[denty802]

had a bit of a search and couldnt really find much,
has anyone bored out the 1.3s?
is it worth it?
i've got a spare one here i was thinking of rebuilding for a bit of fun and learning, thought boring out might be a option of better power?

let us know your thoughts everyone

[stocker]

(go for a efi 1.6 they are way more fun and will give you stacks and heaps more power

[joe5701]

denty802 wrote:

had a bit of a search and couldnt really find much,
has anyone bored out the 1.3s?
is it worth it?
i've got a spare one here i was thinking of rebuilding for a bit of fun and learning, thought boring out might be a option of better power?

let us know your thoughts everyone

mate usually you would bore a cylinder to take any marks and imperfections out not to gain power in saying that with strokers and such its a combination of oversize bore and stroke usually.
you would have to take it out a long way to get any noticable gains, and then you will be splitting bores an such because it takes a lot of material out between oil gallerys and water jackets.
if its just for experience and the bores arnt bad give it a good hone and go from there.

[denty802]

yeah thats sorta what i was thinking

im constantly on the lookout for a 1.6 near me haha

[harvs]

Taking it out 1mm, which is about all that is normal (i.e. pistons are commonly available and you're not likely to crack blocks etc.). You're going to end up with a increase of 2.7% in capacity. That's not about to rock your world, and in my opinion, definatly not worth the money.

[monley]

My mate bored his old 1.3 LT out to 1.5LT with other stuff done to the motor (can't remember what he did to it now), but it went like the clappers with 30x9.5's and stock gearing.

[joe5701]

monkey wrote:

My mate bored his old 1.3 LT out to 1.5LT with other stuff done to the motor (can't remember what he did to it now), but it went like the clappers with 30x9.5's and stock gearing.

I could be wrong but to take a 1.3 to 1.5 thats alot for just boring thats more like boring and re-sleaving. I dont know what the bore and stoke of a 1.3is but 200cc is alot

[joe5701]

harvs wrote:

Taking it out 1mm, which is about all that is normal (i.e. pistons are commonly available and you're not likely to crack blocks etc.). You're going to end up with a increase of 2.7% in capacity. That's not about to rock your world, and in my opinion, definatly not worth the money.

1.335cc

[harvs]

STD 74mm bore & 75.5mm stroke for the G13B (i've just assumed that's what we're talking about..)

so std we're talking 1298cc

1mm over 1334cc

2mm over 1370cc (still quite possible, though probably with reduced life)

5mm over 1480cc

6mm over 1518cc

So yeah maybe with an off set crank grind (i.e. stroke it), custom rods & pistons + 2mm over you might get to 1.5L. Would seem totally rediculous when you could just replace it with a G16 though.

[nato78]

I'm currently rebuilding a g13a to swap into my Sierra, I'm boring it out to 1mm oversize, plus the g13a is a slightly bigger capacity to start with, 1324cc as opposed to 1298 for the g13ba.

[zooky08]

1mm is 40 thou I'm pretty sure.
My g16a in my seirra was bored out to 1mm oversize.
It went much better after that, I wouldn't go more then 1mm though IMHO

[joe5701]

zooky08 wrote:

1mm is 40 thou I'm pretty sure.
My g16a in my seirra was bored out to 1mm oversize.
It went much better after that, I wouldn't go more then 1mm though IMHO

usually an engine does go much better after a rebuild, I'd say it was more the freshen up than the cc's

[zooky08]

joe5701 wrote:

zooky08 wrote:

1mm is 40 thou I'm pretty sure.
My g16a in my seirra was bored out to 1mm oversize.
It went much better after that, I wouldn't go more then 1mm though IMHO

usually an engine does go much better after a rebuild, I'd say it was more the freshen up than the cc's

Yea I would agree. If u after power I would waste time boring out unless your bores are oval or marked

[Jester]

Im pretty sure there are pistons easily available for .5mm increments, cos im running .5 oversize since my rebuild only for the reason needed to clean bores up properly not for any gains, though im talking 1.6 here

[nato78]

Jester wrote:

Im pretty sure there are pistons easily available for .5mm increments, cos im running .5 oversize since my rebuild only for the reason needed to clean bores up properly not for any gains, though im talking 1.6 here

That's the same reason I went 1mm oversize, had to clean up the bores with a rebore and hone, so I thought why not go the extra 0.5 and take it up to 1mm over, can't hurt the performance even if the gains are only minimal, and it didn't cost any extra to do it

[dank]

I reckon you would be better off mucking around with trying a high compression 1.3 and run it on premium. still a lot of buggerising around. If I was you I would rebuild it to stock and then sell it to fund a G16 project.

[Kermy87]

dank wrote:

I reckon you would be better off mucking around with trying a high compression 1.3 and run it on premium. still a lot of buggerising around. If I was you I would rebuild it to stock and then sell it to fund a G16 project.

I built a high compression g13a a few years back, bored 1.5 mm, flat top pistons, chrome piston rings, shaved head and I'm pretty sure a stage 2
Cam, went like a cut cat for a 1.3 carby , reved out to 7900 and started valve bouncing

[skyman]

I had one with H/C pistons too. It was a go-er that is for sure.

[SuziBlu]

Kermy87 wrote:

dank wrote:

I reckon you would be better off mucking around with trying a high compression 1.3 and run it on premium. still a lot of buggerising around. If I was you I would rebuild it to stock and then sell it to fund a G16 project.

I built a high compression g13a a few years back, bored 1.5 mm, flat top pistons, chrome piston rings, shaved head and I'm pretty sure a stage 2
Cam, went like a cut cat for a 1.3 carby , reved out to 7900 and started valve bouncing

7900 is valve bounce revs, cool. I often take my lil donk up to 7k, an it is still pulling well, but afraid to open her right up, now I know. So i have some spare, excellent.