Turbo recommendation for ~450 wtq? Stock location...

[tocinoman25]

My guess would be right at 4k or earlier even?

 

3600-3800 seems to be peak spot from plots ive seen on the 2.5l

[jcole05]

Quick update-shop needed to add a secondary fuel pump as they were seeing my car run lean during tuning of the Dom 2.5xt-r (10cm hotside). Early returns are promising at slightly > 400wtq and > 400 whp at 21psi. Going to try to get to 25 psi tomorrow.

 

More to come. B

[LatentWagen]

Let that 2.5xt-r eat! If they're above 400wtq at 21, 25psi sounds promising...

[Rhitter]

Quick update-shop needed to add a secondary fuel pump as they were seeing my car run lean during tuning of the Dom 2.5xt-r (10cm hotside). Early returns are promising at slightly > 400wtq and > 400 whp at 21psi. Going to try to get to 25 psi tomorrow.

 

More to come. B

 

Any idea what the curve looks like?

[jcole05]

No - I've asked them to scan and email to me but I may just need to drop by and get dyno plots as they go. Supposedly at least one more turbo will be done tomorrow.

 

Anyone know off the top of their head (I can do a search of course) about where this 2.5xt-r should make peak power?

[LatentWagen]

Anyone know off the top of their head (I can do a search of course) about where this 2.5xt-r should make peak power?

 

Depends on your heads, but I'd guess somewhere after 6500rpm. If you're doing it right, closer to 7500

[fahr_side]

On a GT3071R we'd normally see peak somewhere around 6k4 or 6k5rpm with the D25 heads and usual supporting mods. I'd expect the same on the 2.5XTR.

 

 

Sent from a device using some software.

[jcole05]

Thx. Will post dyno plots when I get em. Can the Dom2.5 hit maximum torque and boost by mid 4000s?

[joeleodee]

My buddy has tuned a 2.5xtr on E85. Here's the VD plot. Keep in mind that this is an extremely conservative tune at only 20psi and low timing. It was tuned to conserve the stock long block. Nevertheless, jump the timing and boost, the wtq would sharply increase with the power curve riding higher than what you see here. Keep in mind, dyno plots between this and the 1.5xtr are similar, but the ladder spools quicker while giving up a small amount of power up top.

 

[jcole05]

 

This is off track a bit as my car didn't get additional tuning done...booster fuel pump didn't come in until late in the PM.

 

But since I am hearing the Dom2.5xt-r so far is hitting maximum torque in my preliminary tune at 5000rpm, I wanted to post my Tomioka plot (airboy, not official dyno) prior to the work I am having done now (which includes changing to an FMIC and then getting 5-6 turbos tuned on my car for those new to the thread).

 

Anyway, why am I so slow to build boost, both (apparently) on the Dom2.5xt-r and on this Tomioka? Joe - your buddy's pic above lets me know that I should be hitting peak torque a LOT sooner on the Dom2.5xt-r...

 

In a sec, I'll post an airboy dynojet on my old BNR 16g setup too just for comparison to see if it is also slow to build boost. It certainly didn't seem so at the time, but the Tomioka was noticeably very laggy to me once I switched.

 

Thanks.

[jcole05]

 

Here is my 16g. It still looks a bit slow to build compared to the plot by Joe with the much larger Dom2.5xt-r.

 

Any thoughts? These dynojet runs on the 16g and Tomioka are about 4 years apart and the car has been inspected, tuned, had an engine rebuild, new headers, pipes, etc. all since then. Why the delay in spinning the turbine?

[fahr_side]

16G spool looks pretty average. I've seen earlier and later. 2.5XTR looks unreasonably slow to spool for you, like a massive exhaust leak.

 

 

Sent from a device using some software.

[rebourne]

My buddy has tuned a 2.5xtr on E85. Here's the VD plot. Keep in mind that this is an extremely conservative tune at only 20psi and low timing. It was tuned to conserve the stock long block. Nevertheless, jump the timing and boost, the wtq would sharply increase with the power curve riding higher than what you see here. Keep in mind, dyno plots between this and the 1.5xtr are similar, but the ladder spools quicker while giving up a small amount of power up top.

 

 

It's making ~285 at 4k! Anyone that says "but it doesn't spool like my OEM VFXX" needs to be slapped.

[jcole05]

16G spool looks pretty average. I've seen earlier and later. 2.5XTR looks unreasonably slow to spool for you, like a massive exhaust leak.

 

Exactly what am thinking. Funny thing...back to the UEL and ELH issue. That all came about when an exhaust leak was noted in my Perrin ELH (which was of course on the car with the 16g). But, while that certainly could have been true - I'd had the Perrin for many years at that point, I do wonder if there isn't an issue here.

 

And yeah Rebourne. All of this peeking around on VD for me is because I was drooling over those torque levels.

[joeleodee]

jcole, what is your full mod list? Is it posted and I just missed it? The plot I posted above comes from a vehicle with an external wastegate and manual boost controller. Both those things can help with spool. I want to say he's running an ELH, but I am not 100% on that.

 

Anyway, that Tomioka should NOT be spooling at the same rate as my big laggy AVO450. That is tuned for 24psi peak and by 4k, it's hitting 20psi with peak coming 200rpm later. Even in the sticky hot weather it hits peak by 4400-4500rpm. I'm also running an EWG and hybrid boost control setup. Even still, something is cooking that turbo. Whether it's the hybrid nature of the turbo itself or something else, I don't know.

 

I am enjoying this thread though. Lots of information and much more yet to come.

[jcole05]

Joe - thanks I am really enjoying this thread (and this experiment I have going on) and appreciate others helping to keep it going.

 

Haven't posted full mod list post-engine build but will get it listed soon - want to peak at my invoice to be sure I get everything on there and remember what was done with the Tomioka install besides going topfeed w ID1200s.

