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89 mm pistons and liners
- Thread starter JerryVV
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Jerry, I have not had any contact/experience with this conversion but I can tell you that thinner liners can get iffy.They will flex more than 87mm liners and if all is not perfect with the lip seals the cylinder wall can distort when the head is torqued.
If you are looking for HP look at the head.larger valves,porting and a good cam can give good results.If the balance job is good,5500 is a good redline and 130hp is not hard to get.
MD(mad dog)
If you are looking for HP look at the head.larger valves,porting and a good cam can give good results.If the balance job is good,5500 is a good redline and 130hp is not hard to get.
MD(mad dog)
Dan I have 87mm liners currently. I am asking for feedback from someone who has actually installed 89mm liners. Are yours 89 or 87mm? As for wall thickness I believe the suppliers have taken that into consideration. I know racers are using them but they remove the head and freshen things up on a regular basis. I don't want to do that every year if 89's will be a problem on the street.
MD, Yours is good advice too. Currently .090 off the head, a D Cam, 87mm (tired at this point)and some other things done as well. I need to replace the pistons and liners and I'd spring for the 89's if I can get some feedback on keeping the head sealed. The head will be reworked as you mentioned. It was last done many years ago. Not too sure about larger valves.
Thanks for the comments.
MD, Yours is good advice too. Currently .090 off the head, a D Cam, 87mm (tired at this point)and some other things done as well. I need to replace the pistons and liners and I'd spring for the 89's if I can get some feedback on keeping the head sealed. The head will be reworked as you mentioned. It was last done many years ago. Not too sure about larger valves.
Thanks for the comments.
Stock 4A would be 86mm. Mine are 86mm +.040 which works out to 87mm and they are bored 86mm sleeves. 89's are a more recent offering and I doubt they were available in the early 90's. My work dates to the early 80's for the sleeves and some hard miles since then. I'm using more oil than I should and will be replacing the pistons and sleeves soon.
I am guessing that you have 87mm which were available in the early 90's from almost all of the suppliers.
JVV
I am guessing that you have 87mm which were available in the early 90's from almost all of the suppliers.
JVV
I've got 89's in my 57. The PO purchased the kit on EBay back in 2000 for $800. I installed them about 5 years ago in my stock motor. I also re ground the crank, did the chain and gears, refurbished the head, and installed a street cam with lifters. I've run the motor several times but I'm still on blocks trying to fit the wings, doors, and lids. The pistons are Wiseco, the liners came from LA Sleeve, the head gasket was single layer steel. It sounds great and idles smoothly, but that's all I know.
tinman58
Jedi Knight
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Jerry
I have the 89mm installed in my three. There was a little increase in power. Was it worth $900 buck? Well that is for you to decide. I have had no problems with the 89 mm set that I am aware of. Yes I would get the 89mm if I had to do it over... It's only money!!!
I have the 89mm installed in my three. There was a little increase in power. Was it worth $900 buck? Well that is for you to decide. I have had no problems with the 89 mm set that I am aware of. Yes I would get the 89mm if I had to do it over... It's only money!!!
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I bought the 87mm "County" set and I am very pleased. Very smooth and the power is good.
I used Wellseal and copper figure 8's. I'd recommend always using copper. I put a mic on the copper and the steel, and the copper was noticeably thicker, giving a more "proud" fit at the head, and hopefully a better seal. Also, my old steel gaskets were badly corroded. Copper won't deteriorate like that.
Good luck.
I used Wellseal and copper figure 8's. I'd recommend always using copper. I put a mic on the copper and the steel, and the copper was noticeably thicker, giving a more "proud" fit at the head, and hopefully a better seal. Also, my old steel gaskets were badly corroded. Copper won't deteriorate like that.
Good luck.
IMO there's no reason not to use a standard copper/asbestos substitute gasket as long as the pistons don't hit it.
Best thing to do is ask Moss about this. Pete Cox, who is quality control at Moss UK recommended the kit to me and quoted a significant increase in torque as a benefit. I being a coward and cheapskate went with 87mm pistons, but there's no doubt Moss are confident, so why not ask them if they do a suitable gasket to go with the 89s.
Ash
Best thing to do is ask Moss about this. Pete Cox, who is quality control at Moss UK recommended the kit to me and quoted a significant increase in torque as a benefit. I being a coward and cheapskate went with 87mm pistons, but there's no doubt Moss are confident, so why not ask them if they do a suitable gasket to go with the 89s.
Ash