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Old 07-31-2008, 01:39 AM   #1
Patrick Olsen
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Default Latest dyno results: 145hp, 144ft-lb on Mustang dyno

Earlier this year I moved from RI to WA, and at the end of May I finally got the Subaru shipped out to meet me. The last time I dyno'd the car was back in August '07, and I have plans to put a new/rebuilt engine in, so I wanted to re-do my "baseline" since I'm in a new area and will be using a new dyno.

While the car was on the East Coast in my brother's hands 2nd gear died, so the first order of business when it got here was to fix the transmission. I already had an STI 6MT on a pallet in my garage, so rather than fixing the 5MT I figured I would just go ahead and have the 6MT installed. That work was handled by Steve's Pacific Import Auto (PIA) in Tacoma, WA.

The other change was the installation of a re-clocked ECU, which has raised the rev limiter to ~7150rpm. We didn't actually run it that high on the dyno, but it was supposed to be raised 10%, and the engine ran to 7000rpm without hitting the rev limiter, so it's up there somewhere. The guy who did the reclocking says it should not affect the fuel tables or spark tables, but I didn't remember to bring my other, stock ECU to do a comparison on the dyno. (One side effect of the re-clocking is that my PocketLogger won't sync to the OBD2 port anymore, nor would PIA's Subaru Select Tool, so I can't log timing to see what it's doing.)

The engine that's in the car is an ebay special that I installed last year. It's a JDM engine, and Steve pointed out to me that it's actually a hydraulic lash adjuster (HLA) motor (like the '96 2.5GT engine, which was different than the '97-99 2.5GT engines). Interestingly, the '96 2.5GT was rated at only 155hp vs. 165hp for the '97-99 cars, but my dyno results both at PIA and back at Dentsport Garage on their Dyno Dynamics seem to indicate this engine is plenty healthy. The engine is all "stock" from oil pan to throttle body (I say "stock" since it's an imported engine and I don't know if there are differences from a USDM EJ25D). I have an Injen CAI, OBX header, S-AFC, hi-flow cat, Stromung cat-back, stock pulleys, the STI 6MT, and Fidanza aluminum flywheel. Note that I had no illusions that the engine would make power up high, I just wanted a curve to 7000rpm so I could compare when the new engine goes in.

So, here's the graph:


145hp @ 6200rpm
144ft-lb @ 5000rpm

On the Dyno Dynamics those numbers were:
125hp @ 6000rpm
130ft-lb @ 4000rpm

On either dyno, you can definitely see that the engine just runs out of air at the top end. At 5200rpm the torque curve just starts dropping like a rock. By comparison, look at the green torque curve from this dyno of my old engine with Cobb-ported heads and reground cams - torque holds its ground at high RPMs much better. Running some numbers, for the stock heads/cams engine in the car now, on both the Dyno Dynamics and the Mustang dyno, the torque @ 6500rpm is 78% of torque at 5000rpm. For the Cobb heads/cam engine, torque @ 6500rpm is 90.5% of torque at 5000rpm! That's quite a difference!

Next up is to test the two ECUs I've got (stock vs. re-clocked), and then to do an intake manifold comparison (stock vs. GrimmSpeed PnP - just shipped them a manifold today). Theeeennn, hopefully I'll have the new engine built - same old Cobb heads and cams rebuilt with TWE springs and retainers, higher rev limit, ported intake manifold, lighter rotating assembly, and ~10.8:1 CR. I'm definitely curious to see how much power it can put down.

Pat Olsen
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Old 07-31-2008, 02:00 AM   #2
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Impressive! I'm looking forward to seeing those numbers too. Glad the 6mt is treating you well. What gear did you make that pull in, out of curiosity?

Aaron
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Old 07-31-2008, 02:50 AM   #3
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That is interesting,wonder if I could have my ecu reflashed for rev limit removal...maybe the governor could disappear also...

Anyway, are you gong to be using new pistons for the higher CR? I figured you would need to use basically the same HG thickness as stock.


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Old 07-31-2008, 11:39 AM   #4
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Quote:
Originally Posted by fastenova View Post
What gear did you make that pull in, out of curiosity?
4th gear.

Quote:
Originally Posted by ballitch View Post
Anyway, are you gong to be using new pistons for the higher CR? I figured you would need to use basically the same HG thickness as stock.
It's a Phase II shortblock with OEM 100mm pistons + DOHC heads and STI (I think) HGs.

Pat
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Old 08-02-2008, 05:17 AM   #5
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Cool stuff Pat. I just picked up a gt and will be doing similar things with it. As an added bonus I have a dyno at work so I'll be doing some pulls too.

I doubt I'll get too far into things though since I'd rather just swap in a 2.5 turbo motor down the line.
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Old 08-02-2008, 04:02 PM   #6
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glad to see this pat

when my old 2.5i was tuned, i had a 7k redline also, but i could feel the powerband fall off at about 6k or so just like your chart shows
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Old 08-02-2008, 10:04 PM   #7
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Quote:
Originally Posted by jamal View Post
Cool stuff Pat. I just picked up a gt and will be doing similar things with it. As an added bonus I have a dyno at work so I'll be doing some pulls too.
Cool. The engineer in me always likes to see more data. What type of dyno do you guys have?

