I have a bottom mount log manifold with a low boost (5lbs) turbo setup on a track car.
After a few laps the oil temperature is about 220F, coolant 180F, IAt maybe 100-120F but the car loses power on the straight.
The boost pressure will be fine, battery voltage is fine but the car runs incredibly rich.
I think the issue is VTEC failure IE it is stuck on the low cam because the engine doesn't have that VTEC noise also.


I can see the heat from the manifold has started to melt the shrouding on the VTEC solenoid, oil pressure sensor etc wires that come down from where the coils are but the wires look ok and the plastic clips etc are ok.

Has anyone with a turbo had issues with VTEC malfunctioning from the manifold heat?

I am thinking its either a solenoid issue, solenoid heat issue, wiring or a oil pressure issue causing VTEC to fail when the car gets hot.
I am running an AEM standalone and not seeing an oil pressure light so the sensor should be no issue.

 

AEM doesn't utilize that oil pressure sensor so it must be something else. Maybe the ems is pulling timing for some reason?

 

i looked thru all the correction tables and my tuner confirmed theres no anything that could cause the car to change so dramatically
I mean it goes super rich from 11's/12's to 10's and then 9's and it doesn't have that VTEC noise so I think its lugging on the low cam.

Question is why because for 1-2 laps it works ok, when it does it the car loses out down the straight but its still boosting and still very lively and running correct AFRS till about 7000rpm's, VTEC is set at 5900

 

If there's nothing at IAT / ECT vs Fuel Tables that seem abnormal, try looking under the 'Setup Tab' and look at VTEC parameters there. See if the tuner has set a max temp for VTEC.

 

Just opened my AEM Tuner, I was specifically referring to Tools-->Configure Outputs-->VTEC(usually HS1)

 

its a 1052u so I am using aem pro I couldn't find anything temperature based under outputs HS1 or VTEC, its set to work over -198F so work at any temp

 

I had the same problem on my old turbo s2000, it was the oilfilter relocation kit that was the problem. When the oil got hot the pressure dropped and the vtec did not work.

I had the revhard turbo kit.

 

kraft I have a relocation kit also that looks like it is from ebay so it maybe the same thing, did you manage to find a kit that worked and fix the problem?

 

You may want to up your VTEC crossover. Most log manifolds seem happiest in the 6500 rpm crossover range. It's worth exploring the set-point on a dyno. The optimum point will make the most power on either side of the transition.

Tim

 

99% sure is because of oil get hot and you lose pressure and vtec solenoid not work well