Rootes R20 camshaft picture

This was IMPorted for the race Imp built up here in Cape Town over 2011/12 then exported to Scotland, where it came from originally of course!

The suppliers also sent the new tappet buckets and camshaft bearing set.

Setting the R20 camshaft up on a 998cc Imp Sport 180 series cylinder head, the timing is being set, note the dial gauge.

Set the lift on number one inlet valve to 0.113" of an inch with the number one piston
on TDC. Check the series of holes in the drive sprocket, this was Rootes Competions answer to easier camshaft timing over the Imps standard sprocket single hole.

Note the TDC on the steel pointer ( top dead center )

Roy

JoLon Imp to drive across Africa

Terence Tracey will soon be driving his specially prepared Hillman Imp all the way from Johannesburg, South Africa to London, England!

JoLon Imp 2013 fundraising dinner; 14th January @ Scrooge Diner Brightwater Commons 19h00.

 

The fund raiser was a great success, more donations will be most welcome and 15% of all funds raised do go to selected charities.

 

https://www.facebook.com/JoLonImp

Roy

Terence Tracey races his Imp in South Africa

Well he does but this time he loaned his Imp to a friend who just managed to lap the same circuit some 9 seconds faster!

now treat yourself to superb historic car racing from Kyalami race track where my tiny Hillman mixes it with some meaningful big machinery! My Imp has only 930cc engine but the secret weapon this time around id the driver, and since it is boxing well above its weight you can be sure it not me at the wheel but a much better driver; Wayne Berrington-Smith son of the ex Ecosse and Alfa racer from Maritzburg of the '60's and 70's.

Roy

Imp 998cc piston picture

Seen here it looks perfectly round but pistons are not round!

The piston size increase from the normal 875cc to the 998cc size requires the piston to be made 14.1% thats then 998.37cc
close enough for the purpose of this thread. This piston was made in Australia but they are made in other countries also.

Have a look at the way the Imps bearing cap is grooved to meet the conrod, there is no room for movement with this design.

The cylinder head behind the piston is an early Mk1 version, casting
 number 7010128 C

The piston diameter is 71.89mm across the pin and 72.38mm across the thrust face, the 998cc Imp block is said to have a bore of 72.5mm.

Roy

Camshafts, the early Imp ones

Lots of discussion on the various Sport and competition camshafts exist, the Sport 310 lift, the R17 and R20 with a 360 lift come to mind but what about the original 1963 camshafts?

Having just rebuilt a very early Mk1 Imp engine, number B41 / 1/ 501572 I find that the camshaft it came with is not as early as the one on another early Imp head I have.

This is cam casting 7010141 and after running the rebuilt engine for a number of hours.

More casting numbers, what does 2350 mean?

The letters MC, meaning what?

I set this early Mk1 head up with the camshaft the engine came with, only to find that the Mk1 head set up just some weeks before had camshaft number 7010000, was this the very first issue?

Note the original Solex carb with the auto choke fitting, its under the black cap. Brian Baylis has posted me the two missing copper pipes and from New Zealand, many thanks Brian!

The engine is a static display, at this time I have no car to fit it into.

Roy