What lash to run on a 5.0 HO cam?

[Brantley]

I hate hydraulic lifters so much that I am tossing them and putting in some solid crower rollers in my 351w. I am running a stock 5.0 HO cam right now.. just wondering what would be a good place for starting lash on the intake and exhaust? This is a turbo engine, so the exhaust side will be seeing some heat.

 

[Modular2v]

well....if you are going to solid rollers you are going to have to change to a solid roller camshaft! Hydraulic is not that hard! Set it to right b4 0lash

 

[dtlionsfan]

Put each piston at 20* BTDC then tighten intake and exhaust down until tight when the valves touch the piston.Then torque to 20 pds. foot and move on to next set.































Just kidding.I guess zero lash? Never tried solids on a hydro roller.

 

[wicked84gt350]

He was right you need a solid roller cam but lash should be .020 and that is the space between the rod an rocker But get ready to have to be pulling valve covers and adjusting rocker every 5-10 thousnad miles. Solid is really for more race appaclitions were you have lots of lift and duration and need to prevent lifter pump up and valve float it not really for the street.

 

[Brantley]

I was thinking in the .015 to .020 range for lash.. yes, I am fully aware of what lash is, and I also know I'll have to adjust them. This is a twin turbo build that is rather expiramental before I build a real engine with real parts. It is very unlikely that I will be putting loads of miles on this car. I will probably drive it on the street 1 or 2 days a week and hit the track once a week. Frequent adjustment is the least of my worries.

Any why would it matter? this was a roller cam to begin with, I can't imagine that the cam would know the difference between solids and hydraulic roller lifters if the solids are setup correctly, but I could be wrong. I guess we're gonna find out, because I'm not spending money on a cam right now.

 

[Brantley]

also, "right before 0 lash" is definitely not specific enough.. give me a number in thousandths.

 

[Modular2v]

I was thinking in the .015 to .020 range for lash.. yes, I am fully aware of what lash is, and I also know I'll have to adjust them. This is a twin turbo build that is rather expiramental before I build a real engine with real parts. It is very unlikely that I will be putting loads of miles on this car. I will probably drive it on the street 1 or 2 days a week and hit the track once a week. Frequent adjustment is the least of my worries.

Any why would it matter? this was a roller cam to begin with, I can't imagine that the cam would know the difference between solids and hydraulic roller lifters if the solids are setup correctly, but I could be wrong. I guess we're gonna find out, because I'm not spending money on a cam right now.

A solid roller roller puts ALOT more pressure on the cam than the hydra will....do a solid roller setup on a hyd roller cam and you will chew your cam lobes up because the cam cant is not hardened enough for the pressure......this also goes with valvesprings.....you will need ALOT more spring pressure with a solid roller setup. This is why most people stay hyd roller, it is 500-1000$ to convert to solid roller. For what you described that u are using the car for, you have no need to go to solid roller and i see it as a waste of money. Unless you plan on spinning the car to 8000rpms the hyd rollers will be fine, and if you spin it 8k you better have the proper H/C/I to do it, the money piles up quickly!

 

[Modular2v]

also, "right before 0 lash" is definitely not specific enough.. give me a number in thousandths.

by the way are you using pedistol or stud type rocker mounts(ill assume stud) if you are using pedistol though, simply torque them to 25 ft/lbs and be done, the fulcrum does everything for you. O lash as in when the roller tip is touching the valve tip but you can still move the rocker back and forth a little

 

[vikingpower]

solid lifters are actually 'easier' on the cam than hydraulic lifters since they have a lot less mass. As long as you run the correct lash it should be fine. Look up some lash specs for 'smallish' S/B roller cams and use them. You'll be dissapointed though, the HO cam is puny even for a mild 302.

 

[Modular2v]

solid lifters are actually 'easier' on the cam than hydraulic lifters since they have a lot less mass. As long as you run the correct lash it should be fine. Look up some lash specs for 'smallish' S/B roller cams and use them. You'll be dissapointed though, the HO cam is puny even for a mild 302.

so you are saying that a solid lifter with no give at all is going to be easier than a lifter that gives on valvtrain parts ? Call me crazy but that just does not make sense to me at all..... Yeah the HO cam is puny for sure!

 

[Brantley]

Thanks for the input.. I di dmore research and decided to get a solid roller cam and just do it the right way. It's a 244/250 @ 0.050; .570 lift; 112 LSA. Should turn out to be a fairly decent turbo cam.. moreso than the 5.0 HO, anyway.

Thanks for the input.