As Roger says AX and 711M are mutually exclusive. It will be one or the other.
This will be cast on the side of the block.
SAMCOR surely is South African, so likely to be AX.
Democratic dissent is not disloyalty, it is a positive civic duty
The 711M is an excellent block and can be tuned right up to full race spec, but the AX is even better. You cannot take a 711M to 1800ccm, but as a general rule the AX will bore out that far; it is ESSENTIAL to check bore wall thickness before you try though because you will occasionally find a "rogue".
The AX is also slightly heavier and stiffer, but it is significantly smoother running as a result. You may well find that it liberates a couple of extra horsepower for the same reason. Finally, it appears to be cast from a different material because it suffers less bore wear than the 711M.
I have a paper from when I took the casting notes. I definitely have "95 AX" on there, but I thought I had 711M as well. I didn't know there would be a discrepancy over the presence of both. I will have to look at my notes again to confirm and get back to you. I am interested in converting to 1699cc because one of the cylinders has a rust ring from when previous owner let it sit and seized. the cylinder was honed, but the ring is still evident. Im not sure if it will affect tuning much and minor uneven throttles on one of my DCOEs is still an issue.
The car is going to get a top to bottom "cleaning up" with a few upgrades. I would like the displacement at 1700, if parts are available, a 234 cam or mid-range streetable equivalent, T-9 box and Quaife ATB LSD in the Ital diff, to be in the works. I recently read the refurb Itals for the scholarship cars have welded bearings to fix a wheel loss issue encountered in competition. Fun.
Who would be the go-to for the 1700 pistons and rings?
I have the T-9 and bells, a Tilton roller rocker set, and shortened drive shaft. I might have the clutch plate.
Thanks, you guys are great!
The link below shows where you can get them. 83.5mm will give 1700ccm and is just very slightly larger than the bore for the +.090" pistons that Caterham used which gave about 1690ccm.
Note that the standard +.090" pistons that Caterham used are nowhere near as good as the forgings from Accralite; these are much stronger, significantly lighter, and despite much lower friction from the rings they actually seal much better, though they do require a plateau honed bore finish.
Believe it or not, just changing to the Accralites will typically add around 10bhp to the top end of the power curve simply due to lower friction (you can actually feel the difference when you install them into the bores).
You may need to machine them to get the correct compression ratio and while most valves will suit the valve pockets, you need to check that you have adequate clearance.
No, I never found the 711M cast. It would have been easy enough to see, above the starter, based on a photo. Im happy enough to have an AX lump. I think I want to build up the lower end to ensure it never grenades. Not that I drive it hard or compete, I can only afford one seven. I would be semi-aggressive street/road.
Im not entirely sure if I want to overbore to 1700. I would never be able to sell it to the vintage FF people, if it were to come to that. It may be possible to come close to 1700 performance without the overbore? I would remain less "square".