37 replies to this topic

[Elmomini]

what should i offset bore my 998 engine to to keep it cheapest and what else would i need to do it

[travellering]

Why would you need to "offset" bore your 998? This is usually only done on large bore motors as the walls between the cylinders get too thin to stay inline with the bores. I haven't heard of many piston choices available for a 998 that would allow enough of an overbore to necessitate offset boring...

[Sam Walters]

Why would you need to "offset" bore your 998? This is usually only done on large bore motors as the walls between the cylinders get too thin to stay inline with the bores. I haven't heard of many piston choices available for a 998 that would allow enough of an overbore to necessitate offset boring...

I havnt heard of any! Knock a set of +120 in there and be done with it

Edited by Sam Walters, 07 June 2011 - 09:03 PM.

[Elmomini]

Why would you need to "offset" bore your 998? This is usually only done on large bore motors as the walls between the cylinders get too thin to stay inline with the bores. I haven't heard of many piston choices available for a 998 that would allow enough of an overbore to necessitate offset boring...

can i not offset bore it to 1380

Edited by Elmomini, 07 June 2011 - 09:04 PM.

[Stevee]

Why would you need to "offset" bore your 998? This is usually only done on large bore motors as the walls between the cylinders get too thin to stay inline with the bores. I haven't heard of many piston choices available for a 998 that would allow enough of an overbore to necessitate offset boring...

can i not offset bore it to 1380

1380 you will gain from a 1275 not a 998 unless you bore it up and have a custom crank made up :/ but thats major money

[Elmomini]

Why would you need to "offset" bore your 998? This is usually only done on large bore motors as the walls between the cylinders get too thin to stay inline with the bores. I haven't heard of many piston choices available for a 998 that would allow enough of an overbore to necessitate offset boring...

can i not offset bore it to 1380

1380 you will gain from a 1275 not a 998 unless you bore it up and have a custom crank made up :/ but thats major money

what should i do to my 998 as in bore wise

[charie t]

put a 1275 in

[valve bounce]

but david vizzards tuning the a serise book, read it cover to cover. that is the best thing to do if you want to do much with mini engines.
on a 998 +80 with minispares flat top pistons is a good mod this brings the cc to 1062, throw in a sporty cam and an uprated head and youve got something that'll keep up with standard 1275's

[minilee94]

im going to be keeping my eye out on some of there replys as im building a fast road 998 iv already got a fast road cam and duplex chain and gears

[Elmomini]

but david vizzards tuning the a serise book, read it cover to cover. that is the best thing to do if you want to do much with mini engines.
on a 998 +80 with minispares flat top pistons is a good mod this brings the cc to 1062, throw in a sporty cam and an uprated head and youve got something that'll keep up with standard 1275's

my dad told me about that book looks like i will have to get it
is 1062 the most you can get

[valve bounce]

i think you can get +120 pistons but there not readily availble in this country, these take it to 1090? i think

[Elmomini]

i think you can get +120 pistons but there not readily availble in this country, these take it to 1090? i think

ok thanks does the book tell you about what to do with cranks and what rockers and cams to use

[bmcecosse]

Don't waste time and money overboring a 998. Either use it as it is - or get a 1275.....

[minilee94]

yh but like he got proved he cant overbore a 998 so there nothing wrong with him making a fast road 998cc or sumink just depends what u want

[Elmomini]

yh but like he got proved he cant overbore a 998 so there nothing wrong with him making a fast road 998cc or sumink just depends what u want

all i want is to get the most out of the 998 to make it a fast road