IMPORTANT NOTICE: Due to the COVID related issues your order may take longer than usual to arrive.   Read More
We have detected you're not on the correct site for the car you have selected! Click the green button below to go to the correct site.
Select your car: 
BMW Mini Cooper

 Engine size

 Created by: croc7
   Forum Width:     Forum Type: 

 Posted: Apr 30, 2020 05:26AM
Total posts: 4134
Last post: Oct 13, 2020
Member since:Oct 8, 2011
Cars in Garage: 0
Photos: 0
WorkBench Posts: 0
I think I have heard them reffered to as 1050s. I have been building a few and they make a nice unit.
I use an A+ block and the late 998 press fit rods and flat to 10 to 1 pistons. Bore , clean , hone , deck
, cam bearings and freeze plugs. Grind or polish the crank and balance the complete assembly. I use
two part Cooper balancer and light flywheel and back plate. If using a 940 cyl head I relieve the block for
exhaust valves and drill and tap for extra studs. As long as I can get them I prefer to use the Cooper/
1100 295 cyl head castings. I use cast valve guides, hard exhaust seats, O/S late lead free triple groove
intake and exhaust valves. Head needs to be CC ed and a pretty good wack surfaced to reach 10.2 to 1.
I built one for a customer and used the Swift SW5 cam. The next one I build will get a Kent 266.

I have to use four different machine shops to get all my machine work done. The only shop who bores
small bore is an hour drive each way. The last 998 I did I ordered two sets of pistons and a couple of
sets of press rods. I had two blocks roughed out. I also had a second 295 cyl head done at same time.
All it needs is honing to finish size, balance and order a cam.

If someone needs nice 998 for a summer project let me know. Steve (CTR)

 Posted: Apr 29, 2020 09:43PM
Total posts: 3500
Last post: Nov 22, 2020
Member since:Feb 26, 1999
Cars in Garage: 0
Photos: 0
WorkBench Posts: 0
Originally Posted by croc7
What is the displacement of a 998 bored .060” over?
bore 2.543 standard stroke 76.2mm at +0.060" would give you 1046

 Posted: Apr 29, 2020 08:20PM
Total posts: 802
Last post: Nov 18, 2020
Member since:Aug 15, 2002
Cars in Garage: 0
Photos: 0
WorkBench Posts: 0
What is the displacement of a 998 bored .060” over?