View Full Version : 1.2 ohc carb modding
cov_street_racer
06-04-07, 08:49 PM
heya guys, i have a 1.2 carb and i wous woundering could i fit a 1.3 head onto it????? and eventually fit 1.3 cams?????
thanks eddie
Jon_nova1
06-04-07, 10:51 PM
1.2 and 1.3 head are the same
turbojolt
07-04-07, 12:03 AM
i think he must mean the sr head
cov_street_racer
07-04-07, 12:53 AM
i do turbojolt
1.3 and 1.3 "sr" head is the same.....
turbojolt
07-04-07, 06:26 PM
1.3 and 1.3 "sr" head is the same.....
did not know that i must say but the cams must be compleatly diffrent
Cams are the same too.
Nowt special about a 1.3SR engine.
Just a normal 1300cc engine
turbojolt
07-04-07, 06:32 PM
Cams are the same too.
Nowt special about a 1.3SR engine.
Just a normal 1300cc engine
so would 1.4sr cams fit in to it
Yeah, but the dizzy is different so you wont be able use a 1.3 dizzy.
Pointless going from a 1.3 cam to a 1.4 one.
turbojolt
07-04-07, 07:01 PM
Yeah, but the dizzy is different so you wont be able use a 1.3 dizzy.
Pointless going from a 1.3 cam to a 1.4 one.
no dont forget he has a 1.2 mate
Oh sorry, thought you were asking if a 1.4 cam would go in a 1.3.
My post still applies anyway :p
Will need to change dizzys to fit a 1.4 cam.
turbojolt
09-04-07, 11:27 AM
Oh sorry, thought you were asking if a 1.4 cam would go in a 1.3.
My post still applies anyway :p
Will need to change dizzys to fit a 1.4 cam.
only just lol
32/34 carb
1300 head & inlet
piper 285 cam/1400 cam
thats what i'm doing to mine with either a 4 branch for a 4-2-1 system from an sr
Jon_nova1
09-04-07, 11:52 AM
doesn't the sr just have a closer ratio gearbox?
mikey14sr
09-04-07, 12:33 PM
doesn't even have that in a lot of cases!
get rid of the 4-1 manifold & downpipe, & replace it with a 4-2-1.
Don't bother changing the carb/head
Then get a 1300 crank & rods & fit them
You now have a 1.4 hi-compression engine with a 1.2 engine number & no noticeable outer changes (for the insurance)
IT will go very quickly for a 1.2
I KNOW THAT but tuning a 1.2 is about as much use as bulls tits
If you want to mod a 1.2, i'd keep it sensible.
Something along the lines of novalicious's spec would be the max i'd bother do to one. If you can find second hand parts.
ok, but a secondhand 1300 crank & rods & a bit of mechanical knowledge would get you about 90hp for about ?50, or ?150 with some piston rings & a head gasket
turbojolt
10-04-07, 08:25 PM
ok, but a secondhand 1300 crank & rods & a bit of mechanical knowledge would get you about 90hp for about ?50, or ?150 with some piston rings & a head gasket
this sounds intresting mate how much work is involved in to geting the pistons and crank to fit
Jon_nova1
10-04-07, 08:29 PM
none, put the 1.2 pistons on the 1.3 crank and you get a 1.4 dont you? replace the piston rings for around ?40-?50, head gasket set ?15 and bolts for ?10, job done
turbojolt
10-04-07, 08:41 PM
and that is all i would have to do to get 90 hp
turbojolt
10-04-07, 09:18 PM
and tell insurance lol..
yes tell them *cought* lol
turbojolt
10-04-07, 09:39 PM
would a gsi gearbox or gte one fit to this engine
Jon_nova1
10-04-07, 10:08 PM
no
yes it would.... but need to be carefull not to get a WR box.
if you dont tell the insurance people, i hope to christ you dont drive outside the M25 :p
turbojolt
10-04-07, 11:06 PM
yes it would.... but need to be carefull not to get a WR box.
if you dont tell the insurance people, i hope to christ you dont drive outside the M25 :p
but they wont strip the engine to find out will they
paddy138
10-04-07, 11:19 PM
they wont strip the engine, gsi box will fit but your car will be harder on petrol as it is not designed to drive that gearbox, she would be quicker in the lower gears and slower in the higher gears.
turbojolt
10-04-07, 11:39 PM
they wont strip the engine, gsi box will fit but your car will be harder on petrol as it is not designed to drive that gearbox, she would be quicker in the lower gears and slower in the higher gears.
what so you would keep the orignal gearbox
paddy138
10-04-07, 11:44 PM
yeah or get one from a 1.3 or 1.4, mite have some difference, not sure tough
turbojolt
10-04-07, 11:47 PM
yeah or get one from a 1.3 or 1.4, mite have some difference, not sure tough
what like a sr gear box
paddy138
10-04-07, 11:55 PM
yeah but i dont know if there different, im sure some of the other members could tell ya
turbojolt
10-04-07, 11:56 PM
yeah but i dont know if there different, im sure some of the other members could tell ya
i heard the sr's have close ratio gearboxes
paddy, please learn about the nova gearboxes then come back and try agian,
the gte/gsi had F13's fitted, most were CR's but some are WR's its luck of the draw in that case.
the ratios are on my siglink site in the speed in gear bit. one of the links there has info for the exact ratios.
With a CR fitted it will accel faster in each gear topping out earlier than before with the WR box on.
you might use more fuel as the engine speed for a given road speed will be higher but not that badly.
paddy138
11-04-07, 10:47 PM
yeah isnt that why i said to ask some of the other members. why are all the premium members arrogant on this forum
sorry if facts seem arrogant... meh like i care :p
paddy138
11-04-07, 11:22 PM
yeah there facts but your ignorant about it the whole time, just say things dont be ignorant, it wont get you too far in life
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