Also used in big bore 948cc engines
If you are looking for great longevity from your 998cc engine, these 4-ring dished pistons could be the best answer at rebuild time. Compression 9:1. Nural brand, circlip type.
Question:
Looking to purchase these for my 59 Bugeye. A couple of questions:
- What size is the required bore for these pistons?
- Can I retain the stock 948 connecting rods?
- Are there any other modifications required to run with these?
- Are there any suggested modifications?
Answer:
Going from the 948 to the 998 +.020" should be fine. The 948cc piston is 2.4775", the 998cc pistons are 2.5420" and 998cc +.020 =2.562". The rods are the same, the pin height for both pistons is the same (1.342").
The change represents taking a 948 block and boring it +.0845" over (from standard).
We would suggest getting larger valves in the head to take advantage of the larger displacement. If you could find a 12G206 or 12G295 head - those have larger intake valves - or just go to the large intake valves in your head. That plus more of a street camshaft and maybe a header and exhaust and you'd be good to go.
Spridget Mania Tech Team
The Spridget Parts and Accessories Experts
