Is it possible to put a 1300 head on a 1200 lump any gains?

[D7AKE]

As subject really

thanks Simon :wink:

[mowgli]

Yes & no...... just mmake sure you use the 1.2 head gasket cos they are bigger bore.

Now if you stuck a 1300 crank in a 1200 block with 1300 rods & 1200 pistons then you'd have some power gains, & a high compression 1400

[Stuart]

in the 1.2-1.4 range the 1.2 has the best flowed head as std. so theres no point in swapping. as for the crank and rods change im not sure if the pistons will poke out of rht etop of the block, but if it does work you will have 4cc more than the proper 1.4's lol

[mowgli]

the conversion does work, I did it back in 1992 and it made a very good road engine, although I did have to have a small amount of metal removed from the piston dish to get the compression down to about 10.5:1, but it was quick, reliable, and all of the outer bits needed no modification at all. if you have a 1200 or a 1300 and don't have a very big budget, it works out quite well.
By the way, the engine is now in an astramax and still going strong.

Cheers

[jon_boy]

so mowgli what bitsa from each engine (1.2, 1.3, 1.4) do i need? im looking to make a half decent engine on a bit of a budget for the time being and this sounds good.

[mowgli]

The easiest way is to get a 1300 rebored, then fit new 1200 pistons which need the compression ratio altering.
PMC used to do a kit, and they might still be able to help, I used a copy of the Vizard Mini tuning book as a reference guide, did the sums and had a friendly engineer machine them down. He was so worried about the job that he wouldn't charge me for doing it in case I sued him if it blew up.
You can fit either a 1200 or a 1300 head, but use a 1200 gasket.

When I did it, I fitted a new oil pump, had the head & crank checked, fitted new bearings, seals etc & put it together on my bedroom floor. Unless you have strong friends, I would advise you do the build downstairs. It ran on the std 1200 carb, but with the std 1300 exhaust. I couldn't afford to swap the gearbox, so it ran a std 1200 merit 4 spd. The clock would show some very interesting speeds, & 0-60 was around 10 seconds. I can't be any more accurate than that, or the max power lot will get hot under the collar.

Hope this is some help