thenoxus1

Okay Guys, I have a mildly built NA GSR and only made roughly 163whp, which is low. I know I need a test pipe and intake manifold, but does anyone have any good manifold suggestions? I'm emphasizing lower portion of the curve here, I like my power down low. Below are my specs, and the issues my tuner noticed.

OEM GSR B18C1

Stock Cylinder Head
OEM Valves
Supertech Titanium Retainers
Supertech Dual Valve Springs
Supertech Seals/Guides

Skunk2 Pro Series Stage 1 Camshafts with seamless crossover
AEM TruTime Polished Cam Gears

Block:

Stock B18C1
.25 oversize bore
OEM Honda JDM P30/B16 Pistons .25 over
Stock GSR Rods
GSR Crank
ARP Head Studs
ARP Rod Bolts

All OEM Honda Gaskets
OEM Oil Pump
OEM Acura RDX Injectors modified for B series

AEM Short Ram

AEM Digital Series Oil Pressure Gauge
Innovate MTX-L Digital Controller Wideband Gauge with Bosch O2 Sensor

Exhaust
Custom 2.5" into 3" Back Custom High Flow Cat Converter by SMSP
3" Apexi N1 Muffler
PLM Tri Y Header Narrow Tube at 2.5" Collector
Custom Bent 3" Piping by SMSP

Stock Intake Manifold
Stock Throttle Body

Prothane/Energy Suspension Mounts all around


Expected Compression Ratio 11.52:1

Dyno Tune on Hondata S300 in a P28



Here's my tuners notes:

1. Oil pressure was initially very low. I had installed the digital AEM gauge and was monitoring pressure through the gauge. With the 30 wt break in oil I was seeing 70-80 psi on cold start and 10-15 psi at idle (normal). I was expecting to see more due to the thicker oil. When I did the engine break in on the dyno I flushed the oil out and put in 5w30. The oil pressure was dropping to "0" on the gauge after a few pulls on the dyno. I was very concerned so I pulled the oil pan down to inspect everything; however nothing seemed out of place. I installed an s2000 oil filter and used 10w30 wt oil (what I usually recommend to use) and oil pressure was higher, but after a few dyno pulls the idle oil pressure would drop to 1-2 psi at idle. I pulled the valve cover to inspect the cams and valvetrain and saw no odd wear patterns from oil starvation (which would happen very quickly with no oil pressure in the head). Knowing my past bad experiences with AEM gauges (the brass sensors not reading correctly) I decided to swap in a stainless version of the pressure sensor (same calibration scale and psi). The stainless sensors are more stable and seem more accurate from what I have seen. Sure enough the oil pressure was immediately reading 8-10 psi after a few dyno pulls, as well as 10-15 psi higher everywhere. So your brass sensor that was included with the gauge is not accurate.

3. Power output is very low. It made 163 whp / 120 tq. Engine compression is 225-230 psi in each cylinder, cams are degreed and valves are lashed correctly. The engine does not smoke or consume oil. I tuned with the secondaries on the intake manifold open and closed, and leaving them completely open/disconnected yields the best torque/power. I suspect the low power output from the cat, stock intake manifold and short ram intake that is installed. Further the headers that you are using have a bad dip at 6-7k rpm range, which is a characteristic of the header design. The power the engine is currently making is a little more than a stock gsr with bolt on's/tune makes on my dyno.

5. The cylinder head appeared to have signs of oil starvation, as well as some discoloration on the crank. At some point in the engine was starved of oil, or had oil contamination. The crank measured ok, and the head appeared to be ok when the cams were installed. I just wanted to make you aware of this.



Anyone have any thoughts/experience?

DarKStaR5

I think the intake is the least of your worries

thenoxus1

The issues were pre rebuild, so what do you think I should look at first?

Charlie Moua

iTrader: (3)

hahah
ditto...



figure out your oil pressure issue. once you fix that, go back for retune.
Changing out your IM won't magically solve your oil pressure issue.

Good luck

thenoxus1

Sorry, was under the impression it was a bad gauge reading. New oil pump/pickup etc

OH_1fstgsr

iTrader: (2)

First you need to get to the root cause of your problem. And it is not your manifold.
My GSR with an OEM GSR manifold and GSR Cams made 170-175whp. With the troubles you where having with oil your car would have had trouble getting into VTEC and staying in VTEC.
How did you get your P28 ECU to work you IAB's? Your would have needed a relay and maybe even some wiring changes to get the ECU to operate the IABs.
Are you able to post up your dyno?

95eggsr66

this should be somewhere around 195whp/145wtq roughly

fungus mungus

195whp/145wtq? I don't think so. With an LS crank, maybe. Not with the stock GSR stroke.

Those numbers aren't *that* low. I was getting 172whp/120tq on my GSR w/ported head and S2S2 cams on a low-reading Dynapak. The OP is running S2S1 cams. I don't see that his numbers are that out of line. What dyno was the tune done on?

