IT'S BACK!!!!!!

MR_GEMI · Posted: Mon Apr 22, 2002 6:37 pm Post subject: IT'S BACK!!!!!!

greetings all!
well for those of you that dont know, my car has been off the road for a little over 2 weeks now getting a new donk put in it!
it will be picked up from gemispares at around lunch-time tomorrow.
the new motor is a 1600 bored 120'thou (making it 1824cc), flat-top pistons, fully balanced,the head has been ported and polished, heavy duty valve springs, stage 2 cam, just to name a few of the mods. All specs will be added to my gallery entry within a couple of weeks!
wish me luck!!
cheers
kev
_________________

Momo · backyard mechanic Joined: 08 Feb 2002 Posts: 561

Don't leave me here in the farking dark.....how much did all that cost you? did you supply them with parts?? Did you do any of it yourself??? And - oh yeah - GOOD LUCK!!

MR_GEMI · Posted: Mon Apr 22, 2002 7:10 pm Post subject: Re: Well.........

they did all work, they supplied all parts, grand total $2180
i also have to pay for an unexpected inlet manifold swap so that total is subject to change!
the the bottom end cost me $1150
all head work $620
radiator $80
replacement carby $30
labor was $300
_________________

GasGem · backyard mechanic Joined: 05 Nov 2001 Posts: 755

sounds like s fun unit,

It's interesting thou, I know about a G161 bored out and fitted with 1800 + 40thou flat tops complete reco and balance new clutch, HDD valve springs, reco head
all ready needing assembly everthing suplied,
and everyone thinks it $1300 is too high,

cheers
Eggy

Racegem · backyard mechanic Joined: 30 Jan 2002 Posts: 987

...a 1600 bored out 0.120" is only 1702cc. Not trying to be a smartarse, it's just inquisitive. If it's had a longer stroke crank too, what was it from?

Yonnee.

MR_GEMI · Posted: Mon Apr 22, 2002 9:28 pm Post subject: Re: Sorry, but......

fair enough,
i have been told it has a TOTAL capacity of 1824cc, the guy was very vague about the amount it was bored, at one stage i was told the motor was bored 40 thou, then 120, then 200, but i was told by a mechanically minded friend that 120 would be the the most likely figure to reach JUST over 1800cc.
this has always been an issue on this site, no one seems to come up with the same numbers in the end.
either way im not too concerned, it should still fly... i hope...
kev
_________________

Racegem · backyard mechanic Joined: 30 Jan 2002 Posts: 987

Well here's the calculation I used.
82mm bore. STD
75mm stroke. STD
pi times radius squared = area of piston
times height = volume

3.142 X 41 X 41 X 75
------------------------------ X 4 cyl. = 1584cc (std gemini capacity)
1000

add 120 thou bore or 3mm, then you get;

3.142 X 42.5 X 42.5 X 75
----------------------------------- X 4 cyl. = 1702cc
1000

Yonnee.

Gene FJ20DET · Posted: Mon Apr 22, 2002 9:53 pm Post subject: Re: Well.........

u got riped something major!!!!!
gene
_________________

MR_GEMI · Posted: Mon Apr 22, 2002 9:54 pm Post subject: Re: OK

ok, then can u do that calculation again for me with a 200thou bore, will that get anywhere near the mark? i want to know exactly... i was told the pistons were from a g200 and had also been shaved down a bit, if it was to be 1702cc, wouldnt they have used g180 pistons? and shaved them down a tad instead???
just curious...
cheers,
kev
_________________

MR_GEMI · Posted: Mon Apr 22, 2002 10:14 pm Post subject: Re: Well.........

i dont think i did get ripped personally, as many people do i shopped around, i wanted a repairer with credability ie. not a backyard "specialist" (MTA Approved)
one quote from a reputable adelaide performance company was almost $2500 for a stock rebuild, i dont want to know what they would have charged for extra work!!
most of the stock rebuilds were around the same amount for a decent job...
so after many hours on the phone and visiting places and a lot of number crunching i decided to go with gemispares.
if i could build it myself i would have but just dont have the time or the knowledge to perform such a task...
anyway thats my life story for now...
cheers kev
_________________

Gold TX Sleeper · backyard mechanic Joined: 05 Feb 2002 Posts: 509

The quotes i got were similar to yours when i was in the market for a rebuild on my 1600. I ended up coming across a freshly rebuilt G200 for $1150, and i mean rebuilt - new everything from rods, pistons, bearings etc. It also came with a 6 month warranty. The head was also fresh with new valves, timing chain, springs etc.
So your quotes were'nt too bad for someone who couldn't get mates-rates or a back-yard job done. When the sh%t hits the fan, a backyarder wont honour any warranty and deny any fault. Whereas an approved workshop normally wants to keep your business therefore will fix their mistakes till they get it right - which is more often than not first time.
Jasyn...

Racegem · backyard mechanic Joined: 30 Jan 2002 Posts: 987

...wil get you close.
0.200" bore still only get you 1783cc. And by then your getting dangerously close to the water jackets. There's no way without a stoker crank to get that capacity from a G161 block. I wouldn't mind knowing if they've managed to squeeze in an 1800 crank, and if so, what rods did they use.

Yonnee.

MR_GEMI

they are giving me a spec sheet when i get the car, i will let u know all details as soon as!
_________________

Slug · tinkerer Joined: 06 Oct 2001 Posts: 196

It sounds like it is using a "stroker" crank. He said they shaved the pistons down a bit. This is because the G180 crank fits in a G161 but you will need to use the G161 rods, problem is the pistons are still 3.5mm out of the block thus the"shave pistons" story he was told. Other things are the rod bolts now hit the block and the block needs to be ground away to fix this. All in All it gives you an engine with a real BAD rod ratio, and thats not what you want,( ok for a roady but not what I would want to race on) and its easier just to use the G180 block you pulled the crank out of in the first place... Michael

Racegem · backyard mechanic Joined: 30 Jan 2002 Posts: 987

Yeah, I didn't think it was that easy. Otherwise it would have been done a zillion times before! lol