Questions about VW1302RSis ride

[VW1302RSi]

Originally Posted by Steve C

Hi Scot

Well done, you just inspired me to drop the paint brush and go out into the garage, my wife will call you later.

To the casual observer your car still sounds like a bug, altough one with a few herbs added.

Steve

Hey Steve

Thanks for the comments about the car, I haven’t heard from your wife yet? You must have picked up that paintbrush again?

Took the car to the track on Friday, I’m still smiling best fun I’ve had with my pants on for quite some time.

I have posted it at http://vw1302rsi.multiply.com/

Good luck with the painting

Scott

[Steve C]

Hi

Got back into the painting before she noticed. Im trying to keep ahead of the builders and carpet layers. Almost done and then I can get back to the bugs.

My ADSL comes and goes, I will download the video whens its working and have a look.

Steve

[jakriz]

Hi Scott,
Good to see another sooby superbug conversion.
I've had mine on the road since late 2004, it's a daily driver & it's done 9 supersprints with the local porsche club in that time as well.
I was wondering how u are going with your inlet temps. I'm running a RS Liberty water to air intercooler on my wrx engine. My inlet temps run around 5 - 10 degrees above ambient on the street, on the track I can get them up to 50d which I have been told by many Subaru experts is more than acceptable & I shouldn't worry until I get near 70d inlet temps.

Also how are your water temps going as well, I noticed that your inlet & outlets run incredibly close to your sump & exhaust headers. The temps between those are huge.

I also read about your mod to your thermostate to help bleeding, I actually don't run a thermostate, 2 reasons, 1, it gives the perfect bleed & doesn't allow air pockets around number 4 piston water jacket & 2, I have 16 litres of coolant cooling my engine (standard wrx is 6 litres) I spoke to many guys that had done kombi conversions, some of which had experienced head cracking & warping due to the thermostate opening once warm & letting a huge volume of cold water in to the engine. I just let mine warm up each morning properly & it's been sweet. Just something u may want to think about.

regards
Jak
http://www.superbeetlesonly.com/foru...y&cmd=sc&cat=6

[ricola]

At the risk of hijacking..

Jak: in the UK there is a BIG problem with those surges of cold water straight to heads on the Rover K series engines when used in mid mounted cars (MGF/Elise) as they too have the thermostat on the inlet. When I built my libra I fitted an external BMW thermostat on the outlet and removed the original one and it worked fine. I won't consider removing the thermostat as 90% of engine wear is on warm up, maybe an external mount is a good option for you? I'm thinking about it for the cabrio..

Rich

[jakriz]

Hi Rich,
I agree totally about the 90% wear at warm up, but I think that comes down to how u treat it as well. I'm quite padantic with my car as it's my only transport, so diligency about warm up procedure each morning has become a mindset. I don't take it over 3000rpm until my water temp is at least 70d & NEVER get it on even the smallest amount of boost until my oil temp is up as well. For the first 20minutes each morning I'm in traffic getting nice & warm as I drop the kids to school so I''m lucky that I'm not going straight onto the Freeway.
Since December 2004 I've done 28'300klms in all weather conditions so I'm now familiar with what water temps , oil temps , oil pressure & inlet temps are/should be. Hey , I could be way off, but I got quite a bit of feedback from a vast array of Subaru engine builders & tuners in regards to my application.
hopefully it will keep running as superbly as it has been.
I will say this though, since taking out my 2275cc vw motor & putting in a wrx engine, I very rarely spend anytime in the garage anymore, almost to the point that I'm bored & looking for things to do to the car!
regards
Jak

[VW1302RSi]

Hello Jak,

Thanks for the reply

Originally Posted by jakriz

I was wondering how u are going with your inlet temps. I'm running a RS Liberty water to air intercooler on my wrx engine. My inlet temps run around 5 - 10 degrees above ambient on the street, on the track I can get them up to 50d which I have been told by many Subaru experts is more than acceptable & I shouldn't worry until I get near 70d inlet temps.

My cars is powered by a 2.52L N/A engine so inlet temps are one of the things I don't have to worry about.

Originally Posted by jakriz

Also how are your water temps going as well, I noticed that your inlet & outlets run incredibly close to your sump & exhaust headers. The temps between those are huge.

Your right the temp difference between the exhaust and the coolant pipes is huge. Only the thermostat to rad pipe/hose the runs near the exhaust and I don't see over 85 degC normally on the gauge and when I dynoed it she was just peeking of 90 degC after two hours.
The other thing to remember is lots and I mean lots of vehicle manufactures run coolant pipes near exhaust systems, Its not a problem on my car if it was turboed it may be a different story.

Originally Posted by jakriz

I also read about your mod to your thermostat to help bleeding, I actually don't run a thermostat, 2 reasons, 1, it gives the perfect bleed & doesn't allow air pockets around number 4 piston water jacket & 2, I have 16 litres of coolant cooling my engine (standard wrx is 6 litres) I spoke to many guys that had done kombi conversions, some of which had experienced head cracking & warping due to the thermostat opening once warm & letting a huge volume of cold water in to the engine. I just let mine warm up each morning properly & it's been sweet. Just something u may want to think about.