Also, the OP stated that the oil pressure "problem" disappeared when he replaced the sensor. Thenoxus1, are you staying in VTEC during the dyno pulls? If you are, and assuming you have a functional VTEC oil pressure sensor, oil pressure is not a problem.

fm

95eggsr66

11:5:1 gsr with a built head should be over 180 regardless

stock gsr's make 180

fungus mungus

Stock GSRs on my planet do not make 180whp. They make about 140-145. Again, the OP hasn't stated what dyno he's tuning on.

fm

DougNuts

Brand of dyno? On some of them, 163hp is great.

thenoxus1

Sorry guys, finals are raping me. It was tuned and blueprinted by Jeff Evans of Evans Tuning. It was tuned on a Dynapack Dyno. Oil pressure appears fine and it hits vtec, remember these cams have a seamless crossover as well. Secondaries were killed/opened for best power. Jeff said oil pressure is fine, it's the sensor reading as stated above.

He's leaning towards the cat and a stock manifold hurting my flow. Remember the head was not ported. Seems to cut out after 7, which he says is tri y header typical. I'll get the dyno in a few days and post up when I can.

thenoxus1

Also, stock GSR makes 180 at the crank not at the wheels, to whoever said that.

thenoxus1

From Jeff

"The engine oil pressure is fine, the pressure sensor that comes with the gauge is junk. I changed it out with a stainless version and instantly had 10 psi and idle and normal operating oil pressure. The oil pump and bearings were brand new on the rebuild, they do not need to be replaced. There is nothing wrong with the engine. "

nealnanoHX

Your setup should be around 180-190whp 125-130lbft on a good tune. So your numbers are low for sure. Glad to see you did not have a oil pressure issue, that it was just a bad sensor. Your stock IM is not a major issue and IMO is better for a street car than most aftermarket manis. It has good low end tq and is decent in the top end. An ITR TB or a 68mm TB and a port match will help out but I would look to the tune for the low power. My LS Vtec with stock B18B1 bottom end and B16 cams made 161whp 125lbft after a tune.

fungus mungus

^ Your dyno may read a little lower or higher than the OP's. Also, the longer stroke of the LS crank will give you more torque than a GSR block with stock crank. 120-125 wtq on that crank is all I would expect. I think 180-190 on those cams really optimistic, even with a better header or different intake. S2S1 tuner cams have similar profiles to CTR cams. 170-175 is about all I would expect.

fm

thenoxus1

Hey fungus, they're actually pro1s. I am going o ride this summer as is. Then I'll retool and retune this winter probably.

nealnanoHX

Dyno was a Dynapack, they are known to be very accurate.
Even with CTR or ITR cams the 180whp is not out of reach with the right tuner. I have seen stock GSR's lay down 180whp with bolt ons.

fungus mungus

^ again, I call BS...I just don't see any stock GSR is putting down 180whp with without cams and bolt ons. Well...maybe on Church's dynapak...and we know how accurate that is.

fungus mungus

Oh, OK, I saw in the first post "Skunk 2 Pro stage 1" cams and read that as the tuner 1 series since as the pro series are usually referred to as "Pro 1", Pro 2", etc. Reading fail on my part. In that case, I agree with you and the others that your numbers are on the low side...180-190 is attainable on those cams with your comp.

Are you running a new timing belt? Is there any chance the timing belt slipped a tooth? I've seen stupidly low numbers in a similar setup that had the tuner stumped and it turned out the timing belt was stretched. Evans has a good rep, so he's probably aware of this possibility, but I bring it up just in case. Given your comp numbers (230) this probably isn't the case but...

If the IM is to blame, it should be pulling a lot of vacuum in the upper RPMs...did Jeff say this is the case? If it is, then a better flowing IM would improve things. I had that same dip with my header...maybe a header swap, dropping the cat (or going with a high-flow bullet cat) along with an IM swap would help things.

You might have Jeff try doing a dyno pull open header to see what your graph looks like. If your IM is the bottleneck, it will will be.

fm

m_shake

Beat me to it!!

95eggsr66

unopened b18c gsr
intake/68mm tb/skunk2 im, ebay header, 2.5" test pipe, 2.25" catback tuned with crome 181/136 on a dynojet

make the 1 hour drive to psi proformance in lansdale, pa and steve will give you much better results

fungus mungus

^ Nice graph...vehicle weight and 1/4 mile trap speeds please. Those number seem pretty optimistic for bolt-ons, particularly torque. I made 184whp/120 tq on a dynapak with S2S2 cams and similar bolt-ons. A week later, I took it to a shop with a dynojet and the baseline (same tune, different day, similar weather) came out to 192/130. This is all to say that different dynos read differently. At the end of the day, trap speeds at the track don't lie.

fm

95eggsr66

13.9@98 with a 2.117 60'
its in a gutted eg coupe, I havnt weighed it in a while but I wanna say 2450 with me in it

nealnanoHX

I said with bolt ons, no cams or internal work. With the right bolt ons and a good tuner 180whp is very possible on a GSR motor.