Technical Powervalves

Can anyone tell me what size powervalve this is? 2.5? 8.5? Some are easier to read than others...

 

I say 8.5
Maybe remover check /look @ spring
Hand Vac pump is good to have
Cheap one's from Harbor Freight Ect.

 

Its a 3x2 setup....trying to decide if they knew what they were doing or not....its a secondary carb so 2.5 would be good, 8.5 means I have to get smaller ones and likely rejet the secondary carbs... the new pv's are waaay easier to read than these old ones, p.o. said it never ran quite right...no idea if he knew what he was doing or not either

 

I just checked 2.5 , Little to no resistance on the spring when you push it with your thumb compared to a 5.5 and a 8.5

 

Ill pull it and feel the spring, thanks! I have an 8.5 modern one around here for comparison im sure

 

3x2 using 2.5's is as close to right as you can get, in many cases.

Many original singles run a 7.5.

7.5 ÷ 3 = 2.5.

That has always been where I start, and often stop.

 

I was always told to run a bigger one on the primary carb, 2.5s on the secondary carbs...since you run on just the primary most of the time

 

Thinking 2.5, has a good bit less spring tension than the others, also...I think I discovered why it never ran right haha they were using the dual vacuum early distributor.... I have a mech adv mallory and a single vac advance later ford. Will likely run the single vac advance version

 

I never do that.

 

Ill take your word for it! 3x2.5 coming up!