The reason these guys cracked blocks or heads or what ever was due to thermal shock and as they have worked out if you open a thermostat when one side is 30-40 degC hotter than the other side thermal shock can occur and its worse when you run huge coolant volumes.
When you look at my car running from cold as the engine warms up coolant still circulates through the complete cooling system and as the engine warms up to operating temp and the thermostat opens the gauge drops about 5-7 degC I have confirmed this with a temp gun on the coolant pipes, so there is no thermal shock.

Most manufactures have a small hole in the t/stat one of its tasks is to allow the coolant to circulate before the t/stat opens and warm up the cooling system evenly, all I have done is enlarged the hole due to the amount of coolant I’m running.

Again look at big trucks and coaches some of them have over 15L of coolant in the radiator alone and they run thermostats and warm up evenly, why because the circulate enough water thought the radiator etc to allow an even warm up before the thermostat opens.

What sort of temp variances do you get on your gauge between say:
1- Crawling along in rush hour?
2- On the race track?
3- A fast drive on the motorway on a cool night?
I’d love to know.


Not trying to be rude or a know it all but I still can’t figure out the logic in not running a thermostat on a road car.



Just something you may want to think about
Scott

[jakriz]

Hi Scott,
Sorry, I just pressumed u had a turbo version.
My water temps are excellent, well I think they are. In traffic, regardless of summer or winter the highest I've seen is 86d, then if I turn my thermo fans on I can drop it 10d in about 5 minutes. I was told that a thermo fan on both sides of my radiator , one pushing air, one sucking air wouldn't work as the fans would work negatively against each other. Not true.
Fast driving on the Freeway which is everytime I drive to the track as I have to leave before the sun comes up it just sits on 80d without the fans on, in summer it sits on about 84d sitting on about 80mph.
On the track, which was one of my biggest concerns about the conversion my water tamp won't go over 90d with the fans on & my oil temp has only got as far as 85d with no external oil cooler & thats in 35d Aussie summer heat, 5 x 2 minute laps at a time on boost the whole time. Oil pressure is 80psi plus all year round. I also have 2 radiators for the intercooler, one 300 x 300mm one next to the gearbox, the other a 600 x 300mm alloy one sitting in front of the radiator with it's own 9 inch thermo fan & water spray for the track to lower inlet temps.
I was given the advice not to use a thermostate by someone who does conversions for a living but I also checked with my engine builder as well before doing so. My 2 mates that did their conversions at the same time are also not running thermostates either with no ill effects. It seems to make sense to me, but then alot of weird stuff does
I'm just about to crack 30,000klms with my conversion & i've driven it through snow, flogged it on the track in summer & winter & also driven it though 30cm of flood water, whilst still taking the kids to school in the morning & getting close to 38mpg. It's working a treat.
On another note, I also use 15/40 weight oil on the street & 20/50 on the track, contrary to popular beleif suby engines don't like thin oil, especially for the track, thats how they do big end bearings which is quite common.

Have u had your car on the dyno yet Scott, would be interesting to see what the twin cam 2.5 puts out at the wheels.

regards
Jak

[VW1302RSi]

Hi Jak

Originally Posted by jakriz

I was given the advice not to use a thermostate by someone who does conversions for a living but I also checked with my engine builder as well before doing so. My 2 mates that did their conversions at the same time are also not running thermostates either with no ill effects. It seems to make sense to me, but then alot of weird stuff does

With out trying to sound like a know it all prick I hope you didn't pay for that advise.

But seeing as I don't know everything (as my wife points out) I decided to ask a few professionals,
So I called a service manager of a Toyota dealership I know who is an A grade mechanic with over 40 years in the trade and playing with race cars, and he agreed with me but gave me some grief for asking him a question I knew the answer for. But as we both could be wrong I wanted to confirm so I wanted to asked a 3rd party. So I left the warmth of my office and went down to the workshop and asked some of the qualified mechanics there what they thought and they agreed with me, but I thought they would.

We just can’t see any reason why you wouldn’t run a thermostat, unless it was to overcome some other problem?

Originally Posted by jakriz

Have u had your car on the dyno yet Scott, would be interesting to see what the twin cam 2.5 puts out at the wheels.

Yes I have had my car on the dyno it’s a EJ25 SOHC not a DOHC and as I don’t like talking about power figures as it always end up sounding like fishing story’s, and it depends on the dyno and the correction methods used, sae, din, temp correction bla bla bla.
It has enough for the moment.


Scott

[jakriz]

Like I said Scott, 30'000k on the conversion, driven daily & flogged on the track with Porsches. if it aint broken, don't fix it.
Each to their own.
Just can't understand why u would ask your local toyota dealership advice about a wrx engine in the back of a 71 beetle?
Good luck with yours.
regards
Jak