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TR4/4A 86mm vs 87mm liners/pistons - TR4

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MrAlex

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I am a little confused. Vendors are selling both 86mm piston/liner sets and 87 mm piston/liner sets. Same price. Why would I order the 86mm ones? I am missing something on why both are offered. For a TR4. I would appreciate opinions.. thanks
 
86mm is standard size as I assume you know, I suppose if your fixated on stock you might want to stay there. But if the theory is more is better get the "big bore" pistons, they are usually a higher compression ratio as well. I got the 87mms for my 4A and it was a really sweat engine with nice power after that. 2nd gear from about 2500 to 4000 was especially nice.
 
For awhile you couldn't even get the 86mm sets, as everyone wanted the 87s. But I guess there are enough purists now that they are making the 86s again. Should give you just a bit better fuel mileage; and as noted a slightly lower compression ratio (think regular gas instead of premium).

Not everyone is a hot rodder /bcforum/images/%%GRAEMLIN_URL%%/grin.gif

Randall - with a set of 89mm pistons & liners just itching to go in an engine
 
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