60 replies to this topic

[Reece Jackson]

hi there everyone i dont know if this has been mentioned before but would it be a good idea to have a specific topic just for small bore engine i.e 850,998,1098 power outputs so we can share engine specs and tuning ideas i'll start with mine:
998 a+ +60 pocketed block decked
12a1451 crank lightened balanced wedged nitro carbonised
rods lightned balanced shot peened
fully steel flywheel and backplate ceramic paddle clutch orange diaphram
ae 20950 flat top pistons
12g940 cylinder head full slark spec 37.5x31 race valves skimmed 120 thou 240lb double valve springs
fully lightned twin chain duplex timing gear
ctr 930 camshaft isky followers
1.3.1 high lift rockers
lumention ignition
weber 45 38mm chokes
7"manifold
gearbox:
minispares clubman sccr
0.954 sc drop gears 23/24
3.7fd
the result of my engine is around 90hp at the wheels revving to 9'000rpm with about 100lb/ft of torque
i just think it would be really usefull for us to share our specs and outputs to help new comers to the world of tuning small bores!! thanks Reece

[Racer_Pete]

This has been mentioned many times, I also think it would also be a good idea to have a small bore section, TurboMinis have a 998cc section so I cant see why we dont. There are lots of intresting small bore builds on the forum with differing specs. Do you drive that on the road?! Never heard of a 1046 with 38chokes! sounds like a beast to drive.

Heres my spec....
-1061cc A+ 11Stud Pocketed Refaced Block,
-Prepared By Classic & Modern Engine Services
- +.80 Mega Type Flat Top MSC Pistons
- Hif44, Smoothed Butterfly, Minispares Inlet, K&N
- 12G1805,Swiftune ex Mini7 'FULL RACE' Spec Head
- 37x31 Rimflow Valves, 30* Seats, Bronze Guides,
DV Springs, Steel Retainers, Pushrod Holes Sleeved,
14.0cc In Head, Huge Ports,
- Swiftune Billet SW10 Camshaft
- Swiftune Alloy Duplex
- Maniflow LCB & 1.75 single box
- MED Lightend Rods + ARP Rod Bolts
- MED Wedged & Backdrilled Crank,
- Mains Ground 0.20' Bigends 0.10' Thrusts 0.10'
- MED RACE Spec Leccy Dizzy 286+, No Vac, Lightend Dizzy Dog
- Lucas Sports Coil + Lumenition Leads
- Oversized Lead Competition Main & Big-end Bearings + Thrusts
- Isky-type Lightend Followers
- Leccy Fuel Pump
- Millers CTV 20W50 Semi-Synthetic Oil (currently miniral)

Clutch;
- M/S Pre-Engaged Ultralight Flywheel
- MED Lightend Backplate
- AP Orange Diaphram
- AP Rally/Race Friction Plate
- Whole Rotating Assembly Dynamicly Balanced By Classic & Modern
- Pistons, Rods, Crank, Clutch Assembly, Damper.

Gearbox;
- Rebuilt by Heathrow Transmissions
- MiniSpares 4Sync SC/CR Clubman Gearset
- MRA 1:1 Straight Cut Drops
- MiniSpares X-Pin Diff
- 3.64 Final Drive
- Centre Oil Pickup
- Paul Wigginton Alloy Windage Tray
- KAD Quickshift

[Reece Jackson]

my engine is an autograss engine that sits at full revs for at least 2 mins it's geared to do about 70mph in second gear and yes it would be really good to have a 998 section seen as the current rage for tuning them!

[Reece Jackson]

This has been mentioned many times, I also think it would also be a good idea to have a small bore section, TurboMinis have a 998cc section so I cant see why we dont. There are lots of intresting small bore builds on the forum with differing specs. Do you drive that on the road?! Never heard of a 1046 with 38chokes! sounds like a beast to drive.

