Post a picture you took today.
- Thread starter tixer
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I took it apart and painted the reflector. I was testing it out for those photos, with and without the red lens on.
driller
El Presidente
What are your thoughts Driller? I looked at your dyno run in 2011 and it was 324hp peak but had that same dip at 5200-5400rpm. I know you had compression concerns last year. With the odbII now and a new tune I would spend some data logging.
From your build thread I know you expected more, have you seen any dyno numbers from combos like yours?
I know you did a fuel pump upgrade and you're running different coils now.. Kinda narrows the field a little.
I've seen a dip in the power curve like that before... Aside from tire spin and belt slippage on a blower.
I would double check the air/fuel and make sure it was a nice clean line. (Not sure if this was just a dyno run or a tune and dyno run) could be that gen1 intake but I would think it would continue to choke beyond a certain rpm.
If the air/fuel looks good take a good look at the timing curve, it almost looks like it is pulling timing (knock sensor function?)
If all that checks out I would suspect mechanical and I would start with the cam timing.
I checked the NA HP list over on corral and it looks like you're short about 100hp
driller
El Presidente
First thought is that this is the most expensive 300 HP motor I've ever seen. If it doesn't do what I think it should soon, I guess we will have to bite the bullet and have it torn down and new rings installed.
Beyond that, I was impressed with being able to datalog while on the dyno. It showed me the direction I need to go.
The A/F was targeted for 12.6 and was dialed in pretty flat throughout at WOT. I can tweak it from there at future track sessions. I'm happy with the way the AFR is now to be able to run at the track. The top end under load was probably 20% lean when we started.
I am still getting some funky STFT numbers at low rpms. I'm going to try another set of O2's just to be sure I didn't get a bad pair. I will be pulling the spark plugs and checking them and replace them with a fresh set of 12C's. I may do a quick check again for compression numbers.
There still may be issues with the converter? It was unclear if it was holding 100% on the dyno. I should be able to datalog at the track and quickly figure out if it is slipping or not. I can also look at the data logs from the dyno as well.
The good news is the high rpm stutter we had before is gone. The OBD2 PCM allowed the car to run the rpms it wants. We started with 6000 rpm and it was still making power. We then went to 6500 rpm and the power was still building. I then went to 7000 rpm with the limiter set at 7200 and we finally saw power peak around 6900 rpms. Of course now this means I will have to go back and rework the shift points to maximize acceleration.
The biggest observation was logging LOAD on the dyno. The load peaked early, around 91% at 5200 rpms and faded from there to low 80 percentile range at the end. I'm no expert but I don't believe that's the way it should be. My earlier suspicions on the current intake appear to be correct. I had been working on getting a head/cam/intake swap but my patience is wearing thin (it was supposed to be done months ago). I may take one of the Cobra intakes I have and do a ported/short-runner intake or just go with a sheet metal intake like the MMR RTS model.
Spark - we dialed back the spark until the A/F was dialed in and when we added spark back I believe we ended up settling for 27*. There may or may not be more to gain there from track testing/tuning.
Other than what you see posted on Modular Performance and the Corral, I have not seen any dyno numbers from builds such as mine. At first glance, I suppose you could say I'm 100 HP shy of where it should be but I don't think my combo is quite typical. My goal was to dial in the A/F with load at the dyno after the OBD2 conversion and I did not have any preconcieved expectations for any particular dyno numbers.
But hey, it can only go up from here.
Ford nut
New member
:thumbsup:First thought is that this is the most expensive 300 HP motor I've ever seen. If it doesn't do what I think it should soon, I guess we will have to bite the bullet and have it torn down and new rings installed.
My thoughts were headed towards a open style intake, but I am no expert.The biggest observation was logging LOAD on the dyno. The load peaked early, around 91% at 5200 rpms and faded from there to low 80 percentile range at the end. I'm no expert but I don't believe that's the way it should be. My earlier suspicions on the current intake appear to be correct. I had been working on getting a head/cam/intake swap but my patience is wearing thin (it was supposed to be done months ago). I may take one of the Cobra intakes I have and do a ported/short-runner intake or just go with a sheet metal intake like the MMR RTS model.
But hey, it can only go up from here.
Frustration must be at a high level.
Good luck with it I think you have a good plan.
The torque converter is a good suspect for that dip in the graph too.
27* timing seems like a lot on pump gas (if your high comp) next time you data log set the knock sensors as a data point. That is if you still have them on that motor.
A friend of mine had the same problem after he went to stage 3 cams and ended up eliminating the knock function in the tune. Extra lift and duration must have created the right freq from the vibration to trip the sensors. 1k hz I think, he ended up eliminating the knock function. The way it was it didn't matter how much timing they commanded it seemed like it would take more, in reality the computer was pulling it on the knock function.
I agree on the intake, although I have no proof as to what a gen 1 will flow.
I thought you had a big cam set up and fox lake reworked heads?
27* timing seems like a lot on pump gas (if your high comp) next time you data log set the knock sensors as a data point. That is if you still have them on that motor.
A friend of mine had the same problem after he went to stage 3 cams and ended up eliminating the knock function in the tune. Extra lift and duration must have created the right freq from the vibration to trip the sensors. 1k hz I think, he ended up eliminating the knock function. The way it was it didn't matter how much timing they commanded it seemed like it would take more, in reality the computer was pulling it on the knock function.
I agree on the intake, although I have no proof as to what a gen 1 will flow.
I thought you had a big cam set up and fox lake reworked heads?
And if anyone is interested in a NA mod motor HP/torque list this is a good one. http://forums.corral.net/forums/svt-dohc/515518-official-4v-naturally-aspirated-hp-tq-list.html
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driller
El Presidente
Indeed it is.
Yes it was in locked in 3rd during the pull but after looking at the datalogs, either the converter was not locking or the N/V is out of whack. The datalog says 107 mph at 7100 rpms with 4.30 gears and 255/55-18s!?
No knock sensors are on this motor.
I don't have any proof what the intake manifold flows other than I don't believe the stock Cobra intake would flow much more if any. Now a ported/short-runner intake manifold may indeed flow more. It would cost probably $1200 for a good PSR Cobra intake vs. $1500 for the MMR sheet metal manifold. :eek-large:
Yes, the cams are relatively big (0.504" Lift with 234*int/240*exh duration at 0.050"). The heads are Stage 3 B-heads from Fox Lake.
https://www.youtube.com/watch?v=rd7e77xivvA&feature=youtube_gdata_player
Took her out for a spin with the good weather, and took a buddy with me. Camera work Sucks, but the sound is all there.
Took her out for a spin with the good weather, and took a buddy with me. Camera work Sucks, but the sound is all there.
