Degreed cams and lost torque below 2k room?

[RJCarp2]

*Title should say rpm, not room*

I just finished with a fresh rebuild. 97 Cobra engine with 11:1 compression and stock 97 cams degreed to 109 ICL and 114.5 ECL. From what I've read on here, a very common modification. From 3 to 7k, it runs great. But below 2500 and especially bad below 2000 rpm, it feels gutless. Has anyone else experienced this after degreeing cams?

The only other change I made was a fidanza aluminum flywheel. It seems that this change is also hurting me. In low rpm cruise/lug situations I get terrible harmonics throughout the car. It almost feels like a soft misfire. When combined with gutless performance in the cruise rpm range, it has me downshifting constantly. It's very annoying to drive right now. Just wondering if anyone else has experienced something similar.

Other items to note: the IMRCs were deleted long ago and I run a 4.10 rear gear with the car weighing only 3,050 lbs.

 

[SID297]

If you have the chance, before and after dyno sheets would be awesome.


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[me32]

Is it possible timing tables are not correct at low RPM?

 

[96GT226410]

I have a Fidanza flywheel and didn't notice any negative effects. Stock crank damper?

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[RJCarp2]

I have a Fidanza flywheel and didn't notice any negative effects. Stock crank damper?

Sent from my SM-N960U using the svtperformance.com mobile app

Thanks for the info. It's a Steeda under driver damper and I had the rotating assembly balanced with the new damper and flywheel.

With your fidanza flywheel, did you notice any additional vibrations during lugging situations or any "gear rattle" with clutch out in neutral. Both of these are pretty bad for me.

Also, regarding timing. It's the same table I was using before. It's a little conservative, but shouldn't cause all this.

 

[96GT226410]

Thanks for the info. It's a Steeda under driver damper and I had the rotating assembly balanced with the new damper and flywheel.

With your fidanza flywheel, did you notice any additional vibrations during lugging situations or any "gear rattle" with clutch out in neutral. Both of these are pretty bad for me.

Also, regarding timing. It's the same table I was using before. It's a little conservative, but shouldn't cause all this.

I did notice an increase in vibration, similar to clutch chatter. And gear rattle? I have noticed an increase in throwout bearing noise, or at least that's what I thought it was.

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[RJCarp2]

I did notice an increase in vibration, similar to clutch chatter. And gear rattle? I have noticed an increase in throwout bearing noise, or at least that's what I thought it was.

Sent from my SM-N960U using the svtperformance.com mobile app

Is your increased "clutch chatter" during clutch operation? All of my increased vibrations are in a gear with clutch out.

That TOB noise is actually gear rattle. What you're hearing are the constant mesh gears in the transmission bouncing back and forth between the drive and coast side of the gears at a frequency the same as the firing pulses of the motor. The aluminum flywheel doesn't have enough mass to keep the counter shaft gears on the drive side of the main shaft gears. I've read it's quite common with light flywheel swaps. A heavier trans oil will reduce the noise. If you want to test this theory you could change TOB tension or even unhook the cable, pull the TOB back so it's not spinning and start the car in neutral. Your rattle will still be there. Mine was.

 

[RJCarp2]

So there's not a single person on this forum with degreed cams these days?

 

[shurur]

So there's not a single person on this forum with degreed cams these days?

I know that I keep saying this...pm na svt (Todd Warren)

 

[RJCarp2]

I know that I keep saying this...pm na svt (Todd Warren)

I did. No response.

 

[me32]

Thanks for the info. It's a Steeda under driver damper and I had the rotating assembly balanced with the new damper and flywheel.

With your fidanza flywheel, did you notice any additional vibrations during lugging situations or any "gear rattle" with clutch out in neutral. Both of these are pretty bad for me.

Also, regarding timing. It's the same table I was using before. It's a little conservative, but shouldn't cause all this.

So you degreed the cams but did not have adjustments made to the timing tables after having the cams degreed?

I would log the car

 

[9397SVTs]

So there's not a single person on this forum with degreed cams these days?

I have '04 Mach 1 cams that were degree'd. The engine was put together 13 years ago, so I can't provide specs; I don't remember. However, the purpose was to shift the curve to the right.

Below 3k, it isn't a powerhouse. It is very driveable/streetable, though. I don't have an aluminum flywheel, as I believe a steel one aids driveability in the lower rpm.

I can relate to your situation. I simply accept that I am not driving a stump puller, but rather a high rpm, 32 valve, small displacement V-8.

I think a switch to 4.30 gears would help you. My set-up uses 3.55 gears, so I know about downshifting. It's a compromise.

 

[RJCarp2]

Well I figured it out. I hate publicly admitting this, but I like providing closure to threads because it may help somebody down the road.

I built this motor and degreed cams and somehow lost track of bank to bank timing. Therefore, I had both banks in time with each other. Or another way to put it is one bank was 180 degrees out. It was obvious when taking a step back and looking at Ford's install manual but undetectable on the degree wheel since the indicated crank degrees are the same. I fixed the cam timing last night. Now I need to put it all back together.

FYI - it will actually run in this configuration. I think only because we have a waste spark ignition which gives the off cylinders a chance to fire.

Luckily 180 out doesn't change piston to valve clearance. So, no harm there. I did a leak down test and it was perfect.

 

[shurur]

You are a valued contributor sir!!!

 

[52merc]

Thanks for admitting your mistake and letting us know what you found. I hate reading these threads and not getting the final solution.

 

[ZeroDCX]

Glad you caught this! Keep is informed.

 

[me32]

Keep us updated.