SoNiCa

This is the question I'm asking to myself in some periods. I'm afraid of doing long distance top speed runs because of the durability issues. In the past, when I was driving a N/A car I had never think about the durability issues. WOT and GO!

But now I have feeling like that. And whenever I want to do a long top speed runs over 1000 question marks appears on my head. Big end failures, fuel pump, oil pump, oil heat, fuel rails, high egts etc..

Basically, I want to go an A place to B place at the avarage speed of let say 140 mph. In general I'm not big fan of top speed runs but I just want to be able to do top speed runs without wondering any durability issues.

I want to know if you guys who had modified their cars have the same feeling or not?

I think I'm gonna try this in the near future of course in the safe driving limits and in a cold weather. I cant live with this fear =) I have spent my time and money on this car and it should be able to pass this long speed run.

Here is my mods so far. If your car able to run top speeds without problems please tell me the specs

Stock engine (86.000 miles)

Apexi PowerFC Ecu
850cc Injectors
Super16G turbo
STI8 Intercooler/Splitter/WaterSpray/STI8 Scoop/Undertray
Walbro Fuel pump
K&N RU-3130 Custom CAI
AVO Turbo Inlet Hose
3" Blitz Nur Spec R
3" Invidia Downpipe
GTspec headers/Uppipe(wrapped)
NGK PFR7B plugs
2xEGT probes(cyl#3#1)
Defis, wideband etc..
15W50 mobil 1

harvey

iTrader: (48)

Prolonged WOT kills Scoob engines, especially non standard Scoob engines but the same will be true for other highly stressed turbo engines.
I think the essential guages for high speed running are EGT, oil temp and pressure and charge temperature. A knock link is also useful.
With the above, you have the chance of avoiding a disaster.

dowser

You could get it mapped so that it will survive extended high speed runs. I used to do that with early new age STi's in Switzerland. Cars produced between 310-330 hp but ran stock boost above 6k rpm (leaned out fueling and advanced timing....but mainly achievable because of freer flowing exhaust that we fitted). This probably cost 20-40hp as opposed to mapping for max power with shorter WOT runs......but my customers lived very close the German autobahns

For myself I simply avoid WOT for more than 60 seconds - accepting that those last 5mph are not really important, you can reduce throttle opening to stop turbo from trying to kill everything downstream from compressor and remove all the strain from the engine

Richard

silent running

It's not just you that's paranoid. I have exactly the same fear - my old Clio 16v loved to be revved, it would sit at 6500-7000 rpm all day long and you never felt that it would ever give up. You could cruise on the autobahn continuously at 130mph without a care in the world. Much as I love the sound of my Scoob, it does sound fragile, like you don't want to run it at high speed for too long which is a real shame. Plus the bonnet starts juddering around, it starts whistling etc etc. It's just not a confidence inspiring car at high speed.

Trap2Terrorist

iTrader: (3)

I've got a WRX that's been slightly modified (ecutek remap, Walbro fuel pump, HKS panel filter, H&S bb).

I recently ran, foot to the floor, for 4 to 5 miles. I was at 142mph (german road) for that time and it did make me paranoid about the stress on the engine.

No ill effects though.

theotherphil

I have had my MY95 UK Saloon off the clock for approx 6 miles playing with a SL55 AMG on a continental road. All bolt on mods, running in excess of 300bhp.

Chad!

Hmm....I now think this. Never used to. I did a high speed run, me in my standard UK turbo (1999), running 16/17 PSI boost. Against a V8 4.4 litre BMW. The private road was about 8-10 miles long. This seemed to be ok, though the oil temp went very very high. About 125 degrees. Which is far too hot in my oppinion. As I said, this seemed to be ok at the time, until the next day. After a small amount of spirited driving, the turbo died. Not completely mind. The internal seals gave up. So I had water and oil coming out of the exhaust. Now with it's new (second hand) turbo, it's fine. So I would say that the turbo is the weakest point if running higher than standard boost.

silent running

Yes I think the problem is that in most other cars, if it's supposed to do 140 or whatever, I'll happily wind it up to that speed or as near as poss, and it doesn't feel like a problem - no weird noises, oil and coolant temps fine, everything OK. Yet in my Scoob, it's like I'm attempting the land speed record in a bloody jet car or something. Maybe the Japs were right to have a 110mph limiter. Maybe the aerodynamics of the Scoob just aren't up to high speed running. Should have got an an M5 Touring instead of a WRX wagon...

