Overheating Track Car JZA65

[Nark]

Yup, I think you need to put some bonnet vents in. The air needs to escape and I don't think the RA6xs are designed very well for this purpose.

I've got the rear of my bonnet raised, but as JCMF said, I don't think it really makes much of a difference when you're driving. It's a high pressure area.

[JustCallMeOrlando]

Yeah, but you just did it to look fullsik Nark

[Nark]

Nah, that's what the Decepticons stickers are for.

I've always said that I'd put a piece of string at the back of the bonnet to see where the air is going, but me being the lazy arse that I am.... I've never done it.

[oldcorollas]

Nah, that's what the Decepticons stickers are for.

I've always said that I'd put a piece of string at the back of the bonnet to see where the air is going, but me being the lazy arse that I am.... I've never done it.

i'll chip in 10c for some string

[Matt-AE86]

If you want to be ghetto, but can make it look ok..

Get a grinder and grind as many 1 inch spread lines as you want, in any style, angle or whatever, just like some lines on a piece of paper, parallel with each other. Once you have done that, turn each 1 inch bit with some pliers and you will have a kind of vent, they work very well as well as the air runs over and under and out hahaha

I'm sure if Adsport saw this thread he could show you the real deal.

I recommend putting these between the engine and the radiator, near your pod filter, and in the back corner areas of the car, so the air can flow through and out.

The way they are I can only thing with driving and the air passing over the bonnet it will actually suck some of that hot air out.. Maybe face them at your windscreen for winter de-misting ?

[GA65CELICA]

All this is based off my 1G but i think they are basicly the same.
When you took the thermostat out and left the restricor in did you block of the return through the head. Where the foot of the thermostat would block off. if you havent then you might be circulating water around the head. This would cause the temp to slowly rise. I have just bashed/fitted a welch plug down the return passage. hope this helps.
Nice car by the way

[brett_celicacoupe]

i nearly thought about putting a fan in the space beside the starter motor. basically horizontal to the sump, just in that hole on the passenger side.

pulling hot air out of the engine bay will also help cool the engine itself while also removing the hot air thats floating around

[allencr]

Can you guesstimate the rad. output hose temp - the difference/drop between it and what your gauge says is going into the rad. ?
Within 10C(my guesstimate) of the inlet temp would need a bigger radiator or better air flow, nothing bypassing the radiator bulkhead, and the fan stuff is useless & an air flow restriction above 35Kph IMO.
Over 10C(my guesstimate) lower then the inlet temp needs more water flow.

[timottaway]

Thanks for all of you putting foward some killer ideas

as suggested in some posts i will planning to carry out the following...

- I will replacing the fan i have atm and opting for 2 12" slimline fans with a custom shroud

- installing a bonnet vent i have and installing a cold air induction system


- Running tests on intercooler, rad and oil cooler efficiency using 2 sensors before and after under race conditions, logging them and upgrade or reposition the respective cores or pump as needed.

- Monitor intake manifold temps and dyno tuning to ensure its not a tunning issue

Thanks again everyone, i will update as I run any tests and install/mod any components

regards

tim

[cultus]

A member here has a 1J manual in an MA, it overheats as well and we have changed fan, added another one before the radiator for push-pull setup, changed to soarer intercooler and mounted it to the side to allow more airflow to the radiator, run the hydraulic on high speed full time, raise the bonnet ... and she still overheats after flooring hard for like 2 minutes.

All failed and then another member said "the engine is too near the radiator" it's true coz the distance between the cam cover and the radiator is the diameter of the radiator hose which is sandwiched in beween. Then the owner had the engine and gearbox repositioned by 2 inches back and added the small fan underneath the top hose inlet without the outer "pushing fan" and the temperature was fine for hard driving, city jams ...

Another member's RA with 1J is still in the workshop, he knocked the firewall and try to have the engine as far back as possible ...

[timottaway]

Yeah No doubt the distance between my motor and radiator has something to do with it. It is probably creating a massive hot spot/s. Maybe I need to set up a some sensors to record under bonnet temps and maybe conduct this test on a drift car that doesn't overheat? When first carrying out the conversion the mission was to sit motor and gearbox as rearward and low as possible without having to do any serious firewall mod, ie. cutting, welding and adding sections. my motor and gearbox sit just shy of 3 inches more rearward than stock.

[cultus]

Hopefully with the scoop, the condition will improve.

The engine is very well positioned! Great job. My friend's is sitting higher. He is worried about overheating problem as well. Last resort he said : place the radiator outside the bar, use bonnet pin and cut out a portion of the metal bumper to accomodate the condenser and intercooler ...

[big wad]

we had a similar prob when running speedway years ago i was using a similar pump and no thermostat and the problem was the water was travelling to fast through the radiator and didn,t have time to cool it . we fitted a restrictor in the thermostat housing and changed to a pusher fan .problem solved. i hope yours is that easy. cheere bigwad

[Mr DOHC]

just for shits and giggles, change where the oil cooler is, , thats blocking an ass load of radiator, maybe mount it under the headlight, between the bumper and the rad support, then piss off the guard mould, so the air can flow straight thru and into the front tire well.

and another for poos and laughs, run it around with no bonnet for a few laps

[RiceburnaGTV]

Hey man if all else fails I still have one of the alloy radiators left that we made for the MX83 cressidas with 1j's in them, and I would definately look after you on price if you were happy to chuck a sticker Just Alloy Radiators sticker on your car Im pretty sure they are the same as the MA70 rads aswell?

Obviously go through the necessary motions first but let me know mate.

cheers
Nath