Heads and cam?

[Ajfazio]

If you can find a set that aren't cracked.

Not if you do the work yourself. Cheap chinese heads are just that.

Here's where we differ. I like the asymmetric cam lobes with rapid ramp rates. Gets those valves opened faster and allows for more time to breath. Run the right oil and they hold up fine.

Yup, If the cam grinder says run this spring then run that spring.

If this is something your going to running on pump gas 9.5:1 is about as high as you want to go.
Tailor your stall to the application. If your building a race car then you want a higher stall to get off the line. For a street car you will want to lower the stall so your not running around with the converter slipping most of the time. On street cars with moderate gearing 1800-2200 is a better choice.

Run the 1.6's. You will get more lift without such an aggressive cam lobe.makes life easier on the lifters.

Something you have not mentioned is whether you're going to freshen up the bottom end. If you put all these go fast goodies on top of a tired bottom end it won't be long for this world. Remember, it came from a junk yard.

Hey I appreciate all the advice alot also i freshened up bottom end prior to putting this motor in the car a couple months ago only reason I’m tearing into the motor again is a wiped lobe on the stock cam and I figured I would do heads while I was at it

 

[Hipster]

If you can find a set that aren't cracked.

why would a new set be cracked, but thats another reason to stay away from used stuff.

Not if you do the work yourself. Cheap chinese heads are just that.

Not sure where you're going with that, not many have valve seat cutters, head surfacing, or guide fitting equipment, but yeah you can do a ghetto lap job etc., a little bowl blend etc. You forgo a big benefit as most oem heads are 2 angle seat if that. Personally I would source US castings but even that is getting more difficult.

Here's where we differ. I like the asymmetric cam lobes with rapid ramp rates. Gets those valves opened faster and allows for more time to breath. Run the right oil and they hold up fine.

Roller cams can handle more, running flat tappets, and I'll stay conservative instead of chasing the 5hp. claims. A Valvetrain instability issue is not going to care what oil you run. Lots of guys are still running flat tappets, not everybody is having issues. A decent head whose exhaust flows 80% of intake flow will almost make less power with asymmetrical lobe profiles. Extended duration on the exhaust side can over scavenge intake charge during overlap with a good exhaust port. Crappy exhaust flow +10 dur might help a bit. I'm **** about proper springs.

 

[Hipster]

Hey I appreciate all the advice alot also i freshened up bottom end prior to putting this motor in the car a couple months ago only reason I’m tearing into the motor again is a wiped lobe on the stock cam and I figured I would do heads while I was at it

wiped cam? planning a tear down and cleaning?

 

[Ajfazio]

wiped cam? planning a tear down and cleaning?

Not really sure just an excuse to tear it back apart planning on cleaning out everything just not in the budget for me to throw in a complete rotating assembly also why I preferably want to go flat tappet route , you recommend the 270 h for cam? I agree not really looking for sound here just as much power as I can squeeze out of this to get to that 300 mark and for heads any cost friendly brands you recommend?

 

[rebelyell]

since ya have little money in current JY motor, suggest start a new build with another JY motor: this time choose a roller block or, even better, a vortec L31 motor (eighth character in donor VIN is an "R")

* ya really NEED to pull the lower end apart to clean out any metal from failed cam-lifters.

**tip: it's a plus when ya can look at donor motor while still bolted in its OE vehicle --- you can look into its radiator too --- if there's only water in rad / block / heads, that's a tell-tale sign of overheating and, while trying to figure it all out, they didn't throw another $10 - $20 of antifreeze at it.

 

[Ajfazio]

wiped cam? planning a tear down and cleaning?

Not really sure just an excuse to tear it back apart planning on cleaning out everything just not in the budget for me to throw in a complete rotating assembly also why I preferably want to go flat tappet route , you recommend the 270 h for cam I agree not really looking for sound here just as much power as I can squeeze out of this to get to that 300 mark and for heads

 

[Ajfazio]

Not really sure just an excuse to tear it back apart planning on cleaning out everything just not in the budget for me to throw in a complete rotating assembly also why I preferably want to go flat tappet route , you recommend the 270 h for cam I agree not really looking for sound here just as much power as I can squeeze out of this to get to that 300 mark and for heads

It sent twice my b