11 replies to this topic

[metro1275]

what does anyone know about this camshaft? what will it do to my 1275 a+

Thanks in advance

[Retro_10s]

If I remember correctly... the 649 was originally designed for 998's

So it'll behave like a fast road cam, A bit tamer than a 286 though.

Bear in mind you might need to change oil pump too depending on the drive.

P.S.> it's spelt leyland

Edited by Retro_10s, 12 October 2006 - 04:23 PM.

[metro1275]

If I remember correctly... the 649 was originally designed for 998's

So it'll behave like a fast road cam, A bit tamer than a 286 though.

Bear in mind you might need to change oil pump too depending on the drive.

P.S.> it's spelt leyland

thanks, didnt know it was the leyland as in british leyland i just saw it soemwhere spelt like that

[Retro_10s]

Cool, anyone on here got experience of this cam????!

[mini13]

The 649 is a FULL RACE camshaft, considerably less drivable than a 286, will be lumpy to about 3k and top out around 7500-8000 (depending on engine). the duration is around 300 degrees on this cam.

[miniboo]

I think sqweaka used to have one in hois 998 with a 1275 head on it and a weber 40. hr said it didn't come on cam till about 4000 rpm and revved to about 10000!!!!!!!!!!!!!!!!

[mambaman]

mini13 is correct although i have heard of other designs somehow using the same name but with completely different figures, must be said these are all ownbrand 649 cams such as the MED649. Cant be confused with the original pig of a cam that is the 649.

For general information its a medium lift long duration cam, im sure it was originally designed to run with higher ratio rockers aswell. A popular choice in the old days to go with the short stroke motors.

[Retro_10s]

I was just readin about them in a few books I went to dig out... I've found spec sheets saying the cam doesn't come out to play till around 3500-4000, and then readouts saying it comes on at about 2-2500

interesting stuff, suppose it depends on your engine health and spec really.

[mini13]

twas originally designed for the formula juniors in the 60's i belive, which i think were small bore.

[Retro_10s]

yes it was desinged for thou's

[DYO776C]

yes it was desinged for thou's

I can give you some info.....I used this cam with every engine I built in the mid '60s when I was racing Cooper Ss. I also used one in my road car at the time (DYO776C).

The numbering is somewhat confusing, as the part number was C-AEG648 from BL Special Tuning, but it was universally known as a 649.

The actual driveability depends on a number of factors: engine displacement, cylinder head chamber design, and exhaust manifold/silencer system, carburation and last but not least Final Drive ratio together with wheel size.

In my own case, my racers and road car shared the following: genuine S block with fully worked (Blydenstein) genuine S head including Nimonic 80 sodium filled exhaust valves, BL ST LCB 2" exhaust manifold, 45DCOE Weber with 5" manifold, BL ST SCCR gearbox. The racers used FD of 4.1 with LSD, road car with 3.939. The racers had single box ST BL high flow exhaust, with the road car using twin box system. All cars used 10" wheels. All cars also ran with 11.5 CR (probably not possible today).

The racers (1293cc) would provide poor erratic idling, with power from 3500 ~ 7500 rpm, the road car (1340cc) from 3000 ~ 6800 rpm, with slightly improved idling.

A friend of mine had a 970S overbored to 999cc and with this engine, lousy idling (really) and power from 4000 ~ 8600 rpm. So engine volume has a very marked influence.

The car I currently have has a similar spec to my old cars, but with 1380cc, 45DCOE 276 cam (Piper), twin box LCB 2" exhaust, 3.2 FD with Quaife and 12" wheels.

To be brutally honest, this car is no fun to me. The cam is just TOO tame. A lot depends on what you are used to, how you drive, and the type of roads you use.

I'm looking for a genuine BL ST 649 myself, so I can get back the performance I was used to with the old cars, and yes probably a different FD (maybe a compromise 3.44 or even 3.765 - I tend to use my other car - a Volvo V70 T5R - if I am intending to use motorways/long drives), but I'm seriously thinking of going back to 3.939.

Last comment: a combination of properly worked head, 45DCOE and 649 can provide a truly emotional experience, the note from the carb/exhaust changes dramatically as soon as the engine comes on cam, together with smooth incredible power. On cam, the intake/exhaust noise becomes MUCH less - a very erie experience.

If you can live with the car being a real handful in traffic, then go for it (assuming everything else is done properly). Just don't consider it if the rest of the engine is so-so.

[metro1275]

[quote name='DYO776C' post='360859' date='Oct 13 2006, 12:14 PM'][quote name=
If you can live with the car being a real handful in traffic, then go for it (assuming everything else is done properly). Just don't consider it if the rest of the engine is so-so.[/quote]


thanks again for this advice i dont think i will go for it yet as i havent got a modded head (yet) and im still running 1 carb and 12 inch wheels