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anyone bored out a 1.8 to a 2.0ltr?

thinking specifically of the NB8A...

anyone done it?
what kinda pro's and cpon's are there?
costs?
power?

...im looking for some not-too-expensive mods to do to begin with, that can be added on later... (eg. cam, computer, turbo...)

don't think it's possible by boring alone, would have to be bored & stroker kit with a reground crank or the famous billet crank from Flyin' Miata. extremely expensive, looking for cheap look elsewhere..

Max overbore gets you to 1930cc or therabouts. Will definitely need to be stroked but there is nothing cheap about it - factor in about $5k just for getting the FM stroker kit here, let alone fitting it and doing the rest of the motor.

Boring is probably one of the more expensive mods you can do due to the labour and the new parts needed.

Anyone here consider swapping the engine to SR20DET. I know a guy in Perth did it, and plenty in US. I wonder how much the cost will be here?

I used to have S14, and to get over 200RWKW from the stock engine is quite easy.

thanks guys!

my mate had an older car bored out a while back, didnt cost that much.. a lot simpler engine tho i guess.

...i thought it would be a good start to set up a car for later heavier mods (turbo etc)...

it seems you cant get much noticable power boost for under $3000 hey.

My clubman had its block bored out so its now a 1.9L....(well 1.88 to be better put ). Total cost, including blueprinting the block and balancing the crank was about a thousand, however you will then need to factor in the oversized pistons, and labour to completely tear down the engine. Its the sort of thing, that if you're gonna pull the engine apart to do it, then u may aswel do cams, cam gears, solid lifters, IRTBs and ECU all at the same time, since you'll have the engine in pieces

Umm.... there is atleast 1 mx5 i know of driving around with over 200rwkw on a stock engine... so why do you need to bore ?

Tick4d,
Speedworks fitting kit is $1650 inc GST for the mounts alone. Then you need to modify the sump. Their kit with sump is $3850 inc gst.
Can you send me what you know as I am in the process of getting the bits together to put an SR20det in my clubman and while it is not hard it is definately not easy.
The big part is the expense if you want to do it legally.
Jake

Marador wrote:Umm.... there is atleast 1 mx5 i know of driving around with over 200rwkw on a stock engine... so why do you need to bore ?

Is that with forced induction, or is it still NA? Surely FI?

200 wkW would have to be FI imo
The big problem with increasing displacement is that the motor life is dramatically reduced. Sort of catch 22

1930 cc if you just bore but we've made 1983 cc when combined with head work.

Btw, if anyone has their motor apart and wants to make power easily, match port the inlet manifold.

When Mazda brought the 1.8lt motors into the range there is a rumour that they made to much power for Aus regs, so they detuned them by under sizing the inlet manifold. We have just taken 300 grams of metal out of the inlet manifold just to match the stock gasket (still more to go)

Wòó

AB7 wrote:
I used to have S14, and to get over 200RWKW from the stock engine is quite easy.

I wouldn't use the figure "200RWKW" and "stock" in the same sentence. That's gotta be over 350HP at the fly .... and that number seems well above the capacity of the G25.

Just how easy is it on a stock engine to get 200RWKW?

Techno wrote:

AB7 wrote:
I used to have S14, and to get over 200RWKW from the stock engine is quite easy.

I wouldn't use the figure "200RWKW" and "stock" in the same sentence. That's gotta be over 350HP at the fly .... and that number seems well above the capacity of the G25.

Just how easy is it on a stock engine to get 200RWKW?

Depends... If you just want to stab 200kw on teh dyno, then drive it daily you wont have an issue on s tock engine, it has been done by at least 2 forum members, but if you want to have 200kw and use all 200kw regularly you are not going to be keeping stock engines long.

Woo wrote:1930 cc if you just bore but we've made 1983 cc when combined with head work.
Wòó

How do you expect to increase the capacity through headwork?
The capacity is calculated from the bore and stroke and is independant of compression ratios etc