boosted hybrid

I finally got a chance to dyno my car with the GT28rs installed. After ruining my brakes at Watkins Glen, it took nearly a month to get together the Legend GS front brake conversion and machine everything to fit, which delayed getting the car tuned with the new turbo. Here is the dyno graph comparision:



The only items that were changed on the car was the intercooler from the 11x20x3" FR to the 8x20x3". The larger volume of the 20x11x3" core was overkill for my application and desired power level for the car. Everything else was retained. Tuning was at 11-12psi, which is approximately the same boost level the gt3071 was at (11psi). A/f was 12:1 under boost, engine coolant temp was started at 185-190 in each dyno run, IAT's were about 25 degrees lower than the gt3071 pulls, vtec point lowered to 3500 rpm (gt28rs tune) from 4200 rpm (gt3071 tune) and the timing curves were optimized for both turbos.

The results are amazing to say the least. This is exactly the powerband that i am after for road racing. Driving the car on the street is insane, tons of low, mid and high end power. Peak power is coming in earlier around 7500-7600 rpms, which is welcomed especially on a road course. The peak torque gain was 58 ft-lbs, with gains found almost everywhere else in the powerband.

BTW, this was using the gt28rs not the gt2871 version. The turbine housing was the atp "drop in" .82a/r t3 housing. The internal wastegate was removed.

093turbo16

iTrader: (2)

hey man, that is some interesting information. Glad your car is running again.

B18C1CYA

wow jeff that is sick, looks like you have the killer combination going

0project dc2

iTrader: (1)

NICEEEEEEE !!!!!!!!! u got MORE POWER by goin smaller...


i got the GT2871RS for my car but with tha .63 A/R T3 drop in style housing.

thats EXACTLY the type of powerband i was going after. im glad i got my 2871 instead of the 3071. i was just afraid that i'd lose top end power but you put my worries to rest...

btw jeff woudl you be willing to dyno smaller ic piping vs larger ic piping? im curious as to see if there are any types of gains from that too

Def

You guys use absolutely HUGE turbines on these small **** compressors! The SR20DET community typically likes the 0.64 A/R T25 hotside on the GT2871R. So far there have been a few dynos of 370rwhp at 18 psi, so it can obviously flow that much. That GT28RS is also spooling up way late in that dyno above compared to what I'm used to seeing(probably due to the turbine). What size engine is that ? On 2.0L SR's, GT28RS can hit 18-19 psi at around 3800 RPM if tuned right. The 0.64 A/R GT2871R will make 18 psi by 3700 RPM or so.

A 0.82 A/R T3 housing is larger than what the 2.4L KA guys run on their T3/T04E's!!! They typically choose 0.63 A/R T3's with a Stg3 wheel.


I think you guys could easily step down a size in your turbine housing and pick up a few hundred RPM in spool and not notice any HP difference up top.

0project dc2

iTrader: (1)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Def &raquo;</TD></TR><TR><TD CLASS="quote">You guys use absolutely HUGE turbines on these small **** compressors! The SR20DET community typically likes the 0.64 A/R T25 hotside on the GT2871R. So far there have been a few dynos of 370rwhp at 18 psi, so it can obviously flow that much. That GT28RS is also spooling up way late in that dyno above compared to what I'm used to seeing(probably due to the turbine). What size engine is that ? On 2.0L SR's, GT28RS can hit 18-19 psi at around 3800 RPM if tuned right. The 0.64 A/R GT2871R will make 18 psi by 3700 RPM or so.

A 0.82 A/R T3 housing is larger than what the 2.4L KA guys run on their T3/T04E's!!! They typically choose 0.63 A/R T3's with a Stg3 wheel.


I think you guys could easily step down a size in your turbine housing and pick up a few hundred RPM in spool and not notice any HP difference up top.</TD></TR></TABLE>


the car above is a bone stock 1.8 L gsr motor


the thing is, with the GT technology you can easily go with a bigger turbine housing cuz the turbine wheel is so much more efficient, so you can gain your top end without losing out on the great spool gt turbos produce.

boosted hybrid

Honestly, SR guys can use the lower end power more efficiently since they are RWD, and traction is just better on those chassis. As it stands right now i am fighting putting all the power to the ground in the lower rpm levels. The turbine blade that is in the turbo is whatever garrett engineered. The housing size really isnt that large or laggy, especially for a honda. SR engines also peak their VE much sooner than a honda with the stock IM and cams.

