Johnson "70mod"

[hupiveneilija]

Here are couple of pictures for powerhead. I have also weighted rods and pistons, they are within .5grams the same. Crankshaft and flywheel are on the way.

[LittleCharger]

Are you going to blend the exhaust ports in the pic it looks like some mismatch still between block and sleeve.

will be interesting to see how those heads work. You may need head studs if the compression is real high as then tend to blow head gaskets without them

[hupiveneilija]

They are matched, picture may lie. I dont know what psi will be but head maker did it so that the compressionratio is aprx. 7.2:1, i think, with stock ex.port. Since I have raised the ports its lower now.
edit; I think he said that stock comp ratio was 5.9:1.

[filthy phill]

what is that metal wall behind the exhaust bridge ?
not seen this before, my block definitely dont have a wall behind the exhaust port.

did you put this there ?

[LittleCharger]

what is that metal wall behind the exhaust bridge ?
not seen this before, my block definitely dont have a wall behind the exhaust port.

did you put this there ?

Stock

[filthy phill]

what ?
are you saying this is normal for the 56 bridgeports to have this thick dividing wall in the exhaust behind the liner ?.

so this means the blocks used for bridgeports are not the same as oval port and sst60 motors.

[PPRINT]

Looking really nice.

Did you machine those stacks? Or were they off-the-shelf item?


Rob


Sent from my SAMSUNG-SM-G900A using Tapatalk

[hupiveneilija]

Hi!
Off the shelf, made for dellorto 40mm.

[ferdthe4]

very interested to see if the carb stacks and slight enlargement helps much

[hupiveneilija]

To me it seems that throttle response is better everywhere. These should be little shorter to gain more up top. But, we have had very hot here for a long time and it still goes like before on cooler days despite putting one step smaller mainjet!

-J-