BAD DYNO GRAPH IS ON SECOND PAGE

BETTER DYNO GRAPH IS ON 8TH PAGE link below.
https://honda-tech.com/forums/showth...5#post42675745

My GSR was with my tuner at the dyno and results are in 3whp gain peak and 22ft/lbs lost in the mid range. What a disapointment. I will post up the dyno comparison later tonight.
Old peak 184whp, new peak 187whp.

Old set-up
PnP'd GSR intake manifold
AEM GSR CAI

New Set-up
Performer X IM, port matched
AEM ITR 3" CAI
BPI 3" Velocity Stack

Everything else the same, listed below.

Exhaust
SMSP 4-2-1 2-1/2” Header
SMSP High Flow Cat 2-1/2” 300 cell
PTM 2-1/2” Custom Exhaust w/Vibrant Muffler

Intake
RC Engineering Ported GSR Throttle Body 70mm>64mm
RC Engineering Fuel Injectors w/clips 370cc

Block
USDM ITR Pistons (81.25)
USDM ITR Rods
(Compression Ratio ~11.6:1)

Head
DPR Stage 5 Port ‘n’ Polish
ITR Valves, ITR Springs, ITR Retainers, ITR LMA’s
CTR Intake Cam Shaft
ITR Exhaust Cam Shaft

ECU
Skunk2 OBD2a>OBD1 Harness with IAB control
P72 OBD1 ECU
Hondata S300

 

Now the question is what next?
Option #1
Back to the GSR Manifold, this time with larger butterfly valves, each 1mm larger, with more porting to match. With this I would need to some how get the ITR CAI to line up the TB location.
Option #2
Order BC3+ cams and see what that will do for me. These will work with my valve train and should help get some of that torque loss back in the mid range.

 

cams.

 

id hate to say it, but a lot of people told you so.

if you go back and look at the old thread i believe a lot of people were saying the manifold was not your issue.

the cams and exhaust are your weakpoint.

what type of dyno was it?

 

Not sure about the cam issues, ITR cams have gotten people to 190-200whp in ITR's with single runner manifolds. It has been shown in many cases the Performer X, out performs, the ITR and Skunk2 manifolds.

I really don't see how a SMSP header and a custom 2.5" exhaust is holding me below 200whp.

It was the same dynojet my tuner has always used.

So your saying I should put my PnP’d GSR manifold back on with bigger cams. Even though I maxed out the flow ability of that manifold.

 

Your best bet is going with a custom top plenum. You could cut off the cat and go 3" on the exhaust but that no fun to drive on the streets.

 

Did you check the engine before you went to tune.

 

I would also change to a t/b witout a taper. Maybe a 70mm straight thru and let the ported oem plenum due its job. Just portmatch to the plenum. That would be my first step in extracting more power from your setup

 

Were the numbers scaled relative to SAE corrections?

 

my butt dyno showed major gains in going from a PerformerX to a Skunk2 Pro manifold. Car pulled harder throughout the entire rev range with the skunk manifold.

 

I also vote go with the cams and then put an electric cutout on it. That is a pretty big intake manifold for a 1.8. sounds like its time to spray it and put it to use!

 

me personally since it's similar to the h22 intake mani i'd go back to what has the most tq. Tq will move the car better off the line and especially in the midrange.

I'd try and maybe spice up the gsr intake a little but don't overdue it with the porting. I'd talk to someone knowledgeable about flow dynamics to help achieve the most hp and tq from this setup. I'd also get rid of that cat and run 3inch exhaust.

I run 3inch exhaust and it's quiet i have 3inch moroso spiral flow muffler and a 3inch flow sound muffler in and out and it's quiet very quiet and no rasp.

 

were these dyno's done back to back? same dyno?

 

its not the header its would be the catback possibly being an issue.

if you dont have a cam to maximize everything else that could certainly cause a drop with that design of manifold if the cams are now the limiting breathing factor.

ive never personally seen a stock cam/PX dyno, mostly only seen them dyno'd with big cams ie pro 1's.

 

A performerX has been proven time and time again to out perform anything out there aside from a FULL custom manifold, he had no reason to not switch..

I know i would have done the same..
Its been proven also, that removing the butterflies outta the gsr manifold and some porting will produce excellent numbers.. honda knew what they were doing when they designed the gsr manifold.. however.

the performerX opens up doors for other things that need that flow.. I dont believe these numbers are right, i dont think i've ever heard of anyone actually losing that much tq from swapping manifolds unless something is hindering performance.

With that said, i'd try another dyno somewhere else just to gauge.
What is it, like 75 for 3 runs?.. there's no way a gsr manifold will make more power then a performerX on your setup unless its got some major port work done,aside from just alittle pnp..

I Believe in maybe a upgrade in cams is in order ...you have a "Stage5" ported head, i dunno what that means but if its a "stage5" your probably not flowing as much as you could..
i'm still baffled that you lost that much power from the pX.. thats just retarded.

 

k well, ya.. that doesn't help at all lmao..

 

The performerX manifold is specifically designed from the 1.6-1.9 liter motors.
There's a few dynos that show this manifold shitting on the following

Skunk2's pro series
IB customs manifold
itr manifold
AEBS

The victorX is made for serious serious 1.8 liters and more or so made towards 2.0+ liters that are all motor or turbo setups.
With that said, if you think this manifold is too big for this 1.87 liter setup, what do you think about the people who put victorX's on stock gsr's...?? LOL
The pX manifold is a good manifold, there's no reason it should lose this much power unless, its a motor problem...maybe with the head, the manifold requires the same porting.

 

Here are some pictures of the head.

 

Not back to back, but the same dyno.

Still waiting on the dyno graphs. I'll post them as soon as I get them.

I knew going to a single runner I would lose a bit in some areas maybe 5 at the most. I was hoping the Velocity Stack and larger diameter AEM CAI would help offset the loses.

 

Valve lash good. Oil checked. Didn't do a compression or leak down. Maybe loses a quart every 5,000 miles.

Yup.

 

I don't see y the engine would lose tq if there was a problem then i'd say he would have had one prior 2 the swap. Nobody really has done any dyno's vs the gsr custom intake mani it's a good test. The typer intake mani isn't the only thing that honda did right u know.

 

This is a good point most Type-R's I've seen with stock cams make around 110-115 for torque. I was at 135 and now dropped 20, I guess my numbers are now similar to Type-R's.

Your right, I don't think I have ever seen anyone just do a manifold change on a GSR, like I have done. Most people change the manifold, valve train and cams. To many variables at one time to get a good understanding of each ones impact.

 

because the dyno's were not done back to back it is really difficult to compare numbers even though it was the same dyno. you may not have lost as much as indicated on the dyno.

 

the only way to do a true comparison is to perform the test back to back on the same dyno using the same correction factors (or lack of correction factors). Logging the A/F ratio is also important information in any comparision tests. If you can't do the tests back to back in the same weather conditions, then your second best method would be to make sure both tests are done on the same dyno, using the same correction method. Uncorrected will not work that time.

 

and on a side note, get some real valvetrain and a real set of cams for your motor!