I wouldn't say that is letting your engine work less hard, but it can be less hard on the engine all other factors the same (which as pointed out above they would not be).
Its a lot of factors to try to balance!(Sorry for the minor derail Peter.. Def gunna want/need to link up with you at Summit Point next year)
Thread Starter
Joined: Feb 2002
Posts: 9,282
Likes: 703
From: Arlington, VA
RE WORX needs better pics of the stuff on their site. But I digress.
Here's the video from last month at Summit, a shitty 1:25 on R888's. I HATE those tires. I strapped on two year old bald Hoosiers this time and ran 1:21.
Next month at Watkins Glen it should FLY. I've heard the new re-pave has so much grip, people are breaking stuff.
Here's the video from last month at Summit, a shitty 1:25 on R888's. I HATE those tires. I strapped on two year old bald Hoosiers this time and ran 1:21.
Next month at Watkins Glen it should FLY. I've heard the new re-pave has so much grip, people are breaking stuff.
We just had another customer hold 15 psi with his cast IWG 9180 kit with the 3.5" downpipe option. Its also on a street ported engine with no Cat( rest of the exhaust is free flowing 3"). Car made 410rwhp on a mustang dyno( 470rwhp on a dynojet!)
I am really trying to figure out how is it possible to hold low boost with straight throught exahust system? I just swap out a SMB resonated midpipe with 3 inch sub cat, for the magnaflow resonated midpipe, I went for a test drive and in 3rd wot I hit 1:16 bar close to 16:50 psi, boost gauge show indentical reading witht he boost controoler off. Before i had the smb with the RB dual tip with the Boost controller off i hit 9 psi. I have the 8374 IWG kit.
8374 Turblown cast manifold - 3" Exhaust, Aggressive Street Port, couldn't get it lower than 17.5psi up top. It would hold 15 (medium canister) all the way to 6000 and then start to creep. I can probably get it a bit lower with a smaller canister.
I'm going to toss in a high flow cat to quiet it down a bit anyway, so that restriction should add some BP and help me limit the boost. Also throwing in water injection for those times I need to run 91.
I'm going to toss in a high flow cat to quiet it down a bit anyway, so that restriction should add some BP and help me limit the boost. Also throwing in water injection for those times I need to run 91.
I have the IRP manifold and have no creep issues. Large streetport and EFR 8374 with a resonated mid pipe and RB dual tip. Graphs showing boost are in my thread.
Last edited by Molotovman; Oct 31, 2017 at 08:59 PM.
That RB Dual dip is probably creating enough back pressure to keep the creep down. My exhaust is 3", no resonators and no cats. I'm going to throw in a restrictor or a high-flow cat to see if it reduces creep.
Healthy stock port FD Rx7 with our cast EFR IWG 8374 kit, pump gas, full 3" exhaust( no cat), medium BW actuator. 4th gear pull, holds 11~psi. See attached datalog. Please note this car does not go WOT until the midrange. I have since tuned it with the controller on, and it sees about 16 psi by 2900rpms( not fully ramped up all the way, but close).