I am building a locost using a sierra donor and am just about to start building the chassis. i will build it as a +4 chassis to fit the sierra track, but am worried about the height of my engine as it is very tall. should i build the chassis the same height as the book and put a large bonnet on or adjust the height of my chassis?

what about the+442.

2 inches taller.
thats what i am buliding, using a sierra

I didnt find my cvh very tall, if you shorten the sump, you can lower the engine a bit. mine fitted fine using GTS standard bodywork, with no holes or bulges. the carb was a pretty tight fit, but there was enough space foe a custom made filter.
if you need any cvh bits, i have a complete engine spare, and any bits are free to good home. the engine itself is pretty dead, but all the anciliries are there.

New belts, fuel pump, alternator bracket,plugs and leads etc....

Tom

Shorten the sump and cut the raised part off the cam cover, mine is standard book dimensions.

Used to have a Caterham bonnet bulge for the downdraught carb but dont need any , for the bike carbs..
Rescued attachment my profile sml.jpg

I've put a CVH in my Indy - and it fits fine. I have had to shorten the sump and move the alternator. The air filter will need a hole in the bonnet, but that's fairly standard.

Good luck

Stu

cheers for the help