Hi All.
When fitting the P75 TB to a cinq, do you need the alloy spacer as the TB(off ebay) I've ordered dose not come with one. Or can i modify the OE(1108 SPI).

Thanks for reading.

I think you should beable to bore out the standard cinq one, Ive done em to 40mm no trouble.

lets get to work with the dreemel!!! cheers david.

Presumably the head is being gas flowed and a more sporty cam is going in. Just opening up the TB on its own wont do much.

Whitesie. Cam fitted, Chip fitted just now modding my P75 TB. Then P75 exhaust mani, head being done MrFixIt after that, then back box( dont think much point in centre sect' at the mooment only aiming for 75BHP) oh and some 8.5 mm HT's and a Focus Induct' kit modded with BMC CDA filter.
Happy days!!! should just about squeeze 75 little raging ponies!!!! bring on the boys with there stick on Halford parts, Oh **** forgot they have neon's!!!!!!

ps. not 100% about head work, may just fit P75 head with SPI mani(has already been done and proven!!)

Sounds good. Go for the 75 head with some gas flowing breathed on cam and flowed 75 TB.

A long time ago, I ported a Mini A-Series 1275 even with standard cam it revved like ****. I had a gas flowed 1.5" SU which needed a better inlet manifold but it was still enough to surprise bigger stuff. I used David Vizards "How to modify your Mini". Still very relevant today.

Back then Vizard was getting 110 to 120bhp from the 1275 running twin SUs. but that was a race engine with special crank rods and pistons and a very hot cam. The biggest drawback was the crappy 4 speed box.

Whitsei cheers for your comments. What does "breathed on cam" mean? heve'nt heard that term before.

P75 head. So fitting this head will be an improvement. Will get skimmed to the max, port inlet and clean but not polish. Exhaust ports will be cleaned and highly polished but not ported. Will also match mani's to gaskets. Obvisouly the 1108 inlet mani top bolts/studs will no line up so will get a plate fabricated.

Jjust wondering will it be OK to skim to the max when fitting with the 1108 bottom end and what head gaskets shall I use 1242 8v MPI or????

Once this is all done will be running the following 38mm(p75) modified TB, P75 head with SPI mani(inc the P75 cam) induction kit, P75 Exhaust mani and mckirh(always forget how this is spelt) chip, will this chip be suitable with above or will i have to have a custom map. Obvisouly that head is going to change alot of factors.

p.s. Whitesei hows your car and what you running, have'nt had time to go through all your posts.

It might be a bit old hat these days. Its slang for worked over to make a more powerful engine. Its been breathed (on a bit) by the devil. :devil:

These days they say the ports should be smooth but not polished. The gas molecules at the surface are not moving so the gas stream must shear as it meets the metal. A mirror finish causes that boundary layer to be narrower so the shear is more severe. Smooth gives a wider layer than polished and so a better flow.

Obviously ports must be matched to avoid steps - especially bigger to smaller.

I cant say about skimming. You will need to know the bowl capacity. To do it accurately put a sheet of glass with a drilled hole onto the head face with vaseline seal. Use a pipette to measure the bowl capacity. But this only works when all valves and seats are cut identically. On a road engine its all but impossible.

When skinning for power you need to know the least bowl capacity to decide how far to skim. You still risk pre-ignition (knock pinking detonation). Without a knock sensor you need to be very careful.

I'm running a Punto HGT. Its pretty standard apart from cat back exhaust. I have plans for it but currently no time but handily no cash to do the mods.

Two of the best car & engine and tuning books are the A series and Mini books by David Vizard. The stuff he covers is just as relevant today as when tuned Minis were all the rage.

http://www.abebooks.co.uk/servlet/B...=an=david+vizard&bt.x=58&bt.y=9&sts=t&tn=Mini

http://www.abebooks.co.uk/servlet/B...=david+vizard&bt.x=0&bt.y=0&sts=t&tn=A+series

Use the 1108 HG. Don't skim past the markers unless you want a wrecked engine if the cam belt breaks.