Heres my spec....
-1061cc A+ 11Stud Pocketed Refaced Block,
-Prepared By Classic & Modern Engine Services
- +.80 Mega Type Flat Top MSC Pistons
- Hif44, Smoothed Butterfly, Minispares Inlet, K&N
- 12G1805,Swiftune ex Mini7 'FULL RACE' Spec Head
- 37x31 Rimflow Valves, 30* Seats, Bronze Guides,
DV Springs, Steel Retainers, Pushrod Holes Sleeved,
14.0cc In Head, Huge Ports,
- Swiftune Billet SW10 Camshaft
- Swiftune Alloy Duplex
- Maniflow LCB & 1.75 single box
- MED Lightend Rods + ARP Rod Bolts
- MED Wedged & Backdrilled Crank,
- Mains Ground 0.20' Bigends 0.10' Thrusts 0.10'
- MED RACE Spec Leccy Dizzy 286+, No Vac, Lightend Dizzy Dog
- Lucas Sports Coil + Lumenition Leads
- Oversized Lead Competition Main & Big-end Bearings + Thrusts
- Isky-type Lightend Followers
- Leccy Fuel Pump
- Millers CTV 20W50 Semi-Synthetic Oil (currently miniral)

Clutch;
- M/S Pre-Engaged Ultralight Flywheel
- MED Lightend Backplate
- AP Orange Diaphram
- AP Rally/Race Friction Plate
- Whole Rotating Assembly Dynamicly Balanced By Classic & Modern
- Pistons, Rods, Crank, Clutch Assembly, Damper.

Gearbox;
- Rebuilt by Heathrow Transmissions
- MiniSpares 4Sync SC/CR Clubman Gearset
- MRA 1:1 Straight Cut Drops
- MiniSpares X-Pin Diff
- 3.64 Final Drive
- Centre Oil Pickup
- Paul Wigginton Alloy Windage Tray
- KAD Quickshift

what power does that put out mate

[richardsoniscool]

90bhp / 100 lb/ft from a 998. that is MENTAL!!!!!

[Racer_Pete]

what power does that put out mate

Still being built, but hopefully around 80bhp at the wheels with that head, The cam is the limiting factor for me because of how much meat has been taken of the head, & I cant have a cam with to much lift because it will hit the pockets. Whats the spec of the cam your using?

[Reece Jackson]

im not entirely sure on the exact spec of the cam mate i just know its a 930 i,e 649 profile but it may have been reprofiled for short circuit racing my engine has that much power it makes it that un reliable and very cost worthy but trust me its worth it as you will know pete my head is also a mini seven spec head

[Reece Jackson]

having just worked out my power to weight ratio my car will have around 250hp per ton!!

[number4]

Hi everyone

I've had this burning question that nobody could answer me yet. Never met anyone that did this. Regarding block pocketing, what does this mean/involve. By using my imagination I thought it must be something like the little picture I drew up here. With a top view of the bore and an side sectional view of the block. Am I assuming the right thing here? And if so, what would typical values of D and H be? Now, further thought made me think that this would totally bugger up the head gasket seating surfaces. How does one overcome this issue?

Regards
#4

Attached Files

•  borepocket.JPG   13.94K   11 downloads

Edited by number4, 26 October 2009 - 01:45 PM.

[Reece Jackson]

block pocketing is a term used when fitting a large bore cyl. head i.e 12g940 etc. to a small bore block it is done to accomadate the size of the larger valves and cam lift the size of the pocket is different on every engine depending on valve size cam lift etc. it is normally only on the inlet valves.

[number4]

Yea I am aware what the term means, I just don't know how it works. Can somebody explain this to me please?

[benpopham]

This is a brilliant idea.. I think we definitely need a small bore section, Im building a 998 +40 with a swifty 940 head and finding info of these builds has been a nightmare.

Il post up the spec when I get into work.

We need to nag the admin for a new section, this would be very useful

Ben
[email protected]

[benpopham]

Heres my spec... hoping for around 80hp


998cc Block + 0.40'' Pocketed
compression ratio of 10.5 to 1
AE +0.40'' pistons press fit
Swiftune 12G940 stage 3 head
3.4 ratio final drive
hardened diff pin
wedged & backdrilled Crank
lightened rods
Weber DCOE45 using one side
Swiftune SW5-07 cam
Swiftune timing gears
Swiftune Straight cut roller drop gears 1:1
Titan 1.3 ratio Roller Rockers
MED ultralite pre-verto flywheel
Ultralite billet MED back plate
Orange diaphragm
Maniflow se7en's manifold
Maniflow stage 2 LCB
Carbon 4 blade Fan
Set of Lightened ISKY cam followers
PoleStar engine management system

Ben

[email protected]

[james962]

Some awesome looking spec lists here people! I too think we should have a 998 section. I would love to attend a shootout, although i'm just in the "collect parts" phase at the moment

I wonder where your getting your carbon fan from Ben?

[benpopham]

oh theyl be more than just a fan!

Im only in the long and painful 'collecting parts' phase too... nice to have shiney bits arrive through the post (when theyre not skiving!) every few days though!

Ben