Running lean...maybe

[Jake]

Hi Guys,
          I\'m wondering if someone can help as I need some advice.  A while back I had a service at WGT and they put the car on their new dyno.  The run was stopped as they said it was running lean on the top end after 5,000rpm.  They measured the A/F ratio to be about 13.5 to 1 I think.  Pip seemed to suspect that the injectors needed cleaning so I have it booked in on the 6th October for that.  Mechanically the car is standard apart from an RE Amemiya filter and a cat back.  It\'s a \'96 RS.

Problem is I\'ve just been to TSL Motorsport in my village to talk to them about getting a laser alignment done.  I was chatting about the car with Graham and I told him that it was running lean on the top end.  He asked how I know that and I told him what happened at WGT.  He said it was very difficult to generate proper load and to get proper cooling to the engine on a dyno so you couldn\'t really say that.  He said that a road run would give a much more accurate figure.

I\'m now a little confused.  I know that TSL have a lot of experience with setting up ECU\'s on Subarus and Evo\'s using rolling and road runs so I\'m sure they know what they are talking about.  Plus WGT have been tuning FD\'s for ages and are very well respected although I know they haven\'t had their dyno that long.  I\'m now not sure what to do.  Could I be wasting my money getting the injectors cleaned when there might not be an issue?  What are others peoples experiences with getting accurate A/F readings on dynos?  Thanks

Jake

[TRex]

My Advise.
 1. TSL did not have your car on a dyno doing runs and tests... they are in no position to say your car may not be lean or not!

 2. \'FACT\' - Pip Gardner is the most experienced bloke in the country with regard to Rotary tunning and set up.  TSL prolly would not know a rotary if it hit them!
 Who would you trust....  

[John Yorke]

Jake

Best advice is go with Pip the man has dealt with rotaries for decades, no dissrespect to TSL but these cars need to have 10.5 - 11.5 afr to be cast iron safe and that is with it being tuned on the rollers.
I think most people go for tuning on the rollers to be safe - you are much more in controll than when driving up the road at insane speeds trying to get your map right, true you do not replicate actual driving but it is as close as we need to be.
The other thing to remember is you normaly only have to have one case of det to destroy your engine it is the main difference between a boinger and a rotary.

[clive]

Hi Jake,

Pip has been around these cars long enough for you to have faith in what he is saying, ask him for the reason he came to this conclusion and l am sure he will explain it to you.

As for your other question, Yes he is right, many many good tuners will tell you that for optimum tuning you need natural air being passed over the car  in real life conditions with a Dyno or Rolling road only being a tool for getting your engine running somewhere "near right"

What bears this out is that F1 and Top Drag teams virtually tune their cars from their own weather stations on the day taking into account ambient temperature etc.

[BlitzBoy]

If you ran 13.5 afr on the rollers, imagine when you get more AIR on the road the intake charge will be even more denser hence you will ran even more lean on the road. Pip is right to abort you dyno run, seems you do have a problem with your injectors or fuel pump

[Jake]

Thanks for the advice guys.  When I had the service Pip said the reason he suspected the injectors was that when he changed the fuel filter it was filthy and full of all kinds of cr@p.  He suspects that some of this has migrated it\'s way through the fuel system and is clogging the injectors which makes good sense.  I was just a little thrown by what I was told at TSL, thanks for the second opinion.

I can\'t wait to get it sorted and running right as I\'ve pretty much been babying it since I had it as Pip said I shouldn\'t go above 5,000rpm.  It will be great to get it in good working order.  Plus with it running lean Pip reckons it\'s giving away a good chunk of bhp, especially on the top end.  It\'ll be great to really drive it up the revs again and not just being on the primary turbo all the time.  Can\'t wait :yes  :yes  :yes

[J.j.]

I\'ve pretty much been babying it since I had it as Pip said I shouldn\'t go above 5,000rpm.

This must really hurt !!!!    :evillaugh

[Jake]

haha, tell me about it.  Probably made worse by the fact that I\'m used to driving an Integra Type-R before I got the Rex.  I\'m so used to working the gear box like crazy to stay above 6,000rpm...this is killing me...

[Jake]

Hi Guys,
          Just thought I\'d give you an update to this problem.  I went back to WGT last Thursday to have my injectors cleaned to hopefully sort out the running lean problem.  Got up early so we could get there about 9:30 as it\'s a 2 hour drive.  Car was driving great on the way down.  Plus I\'ve just had a laser alignment done and two new Toyo T1-R\'s on the front :3gears-rh

The car went in as soon as we got there, top of the engine off and the injectors out for a cleaning.  Pip said that they actually wern\'t too bad, they improved about 5-6% with the cleaning.  The car was then put on the Dyno to check if this had done the trick, only problem is now the first turbo is barely boosting at all and the second turbo is missing in action. :reallymad

Pip reckons it could be the solenoid pack so the tops off the engine and the solenoid pack is changed.  Back on the Dyno but it\'s still the same.  By this point it\'s the end of the day so nothing more can be done.  I then have to drive home in the most hideous RX7.  The boost is so random.  Sometimes I floor it and you have a 3 second pause and then boost comes in.  Sometimes you floor it and it\'ll boost a little and then it lets out like a yelp when you come off the throttle.  Even when it\'s boosting it sounds like its leaking.  I was in 5th once at about 3,500rpm and I floored it.  Nothing happend, I spent about 30 seconds at WOT and only increased about 5mph, I couldn\'t believe it. :confused:  :confused:  :confused:

I\'m so hacked off.  I went down for my injectors to be cleaned and came away with a big turbo problem that I didn\'t have in the first place.  Pip says I\'ll have to go back down to get it sorted but I don\'t really feel like taking any more holiday to get this problem sorted.  It sounds to me like something has either not been put back right or has been broken when the injectors came out?  Does anyone have any idea as to what might have happened?  I wouldn\'t be surprised if it was something simple and I don\'t want to take another day off work and pay someone to fix something that might be simple.  Any ideas?  Cheers

Jake

[J.j.]

U bought the car from newera right??
If so, at least it can be fixed under warranty.  

[Jake]

Yeah I got it from Newera.  Their cars don\'t come with a warranty which I knew before I bought.  I\'m going to have to speak to WGT, it was running a little lean but the turbo problem I feel has been introduced so I\'ll have to see what they say.

[iaint]

One of the problems with the turbo control system on the rex is it doesn\'t age very well.  Just look at the number of posts about boost issues.  Unfortunately it\'s likely that something was disturbed in the control system to get at the injectors and it\'s not failed - favourites are cracked solenoids, leaky vaccuum hoses or dead pill valves.  Not really WGT\'s fault as it\'s more a feature of the age and state of those parts.

On the other hand I wouldn\'t be very impressed in having a knackered car to come home in even if it wasn\'t their fault.  In your position (or anyone sufferning random boost issues) I\'d be very temptyed to have all the hoses and actuators/solenoids and gubbins replaced as replacing the bit that failed might work now but the rest is likely to be in a state too.

I had all my vacuum hoses and solenoids replaced when it was rebuilt and have had no problems since then (2 years) - before that I never knew if I would get boost or not!

Iain

[stu0x]

When did you get your car? I got mine from Newera in April, and I got a 12 month warranty with it (which covers rotor tips)

[gsb876]

As a few people have said Pip is the man for rotaries,

Stick with it and get it done, i always take my car there and have never had any problems.

[John Yorke]

Jake - the thing is this is an OLD car, bits wear out, sorry to hear your problems but I would be very supprised if it was a problem caused by Pip\'s fetling, best advice is go for a full hose job and sort the problem once and for all as per Iain\'s post.
HTH