greatgonzer

iTrader: (3)

Here are my mods:

I currently have the following installed on my EVO 9: 2.3 stroker kit, FP HTA35r, AEM EMS, AMS Tubular Manifold, JIC Turbo Back With Test Pipe Exhaust, custom Upper Intercooler Pipe With Tial open dump wastegate, custom Lower Intercooler Pipe, Hallman Boost Controller, Walboro 255 Fuel Pump, HKS 272 Cams, ARP Head Studs, Exedy twin disk clutch, Custom 4inch Hard Pipe with k&n filter, 1000cc injectors.

Ok here is my situation, in Albuquerque, NM I was conservatively tuned to 510 on pump 91 octane at 23psi on a Dynojet. Not too shabby. I then had to drive all the way to Portland Oregon for business. While up here I was getting some surging and driveability issues and had to take it to a premier local Tuning shop.

They tuned my car but said that they could only get 425hp at 22psi 92octane and that is about as much as they could get out of it. They said that they highest that they've seen with my setup is about 460hp.

And post their tune my car makes a huge backfiring sound and feels like I hit a brick wall at about 6500rmp. I took it back to them and they said that they think I have a "trigger disk" issue where the AEM computer does not know what the RPM value is passed 6500K?! They showed me the log files where the RPM is at 6500K then suddenly spikes up to about 7400K? They do not know quite what to think of that and when my car hits that value it falls on its face and backfires. It did not do this before I took it to them.

So What hp numbers should I be expecting off of this setup approximately, and what PSI is the safest to run this on pump gas? Also can anyone explain to me how the AEM reads RPM off the motor?

The reason is that my tuner says that I should only expect about 460hp numbers and I'm thinking that is a bit low as my tuner in ALb said that I should easilly hit around 540hp on 91 octane with a decent tune. What do you guys think? Looking for input

nikkadanny

iTrader: (31)

go to a different tuner?

greatgonzer

iTrader: (3)

Yeah but when I already spent money in ALB on one tune, then some more money for the tune up in Portland, it makes more sense to stick with that tuner than to switch a third time. The cost alone is killing me. I'm just looking for info to take back to this tuner.

1: Does my situation sound like a "trigger disk" or whatever issue?
2: What HP values should I be expecting from my setup at sea level on a dynojet?

Thanks guys

nikkadanny

iTrader: (31)

im no expert on tuning but there are plenty of evos on here making more than that and running more boost. but 460 on 23psi is good

Conrad

iTrader: (3)

If your rpm is spiking in the logs it could be a crank sensor issue, becareful because if the ECU doesnt know what rpm the engine is actually at you can end up in the wrong load cell and tus end up with the ecu putting incorrect fuel and ignition in, subsequently this can kill the engine.

I'd get the crank sensor / cam sensor checked out and I have read that there are issues with the AEM ecu when one of these goes awol.

Good luck.

project_skyline

iTrader: (30)

Im not sure what would be causing your car to lose RPM signal but it sounds like it could possibly be a cam angle sensor, try replacing it.

Also why are you running that crap *** turboxs bov???

Evo_Jay

iTrader: (17)

I quoted "conrad" but this is to the OP:

Read david buschur's recent thread about this happening to him on his 900+HP car and blowing the head.

AEM cars have been experiencing this problem. Do a search on here.

David's thread is called "more broken parts for bad bish" or something similar.

scheides

iTrader: (10)

+1 on the cam sensor. If it was the crank angle sensor it'd basically be getting chewed up and jsut stop working; make sure the bolt on the end of your crank is tight (the one you can put a 1/2" drive into and turn the motor over with).

That said, 460whp dynojet with 'issues' seems dandy, and 500whp on pump @22psi seems dandy. Don't forget that not all pump gas is created equal, and you can lose some significant power by running cheapo and supposedly 'top tier' premium gasoline. Put some known good fuel in it, figure out your rpm issue and go back.

Magnumpsi

iTrader: (2)

Hola,

D you have to understand the differences here. The dyno in ABQ uses a really high correction factor. It is in the range of 1.18-1.25 depending on the day. Because of this all the numbers that come off of that dyno are high.

460hp is about what I would expect on a normal dyno jet reading with just a 1.0 CF.

As for RPM's I am not sure what to tell you. I would say if they think it is a cam sensor problem datalog "stat sync" and see if you loose it when the car backfires.

Let me know if you need anything Darrell I would be more than happy to get this sorted out for you.

Thanks,
Mitch M

R/TErnie

iTrader: (32)

Did you take it to John Reed in Portland?

BLKCarbonEVO

iTrader: (2)

I'll be the first to say ER love is where it should have went...

blk4doorawd

im having a similar problem. i have a 2.0 850r setup and made 625 on pump. then i noticed the car has been feeling slow took it to the track and my best mph was only 120 when i had previous mph's of 133 when i only had 520whp.

evoforlife

iTrader: (68)

check for a boost leak somewhere same thing happend to me, 6500 car would break up and backfire, ended up being a boost leak.

Evo_Jay

iTrader: (17)

+1

If your in the northwest, the only shop ya need to call is English Racing.....

greatgonzer

iTrader: (3)

Thanks guys for all the advice. Mitch (MagnumPSI), I really appreciated your tuning in Alb. But when I got up here in Portland my car was surging badly and was dying whenever I'd put the clutch in. We definately were not able to give the tune adequate time prior to making a 1200mile journey in the EVO. Not your fault under the circumstances.

So I had to find some tuners up here to help me get the surging and idle under control. The people I found here did a great job at that. Now If I can just figure out the 6500k + RPM issue. I will start with the CAM/Crank sensors and boost leaks. I may also just drive up to ER tomorrow and talk with Lucas.

And to answer

Kind of. John Reed is going over my map now with the current tuning shop. He also believes that it is a sensor. He thinks that the CAM sensor pickup may be flipped. I'll let you know what I find out.