Boostin_GSR

So there were alot of people on here that told me how bad of an idea or how against they were on doing a stroker turbo motor. I though I'd be a little different and do it anyways. Mods are 81.5mm bore (stock sleeves), 95mm stroker, pistons are 8.5:1 cr, RLZ Enginering Head with skunk2 valvetrain and Skunk2 Stage 2 Pro Series cams, with a peakboost turbo kit. Results are 321 whp with 201 wtq at 9k RPMS. The biggest kicker is...................................that's on my 4.5 psi wastegate spring!!! For the non believers I'll be posting up the dyno sheet in a little bit, I'm at work right now.

Schister66

either that wastegate is creeping or you're running a GT4294R.....i'm waiting for the graph and more details on the setup though

turbosi03

Few things don't seem to make sense such as previously mentioned high whp on 4psi, unless you have a boost controller. Also when I had my b16a stroked bored to 2.0L it put down 350whp @ 325tq so I would think you would have closer tq numbers to your hp #'s...

What turbo?
Interested in seeing the dyno

Schister66

i just dont see how those numbers are possible on 4psi unless the turbo is WAY to big...in which case, i'll live w/ a little less power and actually have a powerband. Another thing, you need to crank that boost up!! I'm making 315/216 on my STOCK GSR. So far, your stroker build has yielded less torque than stock.....

preludestud11

iTrader: (1)

I agree that torque is not matching up to the hp numbers.

boostfeen

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Schister66 &raquo;</TD></TR><TR><TD CLASS="quote">i just dont see how those numbers are possible on 4psi unless the turbo is WAY to big...in which case, i'll live w/ a little less power and actually have a powerband. Another thing, you need to crank that boost up!! I'm making 315/216 on my STOCK GSR. So far, your stroker build has yielded less torque than stock.....</TD></TR></TABLE>

..its prob. more like a SC61 and not at 4psi either...cause i can't see a 42r on a stroker setup with stock sleeves. i can see a big window in that block,lol

Boostin_GSR

I'm running the T3/T04E .60/.63 turbo that comes with the peakboost kit. The kit also comes with a 38mm Tial wastegate. Options for springs are 4.5 psi, 6.5 psi, and 9 psi. We checked on two boost gauges and they were reading 5 psi. I'm going to get on in a second and post up the dyno, I work at a dealership and I've got a car right now. Oh and by 1500 RPMS I'm already building 2 psi of boost. I'm in full boost before Vtec even kicks in.

Dunc

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Boostin_GSR &raquo;</TD></TR><TR><TD CLASS="quote">Oh and by 1500 RPMS I'm already building 2 psi of boost. I'm in full boost before Vtec even kicks in.</TD></TR></TABLE>

2psi by 1500? Does a T25 even spool that fast? haha that's kinda funny since you're boosting 300rpm's above where I idle.

njn63

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Boostin_GSR &raquo;</TD></TR><TR><TD CLASS="quote">So there were alot of people on here that told me how bad of an idea or how against they were on doing a stroker turbo motor. I though I'd be a little different and do it anyways. Mods are 81.5mm bore (stock sleeves), 95mm stroker, pistons are 8.5:1 cr, RLZ Enginering Head with skunk2 valvetrain and Skunk2 Stage 2 Pro Series cams, with a peakboost turbo kit. Results are 321 whp with 201 wtq at 9k RPMS. The biggest kicker is...................................that's on my 4.5 psi wastegate spring!!! For the non believers I'll be posting up the dyno sheet in a little bit, I'm at work right now.</TD></TR></TABLE>

You have a motor with more stroke than a stock b18b, almost same bore, but you make significantly less torque at a similar hp? Something isn't right.


Modified by njn63 at 1:53 PM 9/11/2007

0morgan@synapse motorsport

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by njn63 &raquo;</TD></TR><TR><TD CLASS="quote">

You have a motor with more stroke than a stock b18b, almost same bore, but you make less torque at a similar hp? Something isn't right aka your story is madeup. </TD></TR></TABLE>

i noticed the same thing, but the turbo is on low boost, and its got a ton of headwork, pro2 cams and reving out. i would think the stroke to be more evident with a lot more boost.

still doesnt make much sense though...

any dyno graph?

Boostin_GSR

.nate

Looks like the boost isnt staying at 4psi lol

Dunc

Besides it being a roller coaster of a powerband haha, it looks like boost creep starting around 7000rpm. The torque shouldn't be increasing like that...it should have been flatter and holding closer to the 180ish mark.

Boostin_GSR

Motor is just tuned off of the wastegate, boost controller isn't even turned on or nothing. I'm running the skunk2 stage 2 pro series cams too. What do I know though, I'm no tuner just a funder

0morgan@synapse motorsport

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Boostin_GSR &raquo;</TD></TR><TR><TD CLASS="quote">Motor is just tuned off of the wastegate, boost controller isn't even turned on or nothing. I'm running the skunk2 stage 2 pro series cams too. What do I know though, I'm no tuner just a funder </TD></TR></TABLE>

just because its on the WG spring doesnt mean boost isnt rising. if the wastegate cant flow enough exhaust gases boost will begin to rise over the expected level.


edit: do you have a pressure plot from the dyno runs.

Boostin_GSR

Boost gauge must be broken then.

blaze the chemi

You've got...

boost creep!
boost creep!
boost creep!

You've got...

boost creep!

Wow...please get a good boost controller in there. for doing something different.

boosted k20

haha. that is crazy boost creep! fix ur boost issues and retune that car

highschooler

He might be boost creeping a little up top, it might happen too quickly to see while just glancing at a boost guage, but if he was creeping more than a few psi it would put him at more torque than 201ft/lbs...kind of weird on a 2.0liter.

njn63

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by highschooler &raquo;</TD></TR><TR><TD CLASS="quote">He might be boost creeping a little up top, it might happen too quickly to see while just glancing at a boost guage, but if he was creeping more than a few psi it would put him at more torque than 201ft/lbs...kind of weird on a 2.0liter.</TD></TR></TABLE>

It put out peak torque at over 8,000 rpm..

tannerLSt

yeah most stock gsr's make more torque than that with that much hp.... wtf... **** just doesn't add up. ya they run more boost than 5psi to get that power but it still doesn't add up.

tokesGTR

Just look at the graph and see why his torque is so "low". Before the boost starts jumping majorly at 7000-7200 RPM's he was on pace to make about 250 WHP and 180 WTQ. Boost starts creeping WELL after where peak torque is normally made, so the peak torque numbers are going to be lower for the peak HP number it made.

Either way, that wasn't at 4.5 pounds of boost, and if you could buy a stroker, why not get it sleeved? The extra side loading from the 95mm crank would definitely be making me a bit nervous on stock sleeves

rorik

What is the rod/stroke ratio on your motor? You need a tall deck dart block to build a stroker the right way...

BLK JDM

I have a friend that made 666whp and 562 w/ a 84mm bore and a 95mm Eagle Stroker crank w/ LS Pauter Rods, and 10.1 custom JE pistons. That was on a GT42R w/ a Full-Race topmount at 21lbs. The motor makes a beastly amount of torque. Those are the only #s I'll post. He wants to keep the higher #s under wraps.

dart2.2

well i also did a stroker/turbo with a dart block. it should be getting tuned in a few weeks. turbo being a pt74 with gts trim.