Cosworth Mk 16 engine & Modern Counterpart

[SJ Lambert]

G'day everyone

I'm just wondering what the assembly date for engine no. LP 5332 might have been?

Some time in 1966 or even '65 is my guess.

The engine in question is a Cosworth Mk XVI Lotus Twin Cam - so it may not be able to be accurately dated, but even if there are Elans out there with engine numbers roughly either side of it with known assembly/1st rego dates, i'd be interested to know!!

LP 5332 went into an open wheeler in Australia that was finished late in '66, it's possible that the engine could have pre-dated that by some time though. I'll Make a "B" motor to modern specs to run in conjunction with the original Cosworth unit

Cheers

James

[elanfan1]

There is no logical progression date wise with the engine numbers however 2 close numbers are:
5327 7th march 66
5392 28th February 66

HTH

Edit;
Have just found it! LP5332 went in Unit 5542 on 30th March 1966

[SJ Lambert]

Thanks elanfan1 - were their ever engines/cylinder heads with the prefix IP instead of LP?

[SJ Lambert]

Ooops - having gotten my grubby hands on said engine I've discovered the Cosworth engine number on the block which according to numbering system mentioned in Robson's Cosworth book makes it a January 1966 built unit.


Cheers

[SJ Lambert]

Renold (In Australia) tell me that they've been out of the Twin Cam Sprocket making business for a while. Does anyone out there have a preferred manufacturer and supplier of crank sprockets ( all sprockets really) and chains for race motors. I'm not necessarily looking for for a vernier set up, would like something that's light weight and capable of hanging together and in place at high revs. Will be looking to put a set up back onto this Laystall crank as well as onto a narrow pin crank as well.

Age stamp on crank is Nov 65

[rgh0]

QED, Burtons or Dave Bean plus the other usual suppliers should ll be able to supply all the sprockets and offset dowels. I recently got a vernier sprocket set from Burtons just to try it verus offset dowels that I have always used.

The standard sprockets work fine at 8500 rpm

cheers
Rohan

[SJ Lambert]

Burtons and I are getting on well at the moment!! - they offer steel sprockets for the cams at least!

[SJ Lambert]

The relief work at the back of the block for the Laystall crank isn't too severe.



Have had to take more out of a couple of spare blocks to relieve a BDJ crank.











I suspect the BDJ crank has the least amount of "back cut" on the lip of the rear counterweight - have only got a millimetre of clearance so far, so will take a bit more out of the blocks for safety's sake. Will use the extended front cap set on one of these for a Holbay S65 copy (with a Cosworth style low transfer/idler gear for the cam drive ) (that'll be an iron head non Twin Cam motor) and put a standard steel set on the other block for an uprated Twin Cam engine. I think I might just check the counterweight clearance on the Mk 16 too!

[SJ Lambert]

This is the second standard block - am pretty happy with the clearance this one is now showing.

[rgh0]

Looks a lot like the grinding I do on 120E blocks to fit the Datsun L16 crank

cheers
Rohan

[SJ Lambert]

Dropped 3 engine blocks (all 120E castings, including the Mk 16) and two cranks, two sets of steel caps and a gear cam drive for the pushrod Holbay clone motor off at the machine shop today, then ducked and ran for cover.......................

[SJ Lambert]

I haven't checked 'em yet, but I presume this engine is equipped with L1 camshafts. I imagine that correct tappet setting is 10 thou?

[rgh0]

Yeah the nomaal L1 cam clearance setting was 10 thou. If you have a cam you want to get checked to confrim its profile you can take it to Clive Stenlake at Clive Cams and he can measure it up on his cam measuing machine to give you a detailed profile ( for a price )

cheers
Rohan

[Panda]

Hi , Paul Truelove at Fourd Performance in Sydney has a good stock of chains, sprockets etc of very good quality. I have no connection, just a happy customer. He has just supplied me a 90mm bore alloy block and lots of other goodies to build my new race engine. All very well priced.

Alan P.

[elj221c]

Yeah the nomaal L1 cam clearance setting was 10 thou.
Rohan

I never thought that I would disagree with Rohan on an engine issue but I suppose there is a first time for everything?!

I posted the Cosworth spec sheet here elan-f15/cosworth-and-specs-t21665.html.

The cam timing is based on a clearance of 10 thou, page 2, but the actual valve clearances are shown on page 3.

The BRM cam written notes are mine, the information I acquired in '76, along with the Cosworth spec sheets, when I bought new rings from them for their 83.5 forged pistons.