 

I can tell you this-the Tomioka spool was identical (I mean essentially at least-I can plot a pre-build VD of that too) pre and post engine build. So when I post my current full mod list, it will be important to remember that a lot of changes were made that did NOT really affect spool. So I am still concerned about a leak or other problem.

 

I mean look at the slope of my boost on that GT28 plot!

 

But for the 16g I had the pretty basic list of a catted DP (CNT), aftermarket UP (can't remember company), COBB CBE, Grimmspeed EBCS, Perrin ELH, Torque Solutions TMIC, BNRr 18g with DW850s and an Aeromotive 360 pump.

 

Of course I have other changes too like a wideband, mild brake upgrades, cubbyhole boost and AFR gauges, an FX350 clutch, etc. which aren't power / spool related.

[jcole05]

 

Ok here is a VD of my car with the GT28 pre-engine build. It spools slightly faster that post-build but not by much.

 

The only changes made from the mod list I posted just a bit ago for the 16g included: TGV deletes, the already mentioned change to top-feed ID1200s, a Tomioka FPR, a Tomioka AOS, a Tomioka turbo inlet and an AEM CAI. So the VD chart above includes these mods.

 

THEN, with the engine build, we did:

CP 100mm forged pistons at 9.0:1 CR

Manley H beam rods, ACL rod bearings

Ported and polished heads

Manley +1mm valves

GSC Sti S1 cams 268/266

ARP head studs

Gates timing belt w water pump

Sti 11mm oil pump

LIC adjustable timing belt

NGK one step colder plugs

Killer B Oil pan

THE INFAMOUS TOMEI UNEQUAL HEADER

Group N mounts

Koyo Radiator

Thermal zero turbo blanket and uppipe blanket

 

So the earlier Tomioka VD had THESE mods.

 

Now, we are doing FMIC, a six speed swap, the carbon fiber drive shaft, and an EWG (turbosmart 45mm). So all of the real time data from this turbo shoot off also includes these changes.

 

Hope that makes sense. I can clarify as needed. I also can post REAL dyno plots for the Tomioka both pre and post engine build. I never got the 16g on a dyno.

[Rhitter]

Have you looked into the KillerB spoolinator? From the threads I have read it might give you what you want.

 

http://forums.nasioc.com/forums/showthread.php?t=2622327

[LatentWagen]

Yea that particular GT28 looks like it's spooling like a big GT30... A properly setup GT28 should be spooling at least 1000rpm sooner than the above plot. Rotated GT28, E85, and lots of boost will get the job done (so will the turbo below, wow, nice!!).

[jcole05]

 

Final 26psi tune on the 10cm hotside Dom2.5xt-r. Comments? I am loving the thought of having this kind of power and we've still got a whole lineup of turbos to test!

 

I still wish the peak was a bit more to the left based upon joe's plot, some data available on the EFI dyno database, etc. However, wow...a real 450wtq. And this is corrected. Based upon today's uncorrected run they tell me the whp was about 485 and wtq about 465. It is 48 degrees today here with 77% humidity. Finally, they showed me the boost curve (didn't get one to take home and post). Between it and the torque curve, I don't think I can possibly have a boost leak. Seems to be taking time to get into the boost building phase but then goes up in a hurry.

 

Open to thoughts about spool then (not ignoring previous post about Killer B Spoolinator but interested in any ideas why my car seems to like to be on the laggy side in terms of initial turbo spool).

 

Finally, their Dyno Dynamics dyno runs about 230-240 for a stock STI, about 175-180 for a BRZ.

[need bb]

Both turbo results show spool later than I would expect. With the Dom2.5I would expect to see around 20psi around 4000 to 4200RPMs. With my TD05-20G I see 20psi around 3500RPMs. Has your shop does a boost leak test?

[jcole05]

Hi need bb. No. I spent about 20 minutes there today discussing the specific issue of the relatively slow spool on my car and said at least three times "now you're SURE I don't have a boost leak, right."

 

They pretty much blew the question off...a bit like I was insulting their knowledge level (and I admit I am still a bit noobish about most car related issues compared to the really serious contributors around here, and they know this).

 

So no, there has been no formal boost leak test. Admittedly, with the way the Dom2.5 built boost once it got going, I tend to think that if I had a significant leak the boost increase would be flatter (more like that Tomioka which clearly has issues in my current configuration). But this remains an unknown.

 

About to post the plot from the Dom1.5xt-r 8cm hotside, if their cell phone pic will work for posting. If I'd read the Topspeed data before we ordered the turbos, I'd have gone with the 10cm hotside, but oh well.

[jcole05]

 

Sorry for the poor quality, but it was nice of them to snap a cell phone pic and forward it along. I haven't studied the side by side with the Dom2.5 but this clearly seems a bit less 'peaky.'

 

However, I admit that the final values on the 2.5 of >450 wtq and whp are making the side of me that *can't* let go of focusing on 'the numbers' drool a bit.

[LatentWagen]

Both turbo results show spool later than I would expect. With the Dom2.5I would expect to see around 20psi around 4000 to 4200RPMs. With my TD05-20G I see 20psi around 3500RPMs. Has your shop does a boost leak test?

 

Could just be this DD dyno.

 

That 1.5XTR w/8cm looks really good. Doesn't quite hit your number, but it'd probably worth the trade-off in terms of street-ability.

[joeleodee]

Interesting results. If you went with the 10cm hot side with the 1.5, the numbers would look even closer to the 2.5. Both promising results and I believe fine tuning would get you closer to what you're looking for. The shop seems to be slapping a quick tune to get through the process, but hopefully whichever you decide, they'll make a few more tweaks to really optimize the build.

 

Btw, what was the peak boost on the 1.5?