197 replies to this topic

[Sam Walters]

what im currently building...

low mileage non mg metro 1275 block, drilled for 11 stud
uprated oil pump
sw5 cam
centre strapped main
home modded head - austin 1300gt casting, ported and polished, larger inlet valves, a+ exhaust,polished valves, seats reground, cast marks removed from chambers, refaced.double sprung
a series rockers, bushed to 1.4

with 1.5 ratio rockers and bored to 1380 it would give 100bhp without the turbo provideing you have some crank/rod work and you have done your headwork properly.

[welshdan]

what im currently building...

low mileage non mg metro 1275 block, drilled for 11 stud
uprated oil pump
sw5 cam
centre strapped main
home modded head - austin 1300gt casting, ported and polished, larger inlet valves, a+ exhaust,polished valves, seats reground, cast marks removed from chambers, refaced.double sprung
a series rockers, bushed to 1.4

with 1.5 ratio rockers and bored to 1380 it would give 100bhp without the turbo provideing you have some crank/rod work and you have done your headwork properly.

thanks for the advice. however i feel that the engine im building will reach 120ish bhp at 8psi.

i have a few engines and parts knocking about, including 1380 flat top pistons, minisport stage 5 head, weber 45. if i was building a na engine id not use a sw5, it would be 286 or above!

doing the turbo as its something different, hopefully will give smooth power with a nice rev range, loads or torque, etc. if it goes welll il have a nice engine for little cash. i will then go on to build a 1380 turbo with full race turbo head. if the engine im building goes bang, iv lost nothing. a metro turbo was 93 bhp standard. im running slightly more boost, ported and polished head with larger inlets, a more suited cam. sligtly higher lift rockers, so 120 isnt unachievable. with the intercooler i could probably push to boost to 10psi, but dont want to push my luck. it will all be set up properly by a very good local rolling road.ta

[Ro8bieg]

just got my metro turbo engine yesterday, it's standard at the moment but my plans are:

Intercooler
New clutch and ligherned flywheel
X-pin diff
13-15psi
Maybe straightcut gearbox, not sure yet.
Hoping for 130bhp

[welshdan]

just got my metro turbo engine yesterday, it's standard at the moment but my plans are:

Intercooler
New clutch and ligherned flywheel
X-pin diff
13-15psi
Maybe straightcut gearbox, not sure yet.
Hoping for 130bhp

id change the cam. the standard turbo one is the same as the non mg metro cam. also not sure about that amount of boost. probably would aim for 10 max on a standard intercooled engine. im sure thats what a lot of the turbo guys say. you wont need a straight cut gearbox, just 4 pin diff and sc drop gears.

[Jordie]

your going to have to modify the engine and compression ratio to run that sort of boost. as suggested above.

[Nickh_16]

998, maniflow stage 1 kit, 998 12G295 cooper head and AAA needle, not much but i haven't even passed my test yet lol

[Tomf]

• 1380 block, (1275 bored to 73.5mm)
• powermax 73.5mm (AE 20659)
• Kent MD 286 cam
• Duplex lightened timing chain
• Ultra light flywheel and back plate
• High flow water and oil pumps
• Standard re-build gearbox.
• 3.65 diff
• Gearbox gasket set
• Block gasket seat
• 2 Core radiator
• HIF 44 carb

[bebbinator]

hi i am building a 998 bored out to 1100 with an 8 valve bmw k100 cylinder head forged pistons and conrods exturnal oil feed and webber 45 carbs and it should put out about 100 bhp with a mpi front mounted radiator.

if i do the same to a 1275 i will get nearer 180bhp

Edited by bebbinator, 16 July 2008 - 09:31 AM.

[Sam Walters]

that cam and turbo dont go hand in hand.

[Sam Walters]

998 forged pistons

where where where!

[spikyrob]

Here we go:

Bill Richards 1380 cc road/race offset bored and decked A+ block (no idea of compression ratio yet)

73.5mm forged pistons which Bill machined lighter

Miglia spec con rods lightened, balanced, shotpeened and polished

Turbo crank, nitro carburised, wedged and cross drilled, centre main strap fitted

Race/rally head 36/31 mm waisted stem race valves, piper retainers and springs, titan full roller rockers

kent 288, piper vernier timing gears

weber 45 DCOE on maniflow steel inlet

Maniflow twin box race system with phase/stage 2 maniflow LCB

cometic triple steel shimmed head gasket

Megajolt with KAD timing wheel kit and custom made magnacore HT leads

Hits 8k rpm no problem

Gearbox etc:
AP racing clutch plate, orange diaphragm, ultralight steel flywheel
Minisport SC drops
Minisport SCCR gearset
Minisport 4 pin diff

Oil cooler
alloy rad
minispares toothed belt kit (alternator, crank, water pump)

Acheived 96.3ft/lb and 110bhp at the fly running on twin 1.5 SUs and no megajolt,
With weber and megajolt hopefully 100+ ft/lb maybe 110/115 ish bhp

future plans:
M45 supercharger (decompression plate due to head CC's)
or
Honda B16

Edited by spikyrob, 18 February 2009 - 08:09 PM.

[bebbinator]

998 forged pistons

where where where!

they are not 998 pistons they are custom 1100 pistons built by omega pistons

[alexcrosse]

hi i am building a 998 bored out to 1100 with an 8 valve bmw k100 cylinder head forged pistons and conrods exturnal oil feed and webber 45 carbs and it should put out about 100 bhp with a mpi front mounted radiator.

if i do the same to a 1275 i will get nearer 180bhp

twin 45's on a bored 998... hmmmm

[mini93]

hi i am building a 998 bored out to 1100 with an 8 valve bmw k100 cylinder head forged pistons and conrods exturnal oil feed and webber 45 carbs and it should put out about 100 bhp with a mpi front mounted radiator.

if i do the same to a 1275 i will get nearer 180bhp

reet...well you should know that to make up the difference for the 998 and the 1098 the CRANK is different than 998 the bores are the same, also the pistons are different where the piston compression height is different...also do you know how much work is involved in putting a K series BMW head onto a small bore engine??

[bebbinator]

yea i know all of that but my dad is a mechanic and i have been helping him since i was 11 and its not that hard to fit a k100 head on a small bore block and they are more reliable ...