19 replies to this topic

[jeffberg]

I think I'm gonna go look at that Hornet on Sunday
I need to know how I can tell what size engine it has
I don't want to go by the VIN on the car because the engine could easily have been changed.

So how can I tell the exact engine size.... maybe year too if thats possible just by looking at the engine?

[Al*]

Talk to DavidJ He had one.....has one?......sold it yet.....oh never mind.

send DavidJ a pM.
i would a ssume it's a 998 though.

Al

[bluebottle]

apart from the little alloy plate just in front of the head, a lot of earlier cars had a plate rivetted on the back of the block, its down by the gearbox flange, but i cant remember which side, it will have a large 998 or 850 stamped in it

[Pavel]

Just look at the engine number... and tell us here what is is... Even if the engine was changed, the new engine will still have an engine number

[jeffberg]

is there any way that I can get the decoder now so i don't have to go see this mini 2x
its like 2 hours away so i don't want to have a wasted trip. I would just like to tell there.

[Woody]

The first 3 digits give the engine size :
99h = 998cc
10h =1098cc
12h =1275cc
i think 850cc is 80h , not sure on that one,
I think this varies on re-con units and some aftermarket engine builders make up their own numbers .

[David_J]

Hi,
I have to bow to the knowledge of others here as I'm afraid I wouldn't know the answer. I would go on the info given by Woody.

Hornets and Elfs are identical to minis in most ways so any buying guides you can find on minis will apply.

Best of luck.

[bluebottle]

here's a handy link for you, it gives all 'a' series engine numbers, even the all the prefix's for different cars like the hornet.

http://www.mgcars.or...ic/codeseng.pdf

[jeffberg]

thank you
thats exactly what i was looking for
just checking.... the info I am looking for is on page 5
"BMC 'A' Series Engines. ( 1952 to 1999)"
Correct?

[bluebottle]

yep, thats it, note the different suffix's for the honet/elf engines.
although to be honest, i'd be suprised if a car that age had its original engine, but you never know!

[Cooperman]

You can't trust the engine plate, it could have a 998 cc engine number on a 1275 engine or vice-versa.

Now, here's how to really tell:

A 998 cc engine always has two cam follower access plates in the back of the block, just behind and below the manifolds. They are about 6" x 3". No other Mini engine has these EXCEPT the Cooper 'S' units. However, ALL Cooper 'S' units have 10 head studs plus one head bolt (by the stat housing), whereas all othe Mini variants have 9 studs.
If it's a genuine 'S' engine it could be 970 cc, 1071 cc or 1275 cc. It doesn't really matter, as any genuine 'S' engine is worth serious money, so if you got an older Mini with an 'S' engine you've scored very well, but that's extremely unlikely.
By the way, there are no exceptions to the above rule about cam follower access plates. So just look down the back of the block and then count the head studs.
It is possible, I suppose, that someone could have added 2 extra holes to the block of a 1275 non-'S' block and added the extra stud & bolt, but then there would be no cam chest covers. The head casting on a 1275 unit will normally be cast with the number 12G940 and you can check this if you take off the rocker cover. Early Cooper 'S' heads were marked 12G163, but there are very few of these now as most cracked years ago. If you find a good -163 casting please let me know!
The best head for a 998 cc car is the 998 Cooper head, part number 12G295. If you find one, then buy it immediately - they are very rare and add a lot of bhp to any basic 998 engine, especially if gas-flowed and skimmed a bit. I've got 3 in my workshop at present - no, they are not for sale!

So it's simple really, you just have to look.

I hope this helps.

[bluebottle]

or it could be an 850.....

[Cooperman]

Sorry, me again. I didn't mean to mislead anyone, but the original 848 cc engines also had the cam follower access plates in the back of the block. I assume the car you are looking at would be post that engine standard anyway. It's difficult to tell the difference between an 848 and a 998 though without taking the head off and measuring the stroke. You can measure the stroke approximately by putting a pencil down the bore, marking it at TDC and again at BDC, then measuring between the two marks. It's accurate enough if you are careful. You can use a digital vernier if you have one.

[bluebottle]

i'm not sure the owner would to chuffed if you turned up and started taking the head off to measure the stroke!..... :grin:

[Sfanatic]

Use a long pencil like someone else said to measure the stroke without taking the head off.
The 1100 engines, but not the 1300 engines, also has cam chest covers, but they were just 998 engines with a long stroke crank - same basic block.