SPEN555

I have MY00, full s/s exhaust PPP and dawes set to give 17/18Psi.
In the car I have the following gauges; Oil Pressure, Boost and Oil Temperature. Also I have an A/F ratio meter and fuelling is fine at 9%+ CO.

With running higher boost will the Oil temperature gauge give me the warning to back off due to charge temperatures getting too high? Provided I keep an eye on the Oil temperature I cannot see it being a problem.

p.s. This is my first track day and so I can't see me ragging the ar$e off the car.

Damian.

john banks

See my thread about charge temps recently at Knockhill with the same setup. When really ragging it for 5-10 laps the charge temps went high at 17-18 PSI. I would set your boost to 16.5 PSI if you are not measuring charge temps. At this level at ambient 10 degrees the charge temps didn't go over 47 degrees C. I don't know how quickly oil temp would react, and I wonder if intake temps and EGTs would be more useful?

SPEN555

Cheers John,

I thought it would be you that replied to this one.

Yeah, I read your thread about the track results.

Are you able to tell me what are the effects of running the car too long at too high charge temperatures?

Damian.

john banks

Loss of power, less cold air, risk of det etc etc. Best kept below 50 degrees it seems. Turbo efficiency seems a bigger problem than the intercooler.

SPEN555

John,

If I put in Octane Booster for the track day that should help avoid det along with running Optimax and the fuel broquets I have in the fuel tank.

It's a 2.2 mile circuit and they are 20 minute sessions so by the time these effects would be starting to effect the car I think the session would be ending anyway.

Damian.

john banks

We were running SUL + OB to about 100RON and it did get over 50 C after about 5 laps of hard driving, and climbed about 1 degree per lap thereafter. Given a lap of Knockhill is about 65 seconds, then within 5 minutes at ambient 10 degrees C our temps were a little high at over 17 PSI. Track driving is so much more punishing than road driving it is unreal. Without monitoring the temps I don't think you can assume it is safe to stay out for 20 mins at high boost. Turn it down a bit and enjoy. OB may reduce the chance of det, but I gather that once the temps start to go up they really go up as the system decompensates. We backed off and did a few cool down laps. Caution advised. Bear in mind when using a Dawes that the ECU cannot reduce boost in response to knock. If things are getting hot you will only lose power by running too much boost. Also note that when really hot on the track the boost will go slightly higher than it does on the road, so I suggest you set for 16 on a road thrash first.

[Edited by john banks - 3/22/2002 2:21:19 PM]

SPEN555

John,

Cheers for your input. I will either turn back to 16Psi or just put the original piping back on.

Damian.

matt b

John
Been thinking about a dawes for a while now but as i lack a)any guages and b)mechanical knowledge have held off. took my car for a service and asked the guys to check the car out on their select monitor. with ppp and a falkland down-pipe the engineer said peak boost is/was 15.8. also asked him to check it wasnt running lean and so they popped it next door to the mot testing station. Result theyre saaid car was actually running rich (do have figure at home)
Garage thought 15.8 to be high but you Dawes boys are running about 17-18 arent you?
So if i was to get the dawes what performance difference would there be between 15.8 and 17psi (what is that in bar by the way).How noticeable a difference would it make.

-If professionally set up could you run the car safely in all weathers without the necessary guages. if not which guages would you need?

For the cost of the guages wouldn't an ebc possible be a better way to go as a way of ensuring proper worry free running.

cheers

Cosie Convert

MOT station would probably only check light load mixture. This is unrelated to WOT mixture ......beware !

john banks

There is a substantial difference between 15.8 and 18 PSI. I would expect a decat PPP to be running 16.5 PSI, but it can be difficult to get it spot on without a restrictor valve replacing the orifice. If you go over 17 it starts to fluctuate, but really to get the full benefit of PPP 15.8 is too low.

With PPP I think you could safely set it to run 17.5 in all weathers with either EBC or MBC.

You don't need a huge number of gauges - just air fuel ratio and boost, and I have not seen a hint of fuelling trouble running 18.5 PSI.

EBCs are not always the ultimate solution either, and there is no less need to monitor for safety no matter what method of boost control you employ.

matt b

Cheers for that guys. where have you mounted your guages then?

If i went the mbc route i'd ike someone with the necessary knowledge to set it up. Can anybody make any recommendations for either a helpful scoob-nut or a co in the N.london/herts area?

Oh yeah and where could i buy a mbc?

thanks