Cameron Greig writes: =
>Hi All
>I am in the UK, and yesterday went to look at a rather nice TR250 that
>had recently been shipped from California.The car is in mess,but
>structurally solid,and complete.After getting home I started reading up
>on the 250 and was surprised to find that the standard 250 only produces=
>104 bhp,as a posed to 150 from the TR5. I knew the 250 was detuned but I=
>had not realised by how much.Apart from the obvious difference of fuel
>injection / carbs what other differences are there? I was thinking mainl=
y
>about the camshaft,and gear ratios.
> Finally what have any of you TR250 owners done to your cars to increase=
>the performance.
>Thanks for any comments
>Cameron.
Cameron,
As you mentioned, the fuel delivery is different and the camshaft is
different. Additionally, I think the compression ratio is lower on the
250.
Another difference is the measurement standard. I believe the
measurement technique used in each case is different which inflates
the 150 BHP rating somewhat. I read somewhere (I forget where) that
if the early TR5's and TR6's were measured using the US standard the
rating would be closer to 135 BHP. Something to do with whether or not
the exhaust is fitted or the belt driven accessories, etc.
As far as re-finding all the lost horsepower, Kas Kastner published
a competition manual. I have a copy and it is a what-to rather than
a how-to book. In other words it tells a good machinist what to do
expecting that he already knows how to do it. Recomended reading.
Dave (don't feel too bad, we colonists have been putting up with
these detuned cars for 20 years and we still love them) Massey
|