how bad is this and how much performance am i losing?

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rigger3006

rigger3006

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so ive had these 302 heads for 5 years now, been on 2 different motors and today i finally noticed(ya i know!) that when the PO put in 340 springs he didnt use different exhaust valve,just removed rotators and installed springs,so the exhaust spring is far more compressed than intake.any thoughts how bad this is in relation to performance?
 
how the heck would that run? No way to set the slack!
I get it.....
/
 
Last edited:
oldkimmer said:
Maybe he knows something the rest of us don’t. I’m thinking that can’t be good. Kim
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Oh im sure its not a good thing, just looking for opinions, of course i know its not right.just wondering how it may affect my performance
 
What's the lift in the cam? We measured this very thing on my sons engine, and ran into coil bind with our .444/.466 lift cam.
 
Ive ran the 340 cam, 474/280 & 484/ 284.theyre being yanked and put up for sale.ive got a set of j's and set of 308s to use
 
292 in yet? When you do please let us know!:popcorn: I really want to find out how it compares to what you removed. I currently run the 280 and not too impressed. Will go 292 and accomodate rear gear converter intake etc to make it run!! Tune tune tune as well.
 
We had a guy do that, thank God we check the heads. Coil bind at almost zero lift....

I can't believe it's working......

How are the locks (keepers) even working?
 
Sorry I didn't take pics, the exhaust spring is now shorter than the intake, did not take much lift before it was in coil bind.
 
Without coil bind, your not losing any HP because the valve lift is not affected. If your not rapping to point of valve float, there is likely no difference. coil bind would be very pronounced as in bent pushrods as that is the weakest link, or possibly breaking through the stamped rocker pocket.
 
QuickDart360 said:
292 in yet? When you do please let us know!:popcorn: I really want to find out how it compares to what you removed. I currently run the 280 and not too impressed. Will go 292 and accomodate rear gear converter intake etc to make it run!! Tune tune tune as well.
Click to expand...
not yet, still 2 ft of snow in front of garage,supposed to warm up today.now to mess up my normal life my wifes uncle offered her a free built up 440, we just have to travel 10 hrs and pull it,then decide what to do with it, ie sell, put in my demon or her duster,or find a new project for it,decisions decisions!
 
I'd say if it was bad, you would have broke it by now.
Granted this with mild cams and usage, but I will just swap retainers and leave the valves. Especially if it's on the car and the cam is mild. I never measured, but I think the overall difference is less than .100" between the rotator valve grooves and the non-rotator grooves. Biggest cam I've done that with is about .480 advertised lift, so with pushrod angles it's less than .460 at the valve.
 
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