There's a vast amount of NGK spark plugs that are fakes . So good even motor factors as well as eBay have been fooled by them . Prone to failure, now I'm not saying it's the cause of your issue but if the centre electrode has let go it's possible that's done damage to bore. I've run Denso plugs for some years now and find them better in my motorcycles for what it's worth . I've never seen a centre break loose like that in all my years on spanners with both bikes and cars . With a 1293 tuned mini I once had running NGK plugs the bugger wouldn't start in cold weather, turned out be plugs , be fine all day once run once so since then always had a little thing about NGK plug heat coding . Replaced with champion plugs ( yeah it's a few years back Lol) and never had an issue with mini again . This is an informative reply from a 40 plus year dude on spanners , bikes and cars plus bike race mechanic for a few years , not an armchair diagnosis of failure . If you have batch of plugs bought at same time change them just in case . I retained some of the good old catalogue,s for spark plugs from the 1990's before we went digital and can cross reference plugs for you if needed . Ordering stuff today for vehicles I find older engine design using thinner spec oils , different grade of plugs etc yet the design not changed other than management systems and more sensors .
Something that i learnt in the past is that a high revving water pump (small pulley) can make a frothing of coolant in the system that creates air pockets.. Doesn`t seem to be related to this but i thought i would mention it. Are you using a standard radiator with the long filler neck?
To be honest the water did look like it had a lot of air in but possibly by boiling? The engine ran on the dyno with the water pump with no problems so I assume that it ok. My radiator is an alloy version and has no fill point on it, only on the thermostat housing on the head. This I think is the route of my problems….
@@Tomkitek Ahh..As in the case of most competition front mounted radiators on rear Imp engines..A header tank is a must in the configaration.. On my Mk1 Cortina (1500 pre-crossflow) i have a slimline Fiat radiator that has an in-line filler horizontal filler affair with tiny rad cap in between the top hose .The Fiat rad has a outlet for use of a outlet at the bottom for a header take.
Had to do similar with a little fiat I used to race. A lot of overheating problems. Header tank was too low. Raising it higher than the engine cured the problem.
Totally gutting, let's hope there's no lasting damage to that beautiful engine. I've never seen a 'spark plug' like that before...impressive! That needs to be put on a plinth or made into a a trophy for something! What ratio diff do you use, or is that a trade secret?
I’ve had the head off and I don’t think it’s too bad. A piston ring at worst I think. The silver lining is I’ve finally found the problem with help from SRD. Yeah I’ve never had the insulator part break off. Properly knackered!!!! The diff is a 4.11 ratio. At snetterton which is a very long straight it hits about 7500 rpm so just about perfect 👍
@@Tomkitek can't say that I've ever seen a naked spark plug before!!! I'm sure SRD will get it sorted then you can get the cooling system sorted too. Standard MKIV Spitfire ratio. Didn't know if you'd be using one of the longer ratios for some circuits. I've got a rare 3.27 GT6 diff sat under my workbench which I was going to use in my MKIII Spitfire resto, but probably a bit long!
just make sure the header tank is as high as you can get it. ours was almost kissing the bonnet and if you want to cover your arse 2 ways my 1600m race car was fitted with an after market swirl pot as well hopefully the engine survived without bending your credit card to much.gary j [dave karaskas racing]
Yeah I’m going to try and get it as high as I can on the bulk head. I’ve had a look at the engine and think it’s ok to be honest. Not too much problem I think and hope!
There's a vast amount of NGK spark plugs that are fakes . So good even motor factors as well as eBay have been fooled by them . Prone to failure, now I'm not saying it's the cause of your issue but if the centre electrode has let go it's possible that's done damage to bore. I've run Denso plugs for some years now and find them better in my motorcycles for what it's worth . I've never seen a centre break loose like that in all my years on spanners with both bikes and cars . With a 1293 tuned mini I once had running NGK plugs the bugger wouldn't start in cold weather, turned out be plugs , be fine all day once run once so since then always had a little thing about NGK plug heat coding . Replaced with champion plugs ( yeah it's a few years back Lol) and never had an issue with mini again . This is an informative reply from a 40 plus year dude on spanners , bikes and cars plus bike race mechanic for a few years , not an armchair diagnosis of failure . If you have batch of plugs bought at same time change them just in case . I retained some of the good old catalogue,s for spark plugs from the 1990's before we went digital and can cross reference plugs for you if needed . Ordering stuff today for vehicles I find older engine design using thinner spec oils , different grade of plugs etc yet the design not changed other than management systems and more sensors .
Yeah I’ve never seen an insulator break off like that. I’ll see what the engine builder comes across….
Something that i learnt in the past is that a high revving water pump (small pulley) can make a frothing of coolant in the system that creates air pockets..
Doesn`t seem to be related to this but i thought i would mention it.
Are you using a standard radiator with the long filler neck?
To be honest the water did look like it had a lot of air in but possibly by boiling? The engine ran on the dyno with the water pump with no problems so I assume that it ok.
My radiator is an alloy version and has no fill point on it, only on the thermostat housing on the head. This I think is the route of my problems….
@@Tomkitek Ahh..As in the case of most competition front mounted radiators on rear Imp engines..A header tank is a must in the configaration..
On my Mk1 Cortina (1500 pre-crossflow) i have a slimline Fiat radiator that has an in-line filler horizontal filler affair with tiny rad cap in between the top hose .The Fiat rad has a outlet for use of a outlet at the bottom for a header take.
@@limjamrace Yeah that’s interesting. Looks like I’m on the way to solving the issue then!
That sounds like a good shout - water pump cavitation at high RPM. A larger water pump pulley would reduce the risk.
😢Good luck hope all goes well
It’ll be right in the end 🫡
Had to do similar with a little fiat I used to race. A lot of overheating problems. Header tank was too low. Raising it higher than the engine cured the problem.
It’s crazy how little a change makes all the difference.
Totally gutting, let's hope there's no lasting damage to that beautiful engine. I've never seen a 'spark plug' like that before...impressive! That needs to be put on a plinth or made into a a trophy for something!
What ratio diff do you use, or is that a trade secret?
I’ve had the head off and I don’t think it’s too bad. A piston ring at worst I think. The silver lining is I’ve finally found the problem with help from SRD. Yeah I’ve never had the insulator part break off. Properly knackered!!!!
The diff is a 4.11 ratio. At snetterton which is a very long straight it hits about 7500 rpm so just about perfect 👍
@@Tomkitek can't say that I've ever seen a naked spark plug before!!! I'm sure SRD will get it sorted then you can get the cooling system sorted too.
Standard MKIV Spitfire ratio. Didn't know if you'd be using one of the longer ratios for some circuits. I've got a rare 3.27 GT6 diff sat under my workbench which I was going to use in my MKIII Spitfire resto, but probably a bit long!
just make sure the header tank is as high as you can get it. ours was almost kissing the bonnet and if you want to cover your arse 2 ways my 1600m race car was fitted with an after market swirl pot as well hopefully the engine survived without bending your credit card to much.gary j [dave karaskas racing]
Yeah I’m going to try and get it as high as I can on the bulk head.
I’ve had a look at the engine and think it’s ok to be honest. Not too much problem I think and hope!
Can't you vacuum fill the coolant system?
I probably could with a header tank?
Wouldn't it work with what you have currently?
Just chucking ideas out there.
@@DavidMalenczak Possibly but it may be that I don’t have enough expansion to cope with the heat rise
LFG!
Let’s go Torque Squad 🫡
@@Tomkitek WE ARE @TorqueSquad !