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Pistons for '54 BN1

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RCarr

RCarr

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Hello all. I just acquired a 1954 BN1 - completely disassembled (except suspension) 2 owners ago in the mid 80's, and the project never completed. Most components were in cardboard boxes for the last 25 years, including the torn down engine, but it seems it's all there.
I have the engine in a machine shop now, and I need to choose pistons. I'd like to get a compression ratio of 9:1 or 9.5:1, and my engine shop suggests cast pistons since I want a street car and not a race car - avoiding piston rattles prior to engine warm-up. I can only find the 8.5:1 100M pistons as a cast piston. Any suggestions on a supplier that can give me what I'm looking for, or should I just go with the 100M pistons?
Thanks much for any advice here.
 
RCarr said:
Hello all. I just acquired a 1954 BN1 - completely disassembled (except suspension) 2 owners ago in the mid 80's, and the project never completed. Most components were in cardboard boxes for the last 25 years, including the torn down engine, but it seems it's all there.
I have the engine in a machine shop now, and I need to choose pistons. I'd like to get a compression ratio of 9:1 or 9.5:1, and my engine shop suggests cast pistons since I want a street car and not a race car - avoiding piston rattles prior to engine warm-up. I can only find the 8.5:1 100M pistons as a cast piston. Any suggestions on a supplier that can give me what I'm looking for, or should I just go with the 100M pistons?
Thanks much for any advice here.
Click to expand...
I use to use Jahns pistons with no problems, 9:1. Cast pistons are good enough for the street use with some mods to the engine. Also today there's some good cams to choose from!
You'll most likely have problems with the original Head and the new replacement aluminum Heads will give you a significant increase in performance. I wish they were available when I owned my 100!
 
RCarr:

Welcome!

I was in Hackettstown today.
We live in Morris County and have a summer place in Byram.

By the way, wondering who your machine shop guy is. I've had good luck with P & W Automotive Machining in Whippany.
 
Thanks Patrick, but it looks like Jahns is out of business now, something may pop up one eBay ??? Fast Street cams are available like you said, the Aluminum head may wait though.
 
The engine shop is Matt's Custom Automotive in Long Valley. This is the first time I've dealt with Matt. He was recommended by the guys down the road from him at Auto Tech. Auto Tech does British car restoration and repair and they use Matt for their engine work.
 
We campaign a '56 100 LeMans vintage race car, first time we build up the engine our machinist was a fan of JE Pistons, fast forward almost 20 yrs (we only run about 3 events per yr), we needed a total rebuild/rebore, different machinist, now we went with Venolias (might be spelled wrong). Bottom line is pistons are not super expensive to have made to what you need. We have and have never had, slap, I would suggest stage one is finding a really good machine shop and telling them what you want and let them source the pistons. If you go with a "stock" sort of set up, IE, production rods, and pistons that need the pinch bolts, let me know, I have a few sets of ARP fasteners I could sell you.
Thanks
Ed
 
Thanks Ed. I'll talk more to the machinist and see what he comes up with on forged pistons since you didn't get any slap. I am going with the original stock rods, so I may be in touch.
 
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