5 replies to this topic

[l7jnd]

Sounds daft, you'd think I know but please read on:

having only had standard engines previously I have no knowledgeof what difference an uprated cam would make to genreral driving.

I have been given a 1275 engine with what the previous owner told me is a performance camshaft - didnt tell me what type and I'm not sure if he was just having me on, the engine was free so I just accepted what he said.

I now have the engine fitted and running after finding a carb to suit and sorting out the wiring for the different starter etc

It runs a little lumpy but i have not set mixture or checked timing yet, just happy to hear it run!!

Question is - can i tell without stripping it all down whether or not it has an uprated cam, does it drive or idle differently? Is there any way of telling ?

If I did strip it down, what would I be looking for on the cam, would it be stamped with something?

The engine has been apart before, there is blue sealant on the timing cover and the gearbox is a gold seal item.

Any thoughts or ideas will be welcomed.

Cheers
Jim.

[crazycoleman118]

if you strip it down on the end of the cam you'll be able to see some marks stamped into it, onces its set up though you should feel it has power normally between certain rpm's dependant on cam.

[Cerberus]

You could try to identify it by measuring the cam lift using a dial gauge on the piston, and measuring the duration.
Its not brilliantly accurate, but we managed to narrow down what cam we had in our crossflow down to 3 choices. And when the engine was finally stripped, it was one of these three.

[andymini12]

If it does have a cam in, it will be lumpy on tickover if a fast road or above.

[jaydee]

Never checked without taking the camshaft off, but being yours a 1275 with no tappet chest (if it had it was one of the rare and expensive 'S' blocks!) i can understand why you're asking.

The only way to really make sure of what cam is in your engine is to be get hold on a crank protractor and a degree wheel, remove rad and timing cover, and measure the cam timings.

Alternatively, you can make an educated guess this way:
Just measure the lift on both valves with cylinder one TDC at overlap.
If it is about 1mm, then it is a BMC leyland standard cam if its more than its an uprated..i wont be measuring maximum lift because some upgraded BMC cams retain standard maximum lift.

[l7jnd]

Hey Guys, thanks very much for your replies, I think I'll give jaydees educated guess method a go at the weekend and see how that works out.

Thanks for your help.

Jim.