Author Topic: MAP H-beams  (Read 442 times)

Offline A10 Tim

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MAP H-beams
« on: 17.06. 2018 10:24 »
Hi All,
       I've purchased a pair of steel H-beams from MAP for the rebuild of my 1960 A10.
And I found them to be approximately 30 thou longer than the original rods.
Have any of you knowledgeable chaps fitted these steel H-beams and had any problems with them being slightly longer.
Many thanks for any info.
                                   Tim.

Offline coater87

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Re: MAP H-beams
« Reply #1 on: 17.06. 2018 16:49 »
 I fitted the map rods.

 I was aware of this, but my pistons did not pop above the cylinder lip, the valves certainly did not hit the crowns.

 I suppose it will come down to each individual motor, and what has been done to it over the years.

 Lee
Central Wisconsin in the U.S.

Online RichardL

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Re: MAP H-beams
« Reply #2 on: 17.06. 2018 16:57 »
This is one of those, "others will know better than I" topics, nevertheless, I have thoughts. I went out and measured all my old copper head gaskets and the thinnest was 0.032" thick. So, it seems that if your gasket is clear of the bore, the extra 0.030" length of the rod would not be a problem. Of course, you would need to double-check this with the pistons at TDC and the head off.

Richard L.
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Online muskrat

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Re: MAP H-beams
« Reply #3 on: 17.06. 2018 20:35 »
G'day Tim.
I doubt you will have any problem. I have R&R alloy rods of the same length and with 10.5:1 pistons and and 357 cam have no clearance problems.
You may need to balance the crank due to any weight difference of the rods.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7

Offline A10 Tim

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Re: MAP H-beams
« Reply #4 on: 24.06. 2018 07:13 »
Hi Muskrat,RichardL and lee.
Thanks for the advice, I'm going ahead with the MAP rods.
I found that SRM can supply a thicker head gasket if piston were to clip the head.
Although that would defeat the object of the rods.
I'll keep you updated when I have fitted the barrels.
Thanks again
                  Tim

Online KiwiGF

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Re: MAP H-beams
« Reply #5 on: 24.06. 2018 11:54 »
Hi Muskrat,RichardL and lee.
Thanks for the advice, I'm going ahead with the MAP rods.
I found that SRM can supply a thicker head gasket if piston were to clip the head.
Although that would defeat the object of the rods.
I'll keep you updated when I have fitted the barrels.
Thanks again
                  Tim

Just a thought, you want to be sure there is no wear lip in the barrel as the rings will probably hit it if so!
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Online berger

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Re: MAP H-beams
« Reply #6 on: 24.06. 2018 12:14 »
now that is very very good advice, my mate rebuilt his trump after I told him to get rid of the lip in the bottom of barrel, his idea was the rings would close up EH!! , I said you what at that speed *whistle* he went ahead and broke the oil rings straight away ;)