madkaw

I’d help you out but your still 4 hours away , plus I think I forgot how to work on carbs now :0 now if you go Megasquirt I’ll set you up !! Youll need to sell off the Weber’s to pay for EFI , but won’t regret it

You will have to pull the dash

I’ll repeat what I said on FB - that panel is worth saving

No current dyno runs. With SU’s I did 155 with my L24 . I plan on taking my current set up to the dyno- but other than EFI , no changes , so I think similar results .

My 490 ISKY pulls hard to 7000, but I can’t be specific about the cam timing . My head is shaved over 50 thou without using shims and have my cam advanced 8 degrees. I didn’t degree after the last 20 thou shave , but with 30 thou cut the cam almost cam in too late . The other factor was I went from triples to n42 injection ( Megasquirt) . If that graph was accurate then it would seem that it wouldn’t be as user friendly on the street at low rpms. My ISKY just puts along at 1500 rom in fourth around town without a jug

My understanding from Steve Bonk- who sells these - if I understood him , was that the shorter duration helped with clearance issues even with its high lift . But don’t quote on me on this

Duration 315?

I thought the DP cam had a shorter duration which in turn would not be making power later than the Isky- but I’m guessing here. So the higher lift is killing the low end?

35$ hall sensor , DIY flywheel drilling- out of sight

Then the valve was defective if I understand the way it works correctly. And I believe the vent line goes to the valve - not the crank breather tube. Valid point about vent line being higher than tank for sure .

Actually - the way that valve works there is no direct air route from the PCV to the tank. What opens the vent valve is pressure build up from the tank. You can test the valve by trying to suck air thru it.

On my 71 , I ran the vent fitting on my Tank Inc in flex line all the way up front to the original vent valve on the fender .

Should of went high impedance injectors IMHO- would have mounted in with a Pallnet fuel rail easy. I know someone who has the dizzy if you need it. You are going like the MS once you get it going. Some good help available here

Damper Doc did mine years ago and guaranteed like 8 grand rpm and 400lbs torque . I’ve had no issues and it was about the same price.

Page 2 has some good discussion.

Might need to elaborate on this statement

How much for their rebuild?

Hell- if you willing to spend that money , buy one of Datsun Works heads and something truly special

I’ll give a nod to getting help from Chickenman and kits from Softopz to get you started. I think the GM coolant sensor will thread into the later thermostat housings that have 4 holes.

Damn- I thought my ISKY 490 was big league need to up my game !

This is why I don’t like MSA . POS product that doesn’t fit and they keep selling it. It was not machined properly PERIOD . Sent one back for the same reason - too small. There isn’t variances in tolerances on our engines - it’s just a bad product

Have you not checked the MS web site ?

It isn’t easy to do ( degree a cam) for most though. Maybe that small bit of advance built into the cam is for that crowd that doesn’t . I’d almost advise against trying if you don’t feel confident about the process. If somehow the user retarded the cam drastically , they could smack valves . On the other hand , if you use the stock sprocket and set it up just like stock , it’s unlikely you will have any issues or be far enough off to negatively affect HP by that much. I have been considering a whole tooth on my build , but it starts getting pretty hairy then😳

Might have left some HP off the chart. Timing is important especially comparing apples to apples . That’s all part of tuning !