Not original head identification help

[LabroDF]

Knowing my motor was rebuilt/modified in the late 90's, I have looked few times to see if the original motor was replaced. The head specifically, the LP# was not located and that area was blank. Moving the mirror around I recently found "BVBH366" in the back corner, can anyone help identify this # code and provide any information?

Thank you,

Dennis

[rgh0]

There were three "normal" head numbering schemes at the rear of the head i am aware of. There may be others and the date ranges may be wrong as so many head changes have occurred to cars over time its hard to tell what was original with any degree of precision. Lotus also did some LP xxxx numbering and /or dating of heads on the bottom face rather than the rear face during the first period for some reason.

1. The LP xxxx number the same as the engine ,,,, S1 S2 and some S3 engines
2. Nothing ... some S3 and S4 engines
3. An alpha numeric number scheme of the form AAXX ... Some S4 and later

The numbers on your head don't fit any of these but it may have been a non numbered head that has been later numbered perhaps by a shop doing a rebuild for identification purposes. Alternatively it could be a non "normal" original numbering scheme that Lotus did at sometime for purpose.

cheers
Rohan

[LabroDF]

As always Rohan, thanks for the insight.

[oldelanman]

Similar head stamping has been mentioned before....

viewtopic.php?f=39&t=18533

"One of the photos did bring out some detail that I couln't read, before: the number stamped on the cylinder head is not VBH70 as I previously thought, but BVBH70. I'm speculating, but does 'Big Valve Brian Hart, 1970' sound plausible?"

[LabroDF]

Interesting, thanks for the post.

Speculating here,.. The owner of this car was well off in regards to $$, I have letters from the owner to Dave Bean (the shop part of the business) stating he is looking for high performance which the PO would spare no expense for more power..

What would be the best route to determining if this is a Brian Hart head? Are his heads common?

Thanks in advanced.

Answered my own question with the search button.

viewtopic.php?f=12&t=17939

[Elan45]

BH 607

BH 607

BH 607

I was told back in 1978 when I bought my pre-airflow coupe that the head had been damaged and replaced by a "Cosworth" head that I got as part of the engine that came with the car. I never thought the BH could stand for Brian Hart, but here is the number stamped into the rear face of the head.

[rgh0]

Yes measure up the head to see whats been done and how it compares to a Hart head. The advantage of a Hart head is its the most you can get out of and original head casting, no one has done any better. The disadvantage is that its very fragile and was really only intended for a race weekend or maybe two.

The McCoy conversion and the modern Dave Bean, QED and SAS head castings get similar power with much better reliability as they have more metal left to hold it all together

Cheers
Rohan

[rgh0]

DSC04203.JPG

DSC04203.JPG

DSC04203.JPG

I was told back in 1978 when I bought my pre-airflow coupe that the head had been damaged and replaced by a "Cosworth" head that I got as part of the engine that came with the car. I never thought the BH could stand for Brian Hart, but here is the number stamped into the rear face of the head.

An interesting series of numbers on the back of the casting

Maybe DL25 was the original Lotus head ID number re-stamped after the rear face was ground clean as it fits that AAnn format and then SBH 607 was added when the head was modified by Hart. I dont know how many types of heads Brian Hart produced but I have seen reference to the 416B engine as the Big Valve Hart engine and thus the BVBH designation may make sense. The SBH 607 may make sense in the context of a Sports Brian Hart head supplied for an Elan

All just speculation

cheers
Rohan

[Elan45]

When I bought the FHC in 1978 and was told about the replacement head and the fact it was necessary due to the PO installing too hot a plug and damaging the original head and a piston and there was also another pair of cams in nice rough made wooden boxes marked L1 and one of the cams had been modified into a special, high performance 2-piece "racing" cam. LOL But the head still has normal original small valves and the ports still show sand cast surface. It just does not appear to me to have been modified from stock.I intend to use it w/ the coupe's original block when I build its engine this summer and it will be as near stock.

On the other hand, I bought another TC engine in 1985, supposedly built by Gus Huchinson back in the day and it is a piece of work with larger valves and polished ports and destined for my other S3DHC that the original owner modified to 26R spec in the late 1960's. This HRA engine was one of two engines that were part of a genuine 26R that was here in Columbus in the 1970's. The last Columbus owner separated this engine from the package, when the car was sold with the intent to install it into a rally Cortina. There was a change in plans and I was able to buy it.

Roger

[LabroDF]

I did some brief research and gone through some history, will look more today.

I have determined that all parts and labor for the rebuild was supplied by Dave Bean. In regards to the head, I did not see anything specifically in the history but I did find a detailed letter to Dave Beans shop asking to supply Cosworth parts etc.. I'll try and upload the letter, maybe it can explain a little more in regards to what other parts were purchased, valve sizes.. I'm no expert when it comes to a engine rebuild.

[avro]

The attachment DF43D9C7-1664-4FC3-96BF-938572E1A447.jpeg is no longer available

Similar head stamping has been mentioned before....

viewtopic.php?f=39&t=18533

"One of the photos did bring out some detail that I couln't read, before: the number stamped on the cylinder head is not VBH70 as I previously thought, but BVBH70. I'm speculating, but does 'Big Valve Brian Hart, 1970' sound plausible?"

It hadn?t occurred to me until reading this topic that l ought to check out an old scrap head that l had tucked away. I had been told when it came into me on a blown race engine many years ago that it was a Brian Hart Head.
I have just found that it also has the BVBH stamping on the rear.
It has unfortunately had a rather hard life, having sustained frost damage to the rear and been welded and later a dropped valve. ( beyond welding)

Nick