Where'd my power go?

Hi folks,

I come before you today.... a broken man.

I got took my car into APC Racing today (in Springwood for the QLD folk) and got it tuned as part of a service and AYC flush.

Sadly it only pulled 129kw at the wheels

It's completely stock and apparently has only done 37,000kms (I'm beginning to doubt this...)



Where do you think all my power has gone? I was hoping for 145-150 based on a 30% drivetrain loss.

Apparently the AFR's were a little bit rich but nothing outrageous. Compression tests where all good. New plugs fitted today.

Maybe I'm leaking boost?

Lee

 

boost leak? low octane fuel?
how many psi you boosting?

 

Fuel has been 98 for several tanks since I got it.
Don't have a boost gauge so not sure about the boost - might see if I can get one this weekend.

That's all I can think it is. Is there any way to check the factory BOV for leaks?

cheers

Lee

 

Prolly a mix of the fuel and car age. A normal car will lose power as it gets older and parts wear.

 

The dyno guy should of hooked into the boost line so you could see what it was running. Check for leaks in the piping.

 

I would suggest resetting the ecu. Do you have the stock intake setup?

You do need to find out what boost it was running as well as the AFR's!

Most stock cars do around 150kw.

 

I've reset the ECU a couple of times since I've had it and the intake setup is stock.

I'll give them a call back tomorrow and ask if they recorded the AFR's and the boost levels.

cheers

Lee

 

If you don't mind me asking, what's making you doubt the km's?

 

I'm not sure exactly the interior is in good shape, the engine bay is clean and tidy, no under body rust.

The main thing is that the workshop thought that the noise I'd been hearing from the rear might be a worn wheel bearing - how many km's do wheel bearings last for? ...and the AYC fluid was pretty brown (but it probably would be after 37,000kms??).

I'm just wondering if the lack of power could be due to a worn engine as takumi mentioned.

cheers

Lee

 

Sounds like mine.. At first glance everything looks mint, but after a while little things start to catch your eye. I have a little bit of wear on the steering wheel which is usually a deadset giveaway on true kilometres. No strange noises yet thankfully.

The service records do seem to reflect the low km's though..

 

Thats No good Lee, it will be interesting to find out the cause. Just out of interest, how much did the service cost at APC?

 

Don't ask my other half might be reading...

I'm not sure what a service costs on it's own - I think for what I got which is a "major performance service" (which includes a dyno run and tuning if you had an aftermarket ECU) it's about 400-500.

I got them to put Greddy iridium plugs in it at $28 a pop so that blew it out $650 *gulp*

I think I'll try Neal Lowe next time - APC were ok but seemed pretty keen to sell me lots of expensive brand name stuff and the quotes I got for an exhaust were very different from what Christian was told on another occasion.

cheers

Lee

 

Hi Lee, if you need to borrow a boost guage just let me know. I am in Brisbane, happy to help out if I can. I am going down the wheel bearing path myself so might be able to assist you with that also.

 

Yea how'd you go with that, Graeme?

 

could also be a faulty wastegate/actuator.

 

Mmm... 175bhp ATW for a Manual car isn't great. That's what we see for completely stock Autos in the UK.

That torque curve looks a bit flat - again, suggesting a boost leak, but without knowing the gear the run was in, etc it's difficult to say as one can't calculate the flywheel value to see if it's miles out or not.

 

Hi Keiran,

the run was done in 4th (according to the detail at the bottom of the graph). I rang them back today and asked for another graph with boost and AFRs on it.

He said boost peaked at 9.8psi, will be interesting to see if it drops off suddenly at high rpms.

cheers

Lee

 

9.8 is reasonable, if it stays above 7psi for most of the run, then boost isn't the problem.

 

Lee, how does the car feel? Have you driven another Legnum or Galant to compare?

A dyno is nothing more than a tuning tool, the outputs will vary at each dyno. A little fiddle with a couple of numbers on the computer and it is easy for your car to look like it is making more or less power. Call me cynical, but the aim of a performance shop is to sell parts to enhance performance.

I have a boost guage in my garage that I am happy to let you use and a galant to compare with if you like.

 

Hi Graeme,

I've driven a tiptronic and my car feels quicker than that did.

I hear what you're saying about performance shops

Thanks for the offer of the boost gauge I'll send you a PM and try to arrange something.

cheers

Lee