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I doubt I'll get too far into things though since I'd rather just swap in a 2.5 turbo motor down the line.
Boooooorrrriiiiiiiinnnngggg. If I wasn't so stubborn I would've done the same thing long ago, but now I just keep fiddling with the N/A route.
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Old 08-03-2008, 04:30 AM   #8
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Quote:
Originally Posted by Patrick Olsen View Post
Cool. The engineer in me always likes to see more data. What type of dyno do you guys have?


Boooooorrrriiiiiiiinnnngggg. If I wasn't so stubborn I would've done the same thing long ago, but now I just keep fiddling with the N/A route.
Land and sea. I intend to put on the same headers, and probably replace the intake and see what we can do to tune it.

As for the swap, well, we tuned a 20g "ish" turbo today, and with enough race gas made 370whp.
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Old 08-04-2008, 08:06 PM   #9
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Let us know how it goes, were excited to see results on the 2.5 na manifolds!!

www.grimmspeed.com

Mike
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Old 08-05-2008, 12:09 PM   #10
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Nice work man. Tell me more about this ecu please?!?
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Old 08-05-2008, 02:04 PM   #11
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Qman, you got a PM......

Pat, nice results! I wonder if you can get some sort of timing log from the dyno itself?


Jay
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Old 08-22-2008, 09:37 PM   #12
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Forgive my ignorance, I don't know much about tuning Subaru engines... but is 12.8 max A/F still kind of low for an N/A motor? Can that be safely raised closer to the theoretical maximum power point (~13.8:1)? Also, it looks like the AFR is all over the place down low... any idea what causes that?

It does appear that it just can't flow worth crap above 5k where torque begins its steady decline... what is generally the limiting factor on these motors? Cams? Heads? Intake manifold?
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Old 08-23-2008, 04:05 AM   #13
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Quote:
Originally Posted by ProDarwin View Post
Forgive my ignorance, I don't know much about tuning Subaru engines... but is 12.8 max A/F still kind of low for an N/A motor? Can that be safely raised closer to the theoretical maximum power point (~13.8:1)? Also, it looks like the AFR is all over the place down low... any idea what causes that?
From what I've seen, peak power is in the 12.5-13:1 range. Anything leaner than 13:1 and it starts to lose a bit of power at the top end. Although this is the only car I've ever done any dyno tuning on, I was expecting to see more power as I leaned it out a bit more, but turns out that wasn't the case.

As for the bouncy AFR down low, my understanding (based solely on what people say here, not any real technical evidence) is that the older pre-01 or pre-02ish ECUs go to open loop at once you're WOT and >4krpm. So at lower RPM I think it's still closed loop, and the funky AFR is due to the ECU and S-AFC fighting.

Quote:
Originally Posted by ProDarwin View Post
It does appear that it just can't flow worth crap above 5k where torque begins its steady decline... what is generally the limiting factor on these motors? Cams? Heads? Intake manifold?
The heads actually flow really, really well for stock heads. The two exhaust ports in each head are different lengths, so that's not optimal, but the heads still flow really well. I think the main limitation is the cams, and the intake manifold is probably also an issue. The fact that the flat engine design restricts you to a long runner intake (unless you do something really funky) certainly doesn't help top end power.

Pat

Last edited by Patrick Olsen; 08-23-2008 at 04:11 AM.
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Old 08-23-2008, 11:06 AM   #14
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so with the rev limiter hack you cant connect an obdII tool to scan for codes or you just can view live data?
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Old 08-23-2008, 05:36 PM   #15
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The two devices that have been tried - my old PocketLogger using a Palm Vx, and the Subaru Select Tool - could not sync with the OBD2 port to reset the CEL.

Pat
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Old 08-23-2008, 10:17 PM   #16
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Numbers from the flow bench indicate the biggest limiter to be the intake. The cams can be ground to allow for top end power increases. The heads can be ported for increased flow and velocity for the N/A application. However, the intake decreases some of the gains of porting. I tried the bigger '05+ intake also. It flowed huge numbers but had less velocity which would show as loss of power for N/A's. I have not tested the ceramic coating yet. That wil happen as soon as I get my car back together.

Thanks for the info Jay. It will help attain better numbers for sure!!
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Old 08-23-2008, 10:18 PM   #17
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Unfortunately, it's true. The rev limit mod renders the OBDII port useless. I don't know why, but it is what it is.....

Glad to help out, Qman!!!!

Jay
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Old 08-23-2008, 11:17 PM   #18
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Quote:
Originally Posted by Qman View Post
I tried the bigger '05+ intake also. It flowed huge numbers but had less velocity which would show as loss of power for N/A's.
Is that based on actual dyno/road testing, or just speculation based on flow bench numbers? And I don't mean that in a dickhead-ish way, I'm just curious. My understanding is that when we talk about "intake velocity" with regards to engine performance, it's all about the intake ports on the heads. The intake manifold plays a small role, but even the "big" '05 manifold has essentially the same size runner ports where it joins the heads, so I wouldn't think it would adversely effect performance. I could be wrong, of course.

