Paulyy

After bending valves and getting the head freshened up. The engine felt less responsive bottom end but top end still felt good, better even. I noticed boost was coming on later also.

I got the chance to log it again.

This is my findings.

The first set of logs are after rebuild. on 98 ron. (us 93 mon)
The second logs are after head rebuild, same size valves ect just new. cnc cut valve seats.. nothings changed really. e85 105ron oct.

My limiters have changed going from 98 to e85. that's why the shorter log.

I'm thinking going back to 98 and see if any difference. might be non consistent fuel blend.

refresh951

I am not sure how much you are going to be able to compare here Paul. These curves are calculated rather than dyno curves? If so, the boost curve depends on the load rate and getting that consistent enough without a dyno is going to be difficult.

Paulyy

If this helps. Same road. Same gear (3rd)

these logs show exactly what i'm feeling. despite numbers. The curves are telling the truth.

The only curve calculated is the "torque" but the way the car feels.. is accurately shown in the curves.

I can actually feel the extra lag and the less responsiveness in the car bottom end, which shows in the curves.

In another post i had an issue with different fuels. and the 2 curves represented what i felt. changed fuels and logged it, got the same curve as i originally had.

This is why i like data logging. i can actually compare logs because 3rd gear load won't change if done on the same road.

Tom M'Guinn

Any chance the boost controller needs to be tweaked for the fuel and associated spool up differences? That kink in the curve looks like my boost controller when it ramps up too fast, spikes, and over compensates until finding its target...

Or a leak somewhere -- intake or exhaust...

refresh951

Is one plot pump and another E85?

333pg333

Not sure if this would cover off what's happening but is it possible that you have skipped or moved a tooth on the cam timing? That might explain why bottom end has dropped off but top feels even better.

Paulyy

What i did notice though. My 18 psi setting is now ~16 psi so i had to increase the setpoint value up from 49 to 53.
The gate pressure value (which holds the gate shut) hasn't been touched and is set onto 11 psi.
The spike in the graph has nothing to do with the boost, looking at the boost curve. It only fluctuated 1 psi.

No exhaust leak. Will check intake, but i don't think theres one.

correct. I have an e85 plot somewhere which is identical to the 98 one.

Worth a check again but IICR checking that a few times before starting.

User 52121

Exactly what I was thinking. Cam timing.

Paulyy

Just in the middle of checking cam timing. It's dead on..
The flywheel marking is dead on the pointer and the cam is dead on with the markings.

Should i move it back a tooth and see what happens?

Paulyy

For good measure, i took the cam belt off aligned it all again and went for a drive. same..

I want to check the cam key for any sort of damage for any reason. didn't have the tool at home so will do tomorrow.

Paulyy

Hmm. Pulled apart all the intake side. put it back together. No change. Also doubled up on intake gaskets..

Paulyy

when i run out of e85, going to put in pump 98 again. just to eliminate if the fuel is causing issues.