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Car is back on the Dyno. Without spoiling too much, the topend has been upgraded just a touch. Here's a picture from the dyno. Will post later with results and further details. Speculate as needed until then!
So since the first dyno, we've made some changes to the top end as well as opening her up with long tube headers. Even without a tune I could tell the engine was breathing much better. Forgot to get pictures of them before the ceramic coating and fitment. Needless to say, they were TIGHT. Flange on the passenger side had to be modified to get it to fit.
On to the money maker, the top end: Went with a set of Custom 223cc head from Mamo Motorsports. The guy is basically a god among men when it comes to heads. Set me up with a set that raised compression to about 11:1 static. Along with yella terra rockers, johnson short travel lifters, and 3/8" pushrods.
Also, just for funsies, while the heads and ITBs were off, had the ITB runners ported to get as much air in as we could. Left is before, right is after.
All reassembled, the car went back on the dyno and ended up making 473 whp and 437 wtq. Looking forward to rolling into her once the weather gets better!
Wow nice! Another 100whp and some nice trq! Looks like you may have got some increased rpm out of it too, which is always great, especially on this car platform.
What trans and rear end?
The tune looks pretty darn lean though and far too lean through many points in the rpm, any explanation on this? Notably, if you look at your power dip between 85-100mph, lining your afr up at that point it goes really lean into the 15's! Lean and corresponding power loss on dyno is not a good thing, that's how you blow motors.
Last edited by s2000Junky; 01-08-2018 at 10:31 AM.
Wow nice! Another 100whp and some nice trq! Looks like you may have got some increased rpm out of it too, which is always great, especially on this car platform.
What trans and rear end?
The tune looks pretty darn lean though and far too lean through many points in the rpm, any explanation on this? Notably, if you look at your power dip between 85-100mph, lining your afr up at that point it goes really lean into the 15's! Lean and corresponding power loss on dyno is not a good thing, that's how you blow motors.
Trans is T56 with the stock S2000 rear end. For now.
The passenger bank of cylinders is running lean and we believe it's due to the ITBs. Unfortunately HPTuners and the stock ECM won't let us make bank to bank fuel adjustments. The plan down the line is to upgrade the ecu to a haltech unit that will give more control so we can get things REALLY dialed in. Engine didn't seem to mind things running a touch lean since this dyno sheet produced the best numbers. The video of the pull above ended up being a hair less at 469whp. Also, he only ran one O2 sensor from the header (passenger side aka lean side) and one from tailpipe since the driver side O2 sensor had to be moved for the longtubes to fit and is subsequently unreachable while mounted on the car. I'm sure if the driver side would have been accessible it would fix that. I imagine it's reading a tad leaner than what the motor is actually seeing.
I imagine it's reading a tad leaner than what the motor is actually seeing.
Holy shite!! that would be typical of a tail pipe position, but accurate if taken at the test pipe/merge collector.
Well, I hope its richer then whats being shown. Doesn't sound like a safe scenario to me, when low 13's are max lean best on an NA engine. And a bit richer isnt a bad thing if the car gets driven hard. 15's is totally off the charts at WOT. Its an idle ratio. If your taking readings at the collector when all cylinders merge, this is the average afr if one bank of cylinders are running lean and one rich, which means you would have cylinders running even leaner then 15's. Ticking time bomb, in all sense. I must be missing something, because no reputable tuner would let you leave with the car running that lean with his name on it. Don't want to hear about you losing your motor a couple of drives from now so thought id say something from my observation.
Last edited by s2000Junky; 01-08-2018 at 08:41 PM.
Holy shite!! that would be typical of a tail pipe position, but accurate if taken at the test pipe/merge collector.
Well, I hope its richer then whats being shown. Doesn't sound like a safe scenario to me, when low 13's are max lean best on an NA engine. And a bit richer isnt a bad thing if the car gets driven hard. 15's is totally off the charts at WOT. Its an idle ratio. If your taking readings at the collector when all cylinders merge, this is the average afr if one bank of cylinders are running lean and one rich, which means you would have cylinders running even leaner then 15's. Ticking time bomb, in all sense. I must be missing something, because no reputable tuner would let you leave with the car running that lean with his name on it. Don't want to hear about you losing your motor a couple of drives from now so thought id say something from my observation.
It is! Idle is sitting at 14 and it's down around 13 at WOT. What I was trying to say was that the sensor placement was going to be exceedingly lean based on where they were and that the actual AFR's are much lower. It's all kosher
It is! Idle is sitting at 14 and it's down around 13 at WOT. What I was trying to say was that the sensor placement was going to be exceedingly lean based on where they were and that the actual AFR's are much lower. It's all kosher
08-03-2017, 06:53 AM
