We get involved with the Mini 1275 engine today for a change, but it’s not long before we check out another Cosworth. This one blew up on the dyno after a rebuild!
40+years ago I had a Cortina 1500 GT engine rebuilt and had no end of issues which (with hindsight) were almost certainly all due to good machining but totally overtight clearances especially in the bores...
Another great video Lee, your attention to detail wins the customers confidence. Working with such fine tolerances have you ever considered becoming a part time dentist.. :)
As a mechanic I am seeing more and more engine problems and one of the first questions we ask is Has it been remapped ? , .Some are quite open , some are evasive, as if that is going to make the repair cheaper. The question people ought to ask themselves is why did the manufacturer not increase the power ? They most likely did during development and then dialled it back for longevity... A3 Tdi and 1.0 eco boost seem to be the flavour of the day at the moment . It used to be A4 TFSI but all the mapped ones seem to have disappeared in a cloud of shrapnel within the cylinder head. It appears that everyone with a Dyno and laptop can out perform the next , and if it goes bang , it must be the machinists fault or the engine builder.. Hey ho keep up the Videos 👍👍🤏
90% of the reason of de tuning from factory is to meet all the emission laws nothing to do with longevity that's the main reason most tunes require dpf/cat removal ect. That engine seemed to destroy itself due to being poorly built in my opinion
@@philhermeticsuppose you could say fairly new to the game with only having remapping experience for 5 years. Mainly on VAG group cars as I only work on my own stuff(yet to blow an engine up) that’s what my opinion is based on. From this video and what he says would lead you to believe that this was caused by the mapping and not the tight and inconsistent tolerances on the bottom end?
I must agree on that. If racing you want every HP possible long enough to finish. Idiots want that bragging rights number, but even with expensive internals they stress them. And then a lot of blame goes to the idiot holding the steering wheel that requested a very aggressive tune, and then uses it.
@@sliceandhopegolfU have to be one of the tooner crowd. The OEMs have a bucket full of considerations to balance in designing and mapping their engines. An engine is a wheel barrow load of compromises. The OEMs have to balance emissions, fuel economy, driveability and durability with the intended market segment. What is expected of a dialy driver vehicle to pick up groceries or the kids is much different than a high end sports car. Industrial and say rail engines or ship engines are actually high performance engines in their own right. HP figures for the displacement may appear low, but the intended use dictates heavy parts for durability. That keeps the RPMs low, but torque is high. These engines run for years with oil sampling, tuneups and head swings. Many are in place for decades. Fuel economy is a prime concern, and most are actually fairly efficient for the tas they do. Regarding DPF delete, most of the tuners are increasing fuel in the combustion chamber causing "rolling coal". That increased fuel causes higher particulates in the exhaust which would plug the DPF. Now a number of these tuners have been hit with big fines and pretty much forced to shut down due to violating emissions regulations. Look at the situation with initially VW and their emissions test bypass software screwup. But it was not just VW, most of the German manufacturers had a finger or two in that, just VW got caught at it. That got the EPA looking at diesel tuners.
Lee keep the old school ford engines coming we luv'em. Don't bother about those rotten french engines or those transit engines made of toffee. I've got a couple of 1600 crossflows and a 2 litre pinto that could do with a quick rebuild for nought. Now to go and comment on someone elses comments because we know that you love it🤣
I used to pretty much always get my rods on bottom size and grind the crank to top size to get the minimum big end clearance. This does not work on a lot of fords as they seem to end up with no clerance when you do that. I prefer minimum clearance on the big ends as its good for oil pressure plus i figure the way the rod moves when running to much clearance will allow it to hammer and shorten its life. I have always done this on literally thousands of cranks rods etc and never had a problem. Putting the rods on bottom size will also give the bearings maximum nip so less likely to spin a bearing up if the engine is abused somehow..
Good job you're easing off 😂 Got to admit I'm fed with seeing your gob when l log onto RU-vid 🙈. Too relentless for me....? ...I'm out for a breath..phew
50% Bob weight on V8 90 degree cranks, I5 Cylinders, V4 and V2 engines I believe. Sometimes best left to people that do that stuff all day for obvious reasons.
Would be interesting to measure bore distortion with the head on the block torqued to spec. Some of these distort the bores when the head is clamped down
Correct...the touring car boys from the 80's always had their cozzy engines 'torque plate bored' so the bores would align & measure perfectly when the head was on & torqued.👍
@@redchemicalsltd2324 yes, the distortion is quite significant especially when the tolerance is considered, but I have seen a fairly round bore distorted after honing. Always pays to hone it with the clamp plate fitted. Wonder what the honing was, that is a whole new set of problems waiting to happen
The marks on the mini block face are from the head gaskets..... every 1275 gasket ive ever seen has the holes for 11 studs.... its the gasket thst leaves the mark....
Always thought it was a bad idea to take a freshly rebuilt engine to a dyno and rev the boll*cks off it! That is an odd looking 1275 head, what is the casting number under the rocker shaft, it will be 12G XXX or similar? Phil
Who’s the best for Sierra Cosworth petrol pipes off the tank, the big ones available from GGR etc but the small one next to it I can’t find one ?? Cheers 😂 P.S seeing as the Cosworth guys hang around here
Take your car for service to the main dealer Yeh mate just send the invoice and ill pay it next month when i get around to it A few options , no main dealer service It is cod , you havent paid so it doesnt get released , if you dont have a card then no prpblem here is the bank details , it will be released once payment cleared +20% for an account due 7 days and 10% late fees Stop credit , no further work till account is paid in full Your problem of how to pay is not our problem
Re: the camshafts being scrap, they aren't really if you consider spray welding new bearing material and today spray welding is not the insanely rare repair it was years ago and anyone with a decent setup can reapply good solid metal to a camshaft. Its funny, in the US when a vintage camshaft gets beyond usable, they send it down the road to a spray or spatter welder who rebuilds the bearing faces and the cam lobes and bingo bango as good as factory camshaft. You used to be able to get Pinto camshafts spattered I seem to remember but now its just chuck it away...