Oh, if you have flow bench numbers for different intakes, I'd be curious to see them.

Unfortunately, I don't have any easy way to try it out, since the bolt pattern doesn't match my heads. I actually have an '05+ intake, which I bought with the intention of having someone merge it with the runners/head flanges of one of my spare DOHC manifolds. I've never seriously looked into it, though, and it seems like it would be tough to do cleanly.

Pat
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Old 08-24-2008, 12:10 AM   #19
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^^^so you should send it to me..... I'll trade you 2 twin throat FoMoCo throttlebodies for it!

Jay
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Old 08-24-2008, 02:31 AM   #20
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What the hell am I gonna do with 2 twin-throat Ford throttle bodies? (Are these '03+ Cobra TBs or something? I will need a cable TB with built-in IAC for the EZ30R at some point...)

I haven't given up on the idea of using the '05 manifold, I just haven't put much thought into how it could be done and finding someone to do the work. When I was still in New England, Dentsport Garage had said they could do it, but that was about a month before I moved and in those last few weeks I just never had a chance to get up to their shop to drop off the two manifolds. I've actually thought about doing it myself, just using some silicone elbows to join the center plenum section of the '05 with the injector/flange section of the DOHC intake. I would still need to figure out the cable throttle body action, as there's no provision for a throttle cable bracket (not a huge obstacle) and the bolt pattern for the DBW TB is a bit different (a bigger obstacle).

Pat
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Old 08-24-2008, 09:52 AM   #21
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Originally Posted by Storm View Post
Unfortunately, it's true. The rev limit mod renders the OBDII port useless. I don't know why, but it is what it is.....
Yeah, that could be a problem for me, since they use OBD-II for testing purposes in NoVA. Oh well, maybe when my car makes "Antique" status.
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Old 08-24-2008, 01:08 PM   #22
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Fortunately for me, since I'm stationed out of state, I don't have to worry about CT emissions - I just send in a letter to get a waiver every year. Of course, even with the non-re-clocked ECU, I pop CELs every couple of days due to the lightweight flywheel, so I'd have a helluva time passing if I did have to get it tested.

Pat
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Old 08-24-2008, 01:40 PM   #23
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For me, I do an ECU reset just before testing to get rid of any CEL. When they plug in and can't link up, they test for tampering (wire cutting). When that comes through clean, they have to hook up the sniffer and run the motor at an rpm simulating 25mph. It always ends up passing.

Yeah, I make them work for it....but they make the rules, not me. I could tell them exactly what they need to do and save everyone alot of time....but they think they know best, so I let 'em go through the whole ordeal, smirking through the window.

Jay
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Old 08-24-2008, 02:05 PM   #24
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Quote:
Originally Posted by Patrick Olsen View Post
Is that based on actual dyno/road testing, or just speculation based on flow bench numbers? And I don't mean that in a dickhead-ish way, I'm just curious. My understanding is that when we talk about "intake velocity" with regards to engine performance, it's all about the intake ports on the heads. The intake manifold plays a small role, but even the "big" '05 manifold has essentially the same size runner ports where it joins the heads, so I wouldn't think it would adversely effect performance. I could be wrong, of course.

Oh, if you have flow bench numbers for different intakes, I'd be curious to see them.

Unfortunately, I don't have any easy way to try it out, since the bolt pattern doesn't match my heads. I actually have an '05+ intake, which I bought with the intention of having someone merge it with the runners/head flanges of one of my spare DOHC manifolds. I've never seriously looked into it, though, and it seems like it would be tough to do cleanly.

Pat
Based purely on flow bench numbers. The biggest problem is in the runners themselves. The bend angles cause slowdowns in air flow. This is coming from our porter. We also have more than one person doing test ports on the sohc heads right now. If there is a better way to port them we'll find it.

Hopefully, in the next month I will be back on the dyno to get number for the heads, intake and throttle body spacers, then the new cams I am coming up with. And of course, the re-clocked ecu. The nice thing is I will be using the exact same dyno as Pat just did and we will be able to compare numbers.

This is the sheet from my first runs on that dyno.



And comparing a stock RS.



Current set up includes SPT intake, torque cams, EL header, lightened flywheel and perfect power 6. Pretty mild set up that gives good numbers. Hoping to acheive 200 at the wheels with the next set up.
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Old 08-24-2008, 02:06 PM   #25
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Quote:
Originally Posted by Storm View Post
For me, I do an ECU reset just before testing to get rid of any CEL. When they plug in and can't link up, they test for tampering (wire cutting). When that comes through clean, they have to hook up the sniffer and run the motor at an rpm simulating 25mph. It always ends up passing.

Yeah, I make them work for it....but they make the rules, not me. I could tell them exactly what they need to do and save everyone alot of time....but they think they know best, so I let 'em go through the whole ordeal, smirking through the window.

Jay
What do they check for tampering?
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