hi all,
on a 95 wrx is there an output from the engine that changes volts with more revs? ive checked the injectors and the tach wire, but im just getting 12v ish, any help would be good, thanks,
phil.

 

Nope. Should be anywhere between 13.5 and 14.5 volts. 12v with engine running is to low. Sounds like an alternator issue.

 

so theres nothing at all that changes with the revs?

 

So what are you trying to do?????

 

The alternator may go up a volt from idle to 2000rpm. After that it should be stable. What is it your trying to acheive?

You will see voltage change on lamda and maf sensors. But there only 0 to 5volts.

 

my rad is in the boot and thinking of going electric pump that works off the revs some how, ill look at the alternator tomorrow, i was hoping to find a something that gives 2-5 volts on tickover and upto 13 volts when reved higher?

 

Your rad is in the boot! That's an interesting concept! May I ask why?
I think you'll find your alternator will go from 12.7 ish to maybe 14 volts from idle to full chat, I'm not sure you will find anything that has a big enough range of voltage.
Could you not fit 2 electric fans to the rad and fit a toggle switch in the dash? I built a bike engined mini a few years ago, engine in the boot rad in the front but the water pump wasn't man enough to push the water at idle. Worked for me!!

 

look at my avitar or go in my garage, i have a mk1 escort wit5h 95 wrx engine and running gear in, no room for rad in front, i have 2 fans but like your mini, the pump is not upto the job, just thought about an electric pump to help?

 

Ok, I found whilst driving it was up to the job but any more than 2-3 mins in traffic I'd be about to overheat, thats why I went electric fan and switch on the dash, only took a few weeks to get used to. Just flicked it on as I hit town or traffic. If I forgot the expansion bottle was attached to the roll cage behind the drivers seat, so I got a spray of steam on the back of my neck!! I only got one tho, f-ing hot that was, lesson well learnt!!
Just out of interest, if you can find a man enough pump, do you have sufficient air flow?
Gonna go look at you thread now, enjoy the build mate

 

There is no reason why the pump won't be up to the job, there are literally hundreds and maybe thousands of people who have put a Subaru engine in the back of there Volkswagen T25 van with the rad up front and engine in the back with no issues. My guess is you will have to redesign the cooling a little, maybe by using an external thermostat and junk the original one which really isn't suitable when increasing the volume of the coolant system so much.
HTH cheers Ian.

 

thanks, yes the air flow is very good now, it is a bit wierd as it coped untill i left it on the drive for a few weeks, now it doesnt seem to be doing anything, i have took the thermostat out, so that wont be an issue, ill have another look at a blockage today and i may just fit the electric pump ill let you know :-)

 

A friend of mine has a silimar project on the go, im not sure what rad he is using but it will be mounted in the front of the car..

 

quick update, i fitted the electric pump and made a few pipes straighterand it has solved it, i may put a termostat switch in the pipe work to turn the pump on and off, the only thing is, i cant tell if the pump stops working? but its all good for now :-)

 

hi again,
another quick update, just for them that maybe doing a project the same,
i tried just the normal water pump and it works fine now, so im guessing before i put the electric pump in, there must have been a big air blockage, thats why i thought it was broke, the electric pump is now used as a primming pump to make sure all the air is out :-)
as IANBOTT said the pump can cope with ease, i have removed the thermostst though as it has a long way to go,
a big thanks to all who had a say,
phil.

 

Hey Phil that's good news, but as said you really should be using a thermostat, I'm doing a similar thing with a vw beach buggy with the engine in the back and rad up front, due to this I've fitted an external thermostat from a BMW, works a treat and maintains a correct temperature in the engine.