43 replies to this topic

[A362 TTU]

My 998 head is marked CAM4810 not CAM4180

[firefox]

my head is marked dick62

[twrminisport]

This is all ridiculous.
It is not your "engine" that is leaded or unleaded. It is your cylinder head.

Therefore look at your cylinder head casting number.

Because BL used so many different heads for so long the engine number does not really tell us anything. This also only tells us how is LEFT the factory and not what it is now

Sorry for the attitude but you will need your head casting no. to be sure. (Its under the rocker cover in the middle under the rocker shaft.

Jesus

I'm afraid that at some point you've been seriously misguided...

The engine number tells you exactly the specification of the engine as it left the factory, ok, some of the information has been lost over time, especially information from the 70's, however, 80's onwards is very well documented...

The casting number on the head means very little, ie all 1275 heads post cooper S are 12G940 castings, whether it be from a GT, turbo, spi, Metro, unleaded or leaded, and the same is true for 998 and 1098 A+ heads which are CAM4180 castings, irrespective of their specification.

For the OP. Yes CAM4810 is fine. Typo. That is an unleaded head.

FAO GUESSWORKS.
On the subject of 1275 heads i would agree with you as they are all 12g940 apart from the 12A185 and AEG163 which were for the Mk1 Cooper S then later Mk1 and Mk2 Cooper s Respectivly, However as the OP stated he has a 998 i awnsered as such.

Your information on the smallblock heads is somewhat lacking. The CAM4810 is not the only 998/1098 head as your post suggests. The CAM 4810 has only one specification. It has 26.99mm Inlet valves and 25.4mm exhaust valves, nominal cc of 25.5, and was fitted to the 998 Mini A+ as the LEAD FREE head.

However there are many other small block heads. the
2A628 for example which was fitted to 998 and 850 Minis aswell as the 948 sprite. 26.99 Inlet and 25.4mm exhuast, 24.5cc
The 12A1456 was fitted again to 998 and 850 Minis aswell as the 948 sprite. 26.99 inlet and 25.4mm exhuast 24.5cc
The early 998 Coopers had a 12g206 head which was later replaced by the 12g295. 30.93mm Inlets and 25.4mm exhaust. 28.3cc
There is also the 12g202 which was fitted to the 997 cooper and the 1100. 29.36m inlets and 25.4mm exhausts 26.1cc
ALL OF THE ABOVE ARE LEADED HEADS. - There was also different head numbers such as the 2A629 which was for the 948 MG/Sprite, A35 and Minor aswell as another head for the 803cc Morris Minor. - But we dont need to go into that on a Mini Forum....

The CAM4810 is the ONLY UNLEADED head and was produced from the factory as such.

Jesus

[firefox]

has someone spit their dummy out

[mohammed]

my cylinder head states CAM4810, so that mean its unleaded..

thanks everyone

[[email protected]]

The information above by TWR is being mis interpreted and/or being given out incorrectly. The later CAM4810's are unleaded, it's not true to say they are all unleaded. CAM4810 is a generic A+ casting number, unless you know for certain that the head has been converted either by markings of whoever did the conversion, or going by the engine number, then yours will most likely be leaded

[kingbenvolio]

Looks like theres going to be a punch up!

[Shifty]

Yup, the only way to know if you have an unleaded engine is by the engine number(assuming the car is still fitted with its original head)

Actually that's not the only way, the other way is to pop a valve out and see if its fitted with hardened seats.

The head number won't tell you.

I'd also suggest you re-read guessworks post as well, he didn't say that the only head fitted was a cam4810. I'd also refrain from casting any doubt on guessworks knowledge as well.

http://www.theminifo...l=&fromsearch=1

http://www.theminifo...l=&fromsearch=1

Both these topics seem to show a lack smallbore head knowledge?

[[email protected]]

No Punch up lol, but you need to be armed with the right information, as I and guessworks have given you. The other info given is incorrect as it stands

[twrminisport]

I really would like to see a leaded CAM4810 head, maybe theyve got some rocking horse droppings at home aswell...

Edited by twrminisport, 20 December 2011 - 10:44 PM.

[Shifty]

Can't help with the rocking horse poop, but I do have a quote from "AC Dodd"

"CAM heads were certainly unleaded from the middle of '89, before that this head was leaded just like all the others. the casting number does not relate to whether the head has inserts or not.

AC"

Taken from here.

http://www.minifinit...ic.php?p=881186

[[email protected]]

I really would like to see a leaded CAM4810 head, maybe theyve got some rocking horse droppings at home aswell...

I have in the region of 70 you are more than welcome to come and view.....

[Guess-Works.com]

My 998 head is marked CAM4810 not CAM4180

Yes, apologies, I typo'ed the 1 and 8 the wrong way round in my statement....

Your information on the smallblock heads is somewhat lacking. The CAM4810 is not the only 998/1098 head as your post suggests. The CAM 4810 has only one specification. It has 26.99mm Inlet valves and 25.4mm exhaust valves, nominal cc of 25.5, and was fitted to the 998 Mini A+ as the LEAD FREE head.

However there are many other small block heads. the
2A628 for example which was fitted to 998 and 850 Minis aswell as the 948 sprite. 26.99 Inlet and 25.4mm exhuast, 24.5cc
The 12A1456 was fitted again to 998 and 850 Minis aswell as the 948 sprite. 26.99 inlet and 25.4mm exhuast 24.5cc
The early 998 Coopers had a 12g206 head which was later replaced by the 12g295. 30.93mm Inlets and 25.4mm exhaust. 28.3cc
There is also the 12g202 which was fitted to the 997 cooper and the 1100. 29.36m inlets and 25.4mm exhausts 26.1cc
ALL OF THE ABOVE ARE LEADED HEADS. - There was also different head numbers such as the 2A629 which was for the 948 MG/Sprite, A35 and Minor aswell as another head for the 803cc Morris Minor. - But we dont need to go into that on a Mini Forum....

The CAM4810 is the ONLY UNLEADED head and was produced from the factory as such.

Jesus

If you had cared to read the sentence I actually wrote, you would notice that I said, "998 and 1098 A+ heads", and even though the information you have provided on the history of the small bore head is very useful, and the statement that the only head which left the factory compatible with unleaded fuel was the CAM4810 is true, I will concede that point, but that does not mean all CAM4810 heads are unleaded.

All the heads you mentioned were replaced by the CAM4810 casting with the introduction of the A+ engine... in circa 1980, the best part of a decade before the requirement for the hardened seats to be added which was first introduced into the mini range with the Mini Sky and Rose in 1989, engine number series 99HD81P.

Edited by Guess-Works.com, 21 December 2011 - 09:09 AM.

[jaydee]

2A628 for example which was fitted to 998 and 850 Minis aswell as the 948 sprite. 26.99 Inlet and 25.4mm exhuast, 24.5cc

My checkmate come originally with that cylinder head, it was unleaded though.
You cant tell without inspecting cylinder head IMOH
There was a lot of business around unleaded conversions during the 90ies.

[eeae6000]

what if mine is german spec 88 austin mini, did they still have unleaded back then