4-Star
Author
Discussion

bobthemonkey

Original Poster:

4,122 posts

233 months

Thursday 19th April 2007
quotequote all
Not exactly car related, but it does involve engines.

I've got an old 4-stroke Fiat engine (on a lawnmower) which is meant to tun on 4-star. I can't seem to get LRP anymore, os have been (apprehinsivly) running it on unleaded.

Should I start adding some kind of additive (Millers VSP?) or for such a worthless thing just keep with the unleaded and hope for the best.

wildoliver

9,170 posts

233 months

Thursday 19th April 2007
quotequote all
is it an alloy head? if so it will most likely have seats that are perfectly hard enough anyway.

Even if it has a cast iron head I have not sen any evidence of valve seat recession in any cars I have worked on, mainly old british stuff, it all seems to be a bit of a myth, I do however come across a lot of engines that have problems mainly headgaskets and pistons burnt out that have religiously used Lead replacement additives.

Nothing conclusive I know but I don't use them in my motorsport engines, or road engines and they do big mileage and get used damned hard with no problems whatsover.

bobthemonkey

Original Poster:

4,122 posts

233 months

Thursday 19th April 2007
quotequote all
Thanks, I think I'll just cross my fingers and hope for the best.

wildoliver

9,170 posts

233 months

Friday 20th April 2007
quotequote all
To be honest I'd be surprised if you ever noticed the difference.

I'd use super unleaded though to keep the octane up around where it should be.