So I'm look to the vast wealth of knowledge to help me as old carb engines are not my specialty!

When on track all is fine until oil temp rises above 105 ish, from then on the engine struggles and will not rev out past 6-7k it just sputters and spits with no power. Once cooled again its ok for a while until oil temps rise again. Water temp is steady and I had it tuned at Daytuner the beginning of the year but once on track and not the road its not great.

Can any one explain what is really going on, all I can think is the fuel in the float bowls might be flashing off and not allowing enough to be drawn into the cylinders but that's just a guess, there's obviously an air/fuel problem occuring.

I think I will just have to fit an oil cooler and hope that sorts the problem unles anyone has some pearls of wisdom because its beyond my experience.

Cheers

Oil cooler and some form of cold air feed. Check the Rad is working correctly (fan is the right way round) and try looking at some vents on the rear of the bonnet to let the hot air out.

Thanks Jeff, I've cut some bigger holes at the back. I tried the cold air feed which overpressurised the engine bay and affect air flow through the radiator and caused watrr temps to go up.

I think oil cooler is the only solution.

As you have a screen on your car depending on where the vents are you might be trying to vent out in to a high pressure area. You can make a minomitor with some clear tube, water and food colouring to see how the vent in the bonnet is performing. I was surprised by how much I learnt doing this on my car.

The vents are on the side as I have a manometer and looked into the pressure regions. I might try a cold air feed and remove the floor to allow the air to escape and see what happens.

I meant cold air feed to the intake....

Oil cooler will help, try and open some holes above the exhaust as well.

Which oil cooler you going for? And how are you plumbing it in?

Well I've started having a look not sure which is the best way to go, air or water cooler.

I'll phone Think Auto I think for some better infotmation.

I think water cooled is better if your water temps are fine and the rad can cope.

Let me know as I have the same engine and want one.

I just couldn't work out where to fit it onto using an after market cooler.

Yea sure I'll let you know what I go for.

[Edited on 5/7/15 by Neadles]

Thanks

These engines are very sensitive to fuel mixture, I would try raising the needles by a notch, when it was rolling roaded was it in a very hot room?

Aftermarket cooler use a take off plate in place of the original water cooler.


In situ with pipes


Height comparison


Oil cooler in place

My father in law is having the same issues with his fury blade.

Like you say, it runs fine until it gets hot.

Does anyone know whats actually happening to cause the stuttering other than, 'something is getting too hot'?

My indy has never had this problem with the same engine which seems odd

Sounds to me like the fuel is boiling in the float chambers. What is your intake arrangement... sausage filter under the bonnet? Cold air feed to the intakes is the simplest solution.

His has a sausage filter, I think the bonnet actually squashes it down a bit too as it is tight on space.
I'll tell him to get some cold air feeds run in to cool the intake area down

His has no bonnet vent whereas my indy has the bulge and vent on the front allowing the cool air to hit the filter and carbs... so makes sense!

On the Indy most of the exhaust manifold is external as well, where on the Fury most of the heat from that is trapped under the bonnet.