cossie51

After a little help working out what caused the backfire in my intercooler.
I pulled away from a junction in first gear on light throttle and just as it made positive boost I heard a loud pop and car was flat. I thought a hose had popped off but then found it had split the cooler.
I'm running pectel T2 with a coil pack

Anyone any idea what would of caused it to explode in the cooler ?

lacey

Where did it split ?
Along a weld or a tube ?

cossie51

It split down the weld on the end tank turbo side and bent the aluminium open.

Caddyshack

What type of intercooler is it?

cossie51

It's 100 mm airtec 500 style cooler. What I'm trying to work out is what caused the backfire in the inlet side !

costina

iTrader: (1)

Would like to see pics if possible.

cossynut2

That is something I have never heard of before, it sounds like air pressure was going into the intercooler but could not get out again and burst open the weld? A backfire is normally through the exhaust? I had an intercooler hose come off once as it had not been tightened up properly which was a simple fix. I would have been the same as you and that would have been my first thought for what happened.

cossie51

This is what I found once I removed the intercooler

costina

iTrader: (1)

That imo looks like a poor weld cracked right at the centre.

Can you see any evidence of an explosion?

ajamesc

Looks like it's just split send it to spec-r to be welded properly lol

cossie51

It was at about 4 psi when it went pop with quit a loud bang as I was just pulling away from a junction in first gear gently. It has split the weld holding the 2 parts together at 90 degrees. This is the second time it's happened at the same point. Last time it was welded up by a specialist welding company so don't think it was the weld at fault. Plus it's not just a cracked weld, it's bent the metal both sides of the weld so was opened up with some pressure.

costina

iTrader: (1)

Looks like it has no penetration on that weld at all just laid on top.

ajamesc

It could have been at fault for ages and slowly working it's way to popping. The little bit of boost you put into it could just have been the straw that broke the camels back. Just get a new intercooler or try having it welded again

cozzy jeff

iTrader: (4)

thats not a 100mm cooler from airtec

cossie51

It has airtec stamped in to the metal across the top of it and airtec painted across the front of it so I think you will find it is an old airtec cooler.

cozzy jeff

iTrader: (4)

it may well be an airtec but its not a 100mm one,the 100mm ones have the pipes coming from the top of the cooler not the back.

cossynut2

To me it looks like it was never seam welded properly from new. My Spec R intercooler has been in my 2wd Saff for 20years and has never given any problems.

Caddyshack

Surely to pop open it would need to have the inlet valve closed when making boost, unless it was a faulty weld. Probably worth getting the timing checked and also a leak down test at same time.

I assume there is nothing in the inlet track that could ignite which could cause a back fire in the inlet?

pectelboy

This was an inlet miss fire on a rs200

Caddyshack

Wow, what causes that...does the fuel ignite under heat, spark or compression?

I like the adjustable spanner next to it in the shot....I think it gonna need more than that to fix it!

Adam-M

Holy crap did any particles of alloy make their way into the engine or where you lucky?

costina

iTrader: (1)

Toby thats a special adjustable in metric and imperial...........😂

pectelboy

Iam sure Dave Jackson had the same problem in his race car , it's a misfire in the inlet but didn't know what caused it

Caddyshack

That will be fine then, Paul....should have noticed

turbotrev

Wow Ive never seen a cooler split like that before!

Cheers Paul

grcossie

Have seen it before. If you have overfueling, it can cause this. It`s alot of Pictures on Google

cossie51

He did at croft in the warm up session of time attack a couple of years ago.

Caddyshack

Would a time attack car be purposely set up to over fuel for some reason? You would assume it would be perfect unless something went wrong?

cossie51

It wasn't set up to over fuel, it had a misfire from a faulty plug and when running 8 greys and 800 + bhp there's a lot of fuel in the inlet. Problem was solved with different plugs and converting to coil on plug. Car ran fine after this was done.