engine number

[types26/36]

I think the idea of 4 slots on the lotus shaft is to get more oil up into the head.

Yes you are right about the Lotus jack shaft having more slots and it is so it gives 4 squirts of oil but I thought you were talking about the bearing in the block
I have used the single slot jackshaft and I have also had more slots milled in them as well,I dont think it makes a lot of difference as even with the single slot plenty of oil gets into the head to the point where we use to fit a restrictor in the block with a 90 thou hole to limit the amount of oil being fed up to the head.

[M100]

I think the idea of 4 slots on the lotus shaft is to get more oil up into the head.

presumbly to avoid it leaking out of the sump

Funny how small details like this don't seem to have been mentioned in any of the relevant books like Robinshaw/Ross and Wilkins, or have they?

[Dave-M]

pmpsantos, getting back to your problem, If the engine number is important to the use of your car I would suggest you pull it out as soon as you buy the car and strip it, then post pics on here and it will be identified correctly. The engine number should be on the registration document and it is not going to be the crime of the century to stamp it onto whatever block you decide to use.
From what you say it is almost certainly not the original block but as I said before dont build the engine on standard cortina crank and rods if you want it to perform and last as it should.
Best of luck, 2 plus2's not bad!
Regards
Dave

[pmpsantos]

Thanks to all!
I'll buy the car, I've see the head today it's a "big valve" with 2 webers 40. I'll do what Dave says, but first you see photos, I promise!! Thank you again!!

[pmpsantos]

Hi!
The day arrive!! I?ve got it!
Now you can see the photos...if I know how to put these...
Let's see...[/img]
Ok let's see!
This is the engine (ugly hein???) ref:120E60615 and thi head? it?s really a big valve or it?s only the cam cover? Which engine block is easier to use this head?? Thanks again!

[Dave-M]

It's an old pre crossflow engine, best bet is to find a 711m crossflow block and build your head onto that. Have you got the front covers and all the other bits?
Has the previous owner got the original block?
It's all going to cost a fair bit of money but if the engine in the car is running OK why not keep it and drive the car while you sort the Lotus bit out.
Regards
Dave

[types26/36]

Hi!
it?s really a big valve or it?s only the cam cover? Which engine block is easier to use this head??

Difficult to say if its a B.V. head as the 26E 311 is only a casting number, best to look at the raised boss near no 1 cylinder to see if it has a "N" stamped on it (although this is still not cirtain) measure the inlet valves (39.6mm from memory) and check the number of rings on the camshafts. (2)
The easier block to use would be the 120E but not the best as the 711 involves more work.

[pmpsantos]

Hi thanks again! One simple question (for you...) Which cars bring the 771M block? cortina 1600 MK2? I'll look for one block and when the AMAZING ENGINE is mounted I'll change engines...

[types26/36]

Which cars bring the 771M block? cortina 1600

I think you mean the 711M engine, there IS a 771 known as the "Valencia engine" but as I recall it was a version of the Kent 711 engine fitted in the early Ford Fiesta and was a front wheel drive, although it is simular to the 711 the mounting points are different.
The 1600 cross flow was around from about late 1967 but the 711 block only came early 1971 and were in the rearwheel drive Escorts,Cortina and mk 1 Capri's.

[pmpsantos]

Hi! many time no speak!!...
I've decided to built the engine with the twincam head, I looking for a 711 block, but wich is the best the 1.5 that the car have or this one? Can you resume the modifications on the 711 block that are necessary to do? Is the 1.5 block exactely like the lotus one? can I may only put the head above and that's ok? And if it is the big valve?? It works well? How can I easily confirm that it's a big valve?
Sorry for the lots of questions, but I need to take a decision, buy a 711 block, or use the one I have (think is a 1.5 cc from a cortina Mk1 GT)...
Once more thank you very much!!!

Pedro.

[rgh0]

Hi Pedro

There were a range of Ford 1500 blocks used over the years that the Lotus twin cam engine was originally built on. They were all Ford 1500 block versions which are slightly shorter in height than the various vesions of the Ford 1600 blocks but otherwise the two types of Ford blocks are interchangeable. The Ford 1600 blocks of which the 711 block is most commonly available can be used to build the engine but some modifications around the front timing cover to include a spacer and longer timing chain are required to accomodate the taller block. Fitting the overall taller engine into the car and clearing the bonnet also requires some small adjustment to the engine position by slotting the engine mounts in most cars.

The article at the link below provides some more detail on the alternate blocks.

http://www.lotus-cortina.com/library/block/blocks.htm

The Dave Bean catalogue also provides details on the various combinations of cranks, rods and pistons you can use to build various capacity engines in the 1500 or 1600 blocks. If your building a Lotus twin cam engine this catalogue and the Miles Wilkins book on Lotus Twin Cam engines are both essential reading in addition to the workshop manual

The simplist engine build is to base it on a Ford 1500 block bored to Lotus standard 82.5 mm and use standard Lotus / Ford crank, Ford 125E rods and standard Lotus twin cam pistons for the Lotus standard 1558cc engine, however many other combinations of blocks, rods, cranks and pistons possible for engines up to 1760 cc relatively easily or even up to 2.2 litre with special alloy blocks if you want to spend the money. Lots of discussion in the archives on all these options

cheers
Rohan

[rgh0]

Pedro

In rebuilding the cylinder head it does not really matter whether its a big valve head or not to start with as normal practice is to rebuild heads to the big valve specification these days.

Apart from the cam cover the other ways to tell what you have are as follows.

Big valve type D cams orginally had 2 grooves on the boss behind the chain sprockets but many cams now reground so no guarrantee any more. You really need to get the cam lift and duration measured to verify what sort of cam you have

Big valve heads orginally machined slightly thinner than the earlier heads for a higher compression ratio but all heads have now had at least one refacing so thickness is not any real indication. when building an engine you need to measure head thickness and combustion chamber size to ensure you get the compression ratio you want in combination with the block, crank, rods and pistons you are using

The letter stamped in the boss on the top of the head next to number 1 cylinder is indicative of the engines orginal build specification . Lotus used a range of letters for various engine types, N was a common letter for big valve heads and is consistent with a red ribbed cam cover. Page 181 / 182 in the Wilkins book provides a listing of all the head stamp letters

The inlet valve head diameter in big valve engines was 39.6 to 39.7 mm diameter compared to 38.8 to 38.9 mm on the standard engine.

Hope this helps
Rohan

[dusty]

Can someone tell me where on the engine the engine number is stamped?

According to lotus records my car left the factory with engine number LP10983LBA and i want to see if it still has this engine?

Cheers
Jon