Why have you turned off comments on the "SAD & GUTTED to be saying bye to our apprentice on the channel!" video? Is Isaac leaving or not? If not, the title is misleading
Think that Cossie is a combo of bad build and a bad map. It may have survived one problem (not for very long) but the 2 of them, well, theres the result.
There seems to be an air of mystery to your recent introductions, keep em coming, on the cossie motor if only the customer had come to you guys first, you'd think by now anyone with a cossie motor would be on the phone to you first. Looking forward to the rebuild of that one should it go ahead
hi lee on a couple of 1275 I did adding the 2 extra head bolts when the head was torque down I found it tighthed the Crank so a line bore was required, it may have been because those blocks had been hot in there previous life.
On that same train of thought, I was left questioning the order of operations, for finalizing the bores, squaring the block, etc., (previous to their getting the engine) before the addition of the two additional studs, for the probability of bore and deck distortion.
On that same train of thought, I was left questioning the order of operations, for finalizing the bores, squaring the block, etc., (previous to their getting the engine) before the addition of the two additional studs, for the probability of bore and deck distortion.
The ultimate rookie fail i ever saw was a daft laddie who fitted a 1.6 Golf GTI head onto a 1.6 normally aspirated engine and it struggled to turn over . I got called out and after a few minutes not believing what i was seeing i said to him , more out of devilment " lets do a compression test " as he was wanting a second opinion on the cam timing . The tesr showed off the scale 😅😅😅 A carburettor golf 1.6 is flat top pistons and a chambered head , A gti golf 1.6 is flat head and chambered pistons ( like an old diesel) . So we had about 36-1 comp ratio . 😂😂😂🎉
Far too many think a cast iron blocked Pinto with a 16v head is some kind of work of art. It's about as basic as they come. As long as there are the 'Cosworth police' about and the many so called specialist that you 'need' to repair/ rebuild one prices are always going to high. Any decent engine builder with an ounce of savvy can rebuild this engine. It is so very ......simple...
You buy a car with 150 bhp. The manufacturer has designed that car for 150bhp.if they could get 200 they would simple economics 200 bhp for no extra cost and sell more. But they don't. They might have a 5 to 10% buffer for reliability. In comes Kevin with his mapping machine and thinks he can do better than a million pounds worth of rnd . Woooow yea you got 230 bhp. With a few mods. And then poof when you try to use that extra power for any length of time. Idiotic. Want extra hp. Buy a car with that hp. Or swap out the engine the gearbox the trans the suspension the brakes. Hmmm buy a car with that hp.
these old engine clearneces are hourendous. Im lucky. stock bearings and stock crank stock tolerences rods and pistons in a 4cylinder honda engine i made just over 1100bhp. no ballancing or anythign. I am now having head issues so moving to copper gaskets now.
Knew a fella once with a small collection of Mini magnesium alloy gearbox casings. Originally from way back 1959. BMC were going to make it the standard material for production but it didn't pass the accountants test, too expensive for production. Urban myth is a few hundred reached showroom floor in 1959. But dimensions all changed so can't be used for later 1960's gear clusters and diff etc., without major expensive machining.
I think on a V8 you need to add weights to the journals to simulate the pistons and rods before you can balance it. It can be done but it's probably not worth the time when you're working on different engines. Probably sends them to a Rover V8 specialist who will have the proper gear.
Cheers Lee, always going to be these problems because essentially these Engines are bespoke. I remember when I used to Fart about with the Pinto in Ford Cars, they were very forgiving, you could get away with a lot of near enough and they still ran fine. See you on the next one me old Gudgeon Pin.
@lee those space heaters you have in the roof are super inefficient compared to new ones, you'd save the cost of replacement in a year or less with the right ones
@@fatwalletboy2 Well yes but how are they more efficient? Do they use heat pumps instead of direct heating elements? Electric instead of gas? It's worth noting that all electric heating elements are 100% efficient in that they convert all the electricity to heat.
Each for the cassie owner. Are older engines such as xflow that sensitive to build tolerances and if so how on earth do the factories get good engines with no component selection or balancing....its it because they just rely on tolerance variations....some lucky customers get a good mix and some unlucky a shite engine?
It gets it wrong so often that I call predictive text “autocorrupt”.😂 My other bugbear is voice to text. The correct words flash up on the screen then it alters them to some random crap, WTF!? It boggles my mind how it initially gets it right but then second guesses itself to choose the most bizarre combinations of words as a “better” or more “logical” option.
It appears to me that when the piston touched the head it squeezed the oil film off the rod journal. It certainly wont run too long with the bearing rubbing the crank without a layer of lubricant between them. It is always important to have some room for the piston to rock and pull away from the crank journal. The deck height is always a guess but if you know how much the piston expands up you can add all the clearances together. On some engines 3 on mains 2.5 rods .5 pin the rock on the piston another 5 or more depending the size of the bore. How much more for heat expansion 5 or 10 ? Aluminum expands twice the amount of cast iron block. Now combine that with someone running 0 deck height and your depending on the gasket to keep the piston from kissing the head.