12G295 Head to Australia
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Assemble & run in with WD40.
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Lost the camper trailer spare wheel/tyre when the welds & mounting plate failed (too much 4x4 travel) when I drove into Purnululu but recovered it early the next morning.
Looking forward to getting home & have made more notes about getting ROO ready for the Alcan 5000 Summer Rally in August 2018. Starts in Kirkland, Washington, routes through B.C. & Yukon territory and ends in Fairbanks, Alaska. Approx. 500 TSD stage miles, 4,500 miles of touring...over 9 days.
The 1098 build up to 1185cc with RE +100 pistons/rings, Paul Ivy race valves, Cooper S springs, 1.3 roller tip rockers, new RE cam grind/followers, fine hone finish/1.5 thou clearance in bores, not less than 8 thou ring end gap, NGK B5ES plugs, std 998 slot drive oil pump, RE intake for HIF 44, Maniflow freeflow header into Maniflow or RC 40 exhaust.
Assemble & run in with WD40. Crank will be crack tested, polished, oilways improved & all rotating parts balanced. NEED light flywheel.
(heavy wheels break cranks). Transmission will be rebuilt with pot joint outputs, pressurized layshaft...maybe rall clutch spring & standard plate.
Graham says more than 75 hp should be on tap...hiked his thumb upwards twice when I mentioned what I would be happy with 70-75..."more" was his one word reply.
Going to make some additional inquiries here in OZ about HIF 44 after I get back to Brisbane.
Home on the 26th, will recover ROO from storage and keep myself busy with the '61 Countryman build & ROO's new power unit.
PHOTOS - getting set to cross the Pentecost River (after Chamberlain & Salmund Rivers had joined in) & plunging in on Gibb River Road heading from El Questro to Mount Barnett Roadhouse & Manning Gorge
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There is nothing inherently "wrong" with long stroke engines, in fact just about every tractor engine (what the A-series started as!) and most diesel engines have a long stroke, generally better for torque. But, for performance, a small engine has to spin, and the 1098 stroke is just absurd... longer than many 5 or 6 liter V8s. Add in the tiny bore that does not allow any room for big valves, and the noodle crankshaft (particularly the older 1.75 inch main bearing journals), crazy high piston speeds as revs increase, not exactly a recipe for high performance! Think of the Chevy V8 small blocks of the musclecar era.... The 350 had a stroke of 3.48 inches, but when the 69 Z28 Camaro came out with a high revving 302, it was the same block with a 4 inch bore, but only a 3 inch stroke crank.
The 998 has the same bore and about 1/4 inch shorter stroke than the 1098, so should be much happier to rev, and the 1098 pistons are also shorter with a higher pin height (or they would stick out the bore with the longer stroke!), and the modern 3-ring Russel 68mm pistons don't quite resemble a beer can like the stock 998s do! Yes I'll have to chop about .140 from the deck (about half the difference in stroke) to bring the flat top piston back up to the top of the bore with the shorter stroke, but I'll decide that based on which head and what compression ratio I can live with. The rest of it.... late rod change with straight cut gears, probably a 3.76 FD (building for auto-cross, not highway!), a very light flywheel, an actual crank damper. Still not sure about the head and carb.
Kevin, I'm curious about the BK450 head gasket as you're using the small bore head.... that gasket is good for 1380 bore size around 2.9 inches. Seems it would risk not covering water ports, and only provide minimal coverage of the deck.... It's only about .115 inch between 2 & 3! I had good success with the guys at Cometic making me a custom solid copper gasket from a template of the deck I sent them (for a different engine), so I may do that again for the small bore.
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Just dropped my 1107 A+ block off at the machine shop to get the deck shortened by .0145" and left with a ground finish to suit the copper head gasket. Rather than moving waterways in the block and the head, I'm trying a copper 998 gasket first as I can always plug and move if it doesn't work, but cant unplug and re-move if the head goes on a more sensible sized block.