Here is a quick clip that Eluder200k made:

http://www.evans-tuning.com/pics/fullrace/jon.jpeg

birz

a clip??? to me it looks more like a picture, not a clip.

4-banging

How does the gt28rs compare to the sc61? Looking on your graph, the green line is the "new" powerband? What psi are you getting those #'s at?

Thanks in advance

PM-Performance

I am assuming the Blue line is the new turbo? If thats the case, thats a sick change up. Low end power looks to be killer, more of a flat response and not peaky like with bigger turbos. . Just sucks how the power and tq drop off uptop. But you really dont need it up top i guess. Im used to my Drag racing lol
Let me know when you guys go to an event next.Ill roll up with yall

SL0WEGG

thats pretty neat. the powerband changed so much. perfect for the road course. for you!! oh. i think u got the wrong link for the vid

B18Flip

wow awesome results Jeff

JDogg

https://honda-tech.com/zerothread?id=1011420

good stuff... theres my semi comparison between gt28rs and gt3071r

moral of the story... gt28rs&gt;gt3071r

on my dyno's the power fell off b/c the boost was falling off on the top.. .cheap *** MBC

0project dc2

iTrader: (1)

.......... wheres the video !?

ladysman

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by project dc2 &raquo;</TD></TR><TR><TD CLASS="quote">.......... wheres the video !?</TD></TR></TABLE>

http://cs.widener.edu/~epanek/GT28RS.mpg

racinskittle

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by itr206 &raquo;</TD></TR><TR><TD CLASS="quote">I am assuming the Blue line is the new turbo? If thats the case, thats a sick change up. Low end power looks to be killer, more of a flat response and not peaky like with bigger turbos. . Just sucks how the power and tq drop off uptop. But you really dont need it up top i guess. Im used to my Drag racing lol
Let me know when you guys go to an event next.Ill roll up with yall</TD></TR></TABLE>

I think he's using the green one but im only 90% sure on that He mentioned peak power at 7500-7600 so i was guessing the green was the one.

0project dc2

iTrader: (1)

vid here

http://cs.widener.edu/~epanek/GT28RS.mpg

but .. we need an in car video !!!

Phil Koury

Heres a smaller version of that graph, Honda-Tech is great for ruining big pictures... at least you can somewhat make out the numbers in this one and see the lines a bit clearer



Evan didn't get in car video last night, but Lime Rock is on Monday

PM-Performance

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by racinskittle &raquo;</TD></TR><TR><TD CLASS="quote">

I think he's using the green one but im only 90% sure on that He mentioned peak power at 7500-7600 so i was guessing the green was the one.</TD></TR></TABLE>

its gotta be the blue one for the new turbo. Only makes sense with the powerband of a smaller turbo. more low/mid power less up top.

SoulEdge

Why is the torque falling off by ~40 ft/lbs after 6300 rpm? I thought w/ the .86 a/r it would be able to sustain it through 8k. And it's only pushing 11 psi too...

Still, the newer powerband looks so much better than the old one

Eluder200K

Pete, the dotted lines are the 3071 and the solid lines are the 28rs. Green is hp and blue is torque, i guess it's hard to see the color of the dotted lines but they are green and blue just like the solid lines.

The 28rs gained everywhere in the powerband under 8000rpm's in hp and torque.

antisport

awesome results I like the idea of people not using over kill parts!! and look you gained great job

PM-Performance

WOW. then im really stumped. i thought the Blue dotted and straight were for the RS and the Green dotted and straight were for the 71.

That is a very interesting result then .
I though he would have just picked up low/mid hp and tq and fell off up top and with the 71 had less down low and just more peaky up top. Maybe ive been thinking allwrong all this time with turbos. Damn

4-banging

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Eluder200K &raquo;</TD></TR><TR><TD CLASS="quote">Pete, the dotted lines are the 3071 and the solid lines are the 28rs. Green is hp and blue is torque, i guess it's hard to see the color of the dotted lines but they are green and blue just like the solid lines.

The 28rs gained everywhere in the powerband under 8000rpm's in hp and torque. </TD></TR></TABLE>

If thats the case then, WOW! At 4500rpm you gained about 50 more whp and 60 more ft/lb of torque. All this at a measily 11psi

The more I look at that graph. . .everything just keeps climbing past the 71

boosted hybrid

The gt28rs is the solid lines, the dotted lines are the 3071. Sorry about not stating that upfront.

The turbo has amazing response. I got to drive it a little more now that the road are dry around the shop. I have another HPDE event this coming monday at Limerock, look for another video.