44 replies to this topic

[WiredbyWilson]

Hi all,

I have bought a complete 1275 engine and am planning to build a failry tuned 1293, 1310 or 1340 and have a few questions.

1. Which is the better option to take 1293 / 1310 or 1340?
2. With each option what would be good pistons to use without having to sell my legs?

Cheers Guys & Gals

Wilson

[Ethel]

There's no substitute for cc's (short of a turbocharger)

1330 - no need to go OTT on pistons if it's for the

road http://www.minispare....aspx?pid=34973

Think about CR before you spend any money.

[mini_lad_1990]

that has helped me alot thanks mate i am looking at doing the same and was worried about the price of the pistons as i was eyeing up some omegas?? would the omegas be better for performance or will it be about the same as the minispares one??

cheers

[WiredbyWilson]

Sorry to sound like a proper simple-simon (no offence to anyone called simon) but what would be a good compression ratio for a road going 1330 with a morspeed cam and a weber 40 fuelling it?

Cheers

[mini_lad_1990]

also i might sound like a complete and utter noob but do they class a 1330 as a 1340??

cheers

[Ethel]

Standard rebore sizes are 20,40,60thou giving 1293,1312,1330 cc's

I know you can get +80 pistons for 998's not sure abut 1275's, but you can get 1380 with 73.5mm pistons.

CR depends on the fuel you burn mostly.

Pistons are about surviving high revs more than anything. Good design may get a little more power by reducing friction losses.

[mini_lad_1990]

i was going to go to the 1380 bore but im thinkin of reliabilty will the 1330 be better than the 1380?? or is that just a myth??

i seen a few minis with the 1380 lump producing 100bhp at the wheel is there any way of getting that out of a 1330 or that a big NO NO? lol

which do you guys advise me to go for i want to be in the 13's so im looking at either the 1330 or the 1380??

cheers

[1340 gt]

a honest 100bhp isn't that easy to acheive but can be done with a 1275 without shocking expense so can be done with 1330, 1340 or 1380.

imo 1380 is the last sensible rebore so if you go that far you wont be able to take it any further in future. if i were you i'd get an engineering company to check the bores and tell you what bore the block needs taking to and do the minimum.

[T.Harper]

a honest 100bhp isn't that easy to acheive but can be done with a 1275 without shocking expense so can be done with 1330, 1340 or 1380.

imo 1380 is the last sensible rebore so if you go that far you wont be able to take it any further in future. if i were you i'd get an engineering company to check the bores and tell you what bore the block needs taking to and do the minimum.

hear heyaaaarr!

Gives you the possibility of rebores for the future

[Ethel]

It's becoming a tougher call, but in all honesty how many A Series get even 1 rebore to extend their lives rather than as performance tuning? For the price of new pistons you can still just about find a replacement block. I'd go for a 1330 for a N/A engine over a 1293 or 1312 because it will cost you the same. A 1380 will cost a bit more so you have to decide if the extra performance is worth paying for, both in cash and the few reliability concerns - head gaskets.

[mini_lad_1990]

i am heading down the 1330 road atm haha!!

i was wondering if anyone has a average price for the re boring the block to the 1330?? i found some pistons for it yesterday and i was wondering what they are like??piston

cheers

[Bristolboy]

how do you get a 1405 then?? because i'm sure iv'e seen one on here.


Bb

[Ethel]

You used to get 74mm pistons but not straight forward to use. You can also squeeze out a few more CC's by regrinding the crank off centre.

[RobG295]

i am heading down the 1330 road atm haha!!

i was wondering if anyone has a average price for the re boring the block to the 1330?? i found some pistons for it yesterday and i was wondering what they are like??piston

cheers

I'm looking at doing this at the minute as well. I rang a couple of companies and the best price i found so far was from southam mini & metro centre, which was £80 + vat. Seemed very reasonable to me.

[alexcrosse]

out of interest, i thought if you rebore to 1330, you cannot then offset to 1380 afterwards...