Just dug out a video of my 1150 on the rollers back in 2009, taken on one of the initial runs that shows 45 whp and 62 at the flywheel. Considering that it was cobbled together out of found parts - used MG Metro cam timed in about 7° retarded and an unknown source 12G295 head - I'd be very disappointed with less than 55 whp from the 1107 as it will have a more adventurous cam and will rev higher.
60 from a 1380 would have me wondering where they escaped to, and was it worth using up a block to get there - we got more than that from the tired 1310 in Tigger !
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Jemal, we recently built an 1108 using GR's 68mm pistons and a stock 998 crank. Had to mill a bunch off the block as the pistons have 1098 deck height.
Head is a ported 202 with 998 Cooper intakes and 27mm exhausts. Gasket is a BK450, I had to move a few water holes to use it with the 202 head. Camshaft is an RE266SS, rockers are stock 998/1098 pressed steel.
When built, it had twin HS2s, now with a 40DHLA Dellorto using 33mm chokes it goes much harder.
Not had it on a chassis dyno yet, but it feels like well over 50HP ATW.
It spins hard beyond 7000 and is very smooth compared to a 1098.
Kevin G
1360 power- Morris 1300 auto block, S crank & rods, Russell Engineering RE282 sprint cam, over 125HP at crank, 86.6HP at the wheels @7000+.
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"Everybody should own a MINI at some point, or you are incomplete as a human being" - James May
"WET COOPER", Partsguy1 (Terry Snell of Penticton BC ) - Could you send the money for the unpaid parts and court fees.
Ordered so by a Judge
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We are taking a Lotus 7 America with 948 power to Talladega, it will require 110 mph to stay up on the bank. The engine had been rebuilt some time back but was always a little weak and unwilling to rev. We rebuilt it with performance in mind and it is so much better. Before it was hard pressed to rev to 5000. Now it revs cleanly to 7000 plus and is a much better power unit.
I also have building a big bore 998 in mind. While they cost just as much as a 1275 to rebuild the cores are cheaper. And we know what British car owners are.
As for the bus trip count me out I recently did two 14 hour bus rides in a week and it all but killed me. I was wondering what GR was going to do to the 295. I have bought the correct pilots and seat cutters for my local machine shop. They are only used with my small engine cyl. heads. I did not expect him to take much out of the ports. Looks like he blended the new hard seats into the valve bowls, Some heads are very close just as cast. While working with Dave Tabor I became aware of 5 different things to look for in a cyl. head. Following his instructions I bought 17 1275 cyl heads before he would accept one for porting. I'm once again buying 940 cyl. heads and always looking for 295 castings. Steve (CTR)
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I am very curious how that turns out! I know that HP numbers are very arbitrary without relevant comparisons, and certainly one dyno might be very different from another. However, given that one of our 1380cc engines with a performance head shows about 60HP at the wheels, and that my tire shredding 13 to 1 1380 full of tricks shows about 90HP, I am hoping for about 45-50 with my 'super small-bore'! That would be about double or better than most 998s, on par with entry level 1275s..... and what you might reasonably expect from yours!
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But after 34 out of 44 hours on a Greyhound bus from Brisbane to Sydney return, I got back to Queensland, after a terrific visit with Graham Russell in North Rocks, New South Wales, with the OEM 12G295 head prepared with hardened exhaust seats, seats cut for Paul Ivey race valves (spring height for S springs), new +100 flat top pistons (chamfered to eliminate gasket interference), new faced cam followers, new grind on a new C&C'd cam blank, new spring caps, a little cleanup in the ports...and a new RE alloy intake for HIF 44.
Will use Maniflow Cooper Freeflow exhaust into RC 40. Will rebuild the standard 1098cc in the Aussie Mini Window Van into an 1185cc with perhaps 85 or more HP. Need lightweight flywheel and good 1.3:1 roller tip rockers.
Off Friday in a Toyota Land Cruiser for the Gulf Country, followed by the Gibb River Road in the Kimberley.