X SOOOBY

i have had 2 engine failures doing high speed runs 1 piston the other big ends both with mapping from a reputable mapper or so i was told i have not got that opinion now the engines as have been said a million times b4 are designed for squirts betwean bends not prolonged high speed runs

needless to say i know what my scoob can do top end so there is no need for me to do another

bladeboy2041

Did a high speed run the other night on an unlit motorway section in the North West. Got up to about 140 with quite a bit to spare. Noisy, but other than that no problems from an engine point of view.

However, there was a loud bang and then a rubbing noise from the front nearside wheel. Closer inspection revealed that part of the plastic trim that runs from the wheel arch to under the front grill/bumper had come away and peeled itself back. The front tyre had worn a rough hole in it and it's now secured with tie-wraps!

Engine very impressive though. Pulled hard at the ton in top gear and just kept on going. Reckon I might see 160mph but wouldn't hold it there for long though.

MY02 JDM spec stiV7. Milltek exhaust, remap and induction kit. Dynoed at 341 bhp.

Fuzz

As long as you have the right gauges then it's all down to knowing when to take your foot off. I know mine will do a gps recorded 174mph and it's tuned to the limit of the standard Uk bottom end.
One day I will eat my words but two years on I'm still waiting for the big bang to happen.


Andy

bladeboy2041

Andy

Not maxed mine out yet but with the abovementioned spec should mine do a genuine 160mph? Bhp is 340.

cong

ive done a 149 uncalibrated on test track with 273bhp RR. sure i could have gone faster, ive done this quite a few time on my m99 uk turbo with 81000 on the clock, was more afraid of the bonnet flying off then the engine going bang lol

Fuzz

You tell me. I've got a classic shaped one with a 6 speed, 415bhp, a front mount and plenty of gauges, so a little different to yours.


Andy

bladeboy2041

Just a bit different yeah!

Had mine tuned at Powerstation and with the tune on offer 340 bhp was about the limit. Their dyno room is impressive!!

Next step was a few grand more and front mounted intercooler. Might upgrade the suspension next.

The bonnet does seem a little agitated at serious speeds though.

Perhaps 155 - 160 mph is the max. Must test it when I get another unlit section with no cars on it. Only way to do it safely.

bladeboy2041

PS: Anyone got any ideas as to where I can get a replacement front nearside wheelarch-plastic-protection-shroud since mine has bitten the dust?

Cheers

Mike

Fuzz

I know, it might have been me that did it.


Andy

bladeboy2041

Nice job Sir! The thing flies.

Quick question. Are the JDM engines quite tough? Relatively speaking of course.

Mike

Fuzz

Have yet to see a JDM blow up like the chocolate classics do.
So far, so good.

Andy

alanbell

iTrader: (6)

My best high speed is 163 mph , in one mile at Elvington ,

SoNiCa

The thing is not the max speed you see on the clock. I have 1 minute runs at 160 mph when the car was stock. I'm talking about how far you can go at these speeds.

You may remember the Saab tests at Talladega track. Saab also produces turbocharged engines and they can stand the prolonged WOTs.

24 hour at 140 mph:
http://home.swipnet.se/danny/talladega900.htm


I had also Clio 16v in the past and the thing only happens is the low performance after prolonged top speed runs.

Shark Man

If I even considered excessively long WOT runs for any duaation running higher than stock BHP.

I would want to see fitted:

an Air-to-Air oil coooler (thermostatically controlled).
A lower temperature coolant thermostat
Huge intercooler (preferably FMIC)

A CONSERVATIVE ECU map - sod this mapping for 98 or 99 RON. What is safe is dar more important than what gives the most BHP with minimal ignition retard.

silent running

Yes forgot to mention that I also fitted a front mounted oil cooler on the old 'Valver' and of course as standard Renault had the common sense to fit valvers and ****** with oil level, oil temp and oil pressure gauges as well as the rest of the clocks.

blueyzfr1

I have a JDM Classic so what about them????