Engine info

[Beachie]

OK, 'nother Q.

My TR6 for some reason was fitted with an engine and gearbox from a 2.5PI saloon producing what I believe to be 132 bhp. I am led to believe that the only difference between this engine and the original 150bhp is the camshaft. Can someone shed any more light on this please? Are there any differences between the metering units? I aim to use a camshaft for a 150bhp engine anyway.

I want to try to achieve a true 150bhp rather than the estimated for the time which actually turned out to be more like 140bhp. Can this be achieve by using tubular manifolds rather than the original cast ones and then matching ports from the head to the manifold or would I need to do a little more? I am not after a fire breathing monster as that is not what these cars are about, but I would like to unleash a little more of the potential power that the engine will have hidden away. The car came with a stainless sports exhaust system but I have no idea the quality or the condition.

[Nick Jones]

Depends what age of PI saloon. The Mk1s and Mk2s up to approx 1972 had 132 bhp (ish) and the later ones (engine no. > MG 750000 IIRC) had 125 bhp and used the same cam as the "CR" TR6.

 

The cam is the only internal difference. The MU will be calibrated differently though.

 

To get a true 150 will take some head work. The right 6-3-1 tubular manifold might help although the standard twin-down-pipe cast one is really pretty good. Getting it all set up by someone who knows how to tweak the MU and not relying on bench set-up is important for best results.

 

Nick

[Beachie]

Seems like I am on the right track then, so ahead with the plans in my minds eye. The metering unit I will replace altogether as the existing one is in a very sorry state and obviously not correct for the original spec for what should be in there.

[Denis]

Beachie, What's the year of your car? If it's not the original engine number,...perhaps it's a correct replacment for a later CR designated TR that has the lower profile cam, producing 125bhp?

[Beachie]

The year of the car is 1972 but the engine and gearbox with the overdrive, which I believe to be a J type (whatever that is...) is out of a 2500 PI saloon. In the paperwork, of which there is plenty there is a note that to replace the clutch I need to order the same parts that fit the saloon car and not the 6.

The chassis number is a CP.

[RobinTR6]

The shaft from gearbox to engine is smaller than the TR6, you only need to get the clutch plate for the saloon, or GT6, not sure but its not a problem. It has smaller hole in middle.