What a great find your channel is. Brings back memories from 40 years ago and my friend racing a grass track Imp and my 875cc converted Deluxe road car. The good old days. Thanks
A friend I and used to rally an 998cc Imp in the early 80's Big valve head,Wills'rings, R17 cam,on twin forties, front radiator,lowered front wishbones etc. We came first in class on the Isle of Wight Rally. Happy Days😊
Great video Andy Just looking at all your videos now I’ll be racing next year against you haha So need to be on my game now , got some great videos Andy 👍
What is the bore and stroke for the 1400cc Imp engine? Curious to know what was the largest displacement ever achieved on an Imp engine and which capacity range was the more production viable for road-going use had the money been available?
@@thehillmanator Older units were awfull , but the new generations are proving reliable. I've been running a c38 91 in my Honda k20 powered lotus for 4 years now. track days and road use ,its been faultless so far. 440bhp @7800 rpm
What a fantastic creation, I love the "Frankenstein" block patches. Since top end is so limited by the head could there be some benefit from more induction length to maximise low/mid torque? Lovely old dyno as well, do you know how old it is?
Andy, back in the day the magazines were reporting >100hp for 998s with the same lift and 1.4" inlet valves. Do you think they were just at the airflow limit and more suck wont get any more air in? Or is there some restriction I haven't thought of?
In the 70s I built a 998 Imp and we saw 98 bhp at the wheels at 9,750 rpm. The guy who tuned it on the Dyno (John Mowatt) said he thought it was producing about 105 bhp at the flywheel. It was very sensitive to ignition timing. The limit for a 998 was reckoned to be 110 bhp unless you fitted a special head that had downdraft inlet ports which would get you to 120 bhp.
I really appreciate this video. Love a Frankenstein engine, good effort. 👍 I’m wondering if the head could be replaced? Like the K1100 A series engine type deal, wouldn’t be much of an imp engine left but cool. Like it.
What a great find your channel is. Brings back memories from 40 years ago and my friend racing a grass track Imp and my 875cc converted Deluxe road car. The good old days. Thanks
Thank you, glad you enjoyed 👍
Always happy to see you modify everything!! Will have to catch up soon! Mart
Very interesting and informative, nice one Andy
I think it was Paul Emery who did such a liner conversion like that back in the 1960`s
Andy Chessman (RIP) made some very nice imp engines we used to run a 998 with an R23 45 webbers evil little machine
Very interesting, intense engineering...
A friend I and used to rally an 998cc Imp in the early 80's
Big valve head,Wills'rings, R17 cam,on twin forties, front radiator,lowered front wishbones etc.
We came first in class on the Isle of Wight Rally. Happy Days😊
Fascinating!
Great video Andy
Just looking at all your videos now I’ll be racing next year against you haha
So need to be on my game now , got some great videos Andy 👍
What is the bore and stroke for the 1400cc Imp engine? Curious to know what was the largest displacement ever achieved on an Imp engine and which capacity range was the more production viable for road-going use had the money been available?
Grande máquina belo motor de competição muito muito bom 👍🚙👍
A nice Rotrex would up the power on this😉
yes am sure, the question would be for how long?
@@thehillmanator Older units were awfull , but the new generations are proving reliable. I've been running a c38 91 in my Honda k20 powered lotus for 4 years now. track days and road use ,its been faultless so far. 440bhp @7800 rpm
What a fantastic creation, I love the "Frankenstein" block patches. Since top end is so limited by the head could there be some benefit from more induction length to maximise low/mid torque? Lovely old dyno as well, do you know how old it is?
Thank you, yes am sure more could be gained lower down the rpm range, not sure how well the crown wheel and pinion will like it 😬
The dyno is 1960’s i think it came from gardener diesel engine factory in manchester, it is my favourite piece of machinery ❤️
Andy, back in the day the magazines were reporting >100hp for 998s with the same lift and 1.4" inlet valves. Do you think they were just at the airflow limit and more suck wont get any more air in? Or is there some restriction I haven't thought of?
In the 70s I built a 998 Imp and we saw 98 bhp at the wheels at 9,750 rpm. The guy who tuned it on the Dyno (John Mowatt) said he thought it was producing about 105 bhp at the flywheel. It was very sensitive to ignition timing. The limit for a 998 was reckoned to be 110 bhp unless you fitted a special head that had downdraft inlet ports which would get you to 120 bhp.
I really appreciate this video. Love a Frankenstein engine, good effort. 👍 I’m wondering if the head could be replaced? Like the K1100 A series engine type deal, wouldn’t be much of an imp engine left but cool. Like it.
i have weighed up many a 16 valve head but can’t find anything with same bore spacing!!
There must be some kind of cross flow head that would fit that don’t give up on that even if it’s 8 valve
Be a nice candidated for a turbo get a bit more air thru it by force
ha ha yes maybe one day !
Sounds like you didn't have it balanced correctly.