Small block conversions using a 116mm rod.

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YAMLAM
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apart from a RB20,are there any other conversion pistons i can use in a small block using a 116mm rod ?
ie. could you use a susuki ts 185 piston and a 2mm packer,or would the port timings be way out ?
thanks
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corrado
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You can get Mugello and Imola kits to suit TV rod.
Knowledge
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TS185 piston and a packing plate is a good option. The 116mm rod helps tame the inlet timing on the ali barrelled SR185.
Martin
dirtyhandslopez
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Finally getting together the TS pistoned TV I am putting together. Tell you what, cutting a packer out of an ali road sign is proving to be quite a pain. Start cutting on no. 2 today...
Wish I had ordered a few of different thicknesses :evil:
Thank you to the city of Richmond for the plate ali. :biggrin:
That's not going anywhere...
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mawso
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TS185 piston, TV2 barrel and 116mm rodded AF crankwebs, that's my set up and it's lovely!
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Stokie
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MecEur GP crank with TV rod, Suzuki TS185ER piston, SR190 barrel, no packing plate required with my Spanish casings.
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dirtyhandslopez wrote:Tell you what, cutting a packer out of an ali road sign is proving to be quite a pain. Start cutting on no. 2 today...
Wish I had ordered a few of different thicknesses
I pick-up a sheet of ali, thicker than I require, perhaps 5mm. I then lay an old gasket on the ali plate and spray over it with a can of paint. When the paint is dry, peel the old gasket off and then cut away all the ali that is painted. You can leave it "over-sized" on the outside, especially around the transfers.

Now slip the spacer plate over the barrel spigot and put the barrel on the crankcase with the piston on the end of the conrod. Turn the crank so the piston is at BDc, and measure how much the crown of the piston is above the bottom of the transfer ports (say 3.2mm). Now remove 3.2mm from the bottom of the barrel and seal it with silicone instead of using a traditional gasket.

The advantage of this, especially on the SR barrel, is that you will be able to widen the base of the transfers significantly now you have abandoned the traditional base gasket. You also don't need to have the correct thickness of ali plate to make it work. You'll save yourself a fortune, once you've bought the lathe. ;)
Martin
dirtyhandslopez
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I've got a poor mans lathe; die grinder and assorted burrs and polishers, a drill, a belt sander, and a piece of plate glass with some 1000 grit on it :P
Finally got a second spacer cut. I had based the first spacer on a base gasket, used machinist ink, etc, but halfway into it sussed the base gasket wasn't big enough to cover the TV barrel gasket surface :cry:
Opened the exhaust to about 43mm and raised it just a hair. Polished and flowed all the ports, stuck a 20mm and a KBA clubman on it and kicked it to life(3 kicks).
Loads of torque, smooth, quiet, and feels like it's going to be a quick'un.
1.44mm squish, no head gasket, one base gasket between barrel and packer, no gasket between packer and case. Haven't checked compression yet, but it feels like it's about 131.49psi ;)
Time to put some miles on it before sending it out...
That's not going anywhere...
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