Rocker arm to valve spring retainer interference
Rocker arm to valve spring retainer interference Just hit a major snag in my build. My stock rocker arms with trunnion upgrade have major interference with my valve spring retainers. I am using World Product Warhawk heads that have 1.550" double springs and a 1.950" installed height. The heads are off the engine now so I loosely bolted the rocker arm using the stock pedestal and the tip of the rocker was at least 1/8" off of the valve tip because the rocker body was hitting the edge of the spring retainer. I can take pictures if needed to show this better. I am using a Comp Cams LSr cam grind with .610"/.617" lift at 1.7 ratio. I planned on checking pushrod length and replacing the pushrods no matter what.
As far as I can tell I have the following options:
1. Shim the pedestal to raise the rocker and clear the spring retainer. I don't know if this is a valid option strengthwise. I also know I would have to check the wipe pattern and use longer pushrods if I do this.
2. Get different springs and retainers (Comp cams has one with a 1.320" dia and 1.835" installed height that is made to go with the cam. I don't know if this would give me the clearance I need or not with the stock rockers. I know I would need to shim the springs .115" and also I would need spring locators due to the smaller size.
3. Get new rocker arms like the Yella Terra that have adjustable mounts. Thsi seems pretty straightforward, but I still don't know if they will clear the 1.550" springs.
Any help or ideas you guy can give is appreciated. If you have negative comments about my choice of heads, please move on.
As far as I can tell I have the following options:
1. Shim the pedestal to raise the rocker and clear the spring retainer. I don't know if this is a valid option strengthwise. I also know I would have to check the wipe pattern and use longer pushrods if I do this.
2. Get different springs and retainers (Comp cams has one with a 1.320" dia and 1.835" installed height that is made to go with the cam. I don't know if this would give me the clearance I need or not with the stock rockers. I know I would need to shim the springs .115" and also I would need spring locators due to the smaller size.
3. Get new rocker arms like the Yella Terra that have adjustable mounts. Thsi seems pretty straightforward, but I still don't know if they will clear the 1.550" springs.
Any help or ideas you guy can give is appreciated. If you have negative comments about my choice of heads, please move on.
Those heads are set up for a solid roller cam. That usually means longer valve stems for greater valve lift. To maintain proper rocker arm geometry, you need to raise the rocker arms, and use longer push rods.
Here are your spring specs: 1.550": 200 lbs. @ 1.900", 480 lbs. @ 1.200", coil bind @ 1.150", max lift MAX LIFT @ .700"
Those spring rates require quality aftermarket rocker arms.
If you're going to use a solid roller cam, update the rest of the parts to match. If you're using hydrailic lifters, change the springs to match, and then shim the rocker arms.
Here are your spring specs: 1.550": 200 lbs. @ 1.900", 480 lbs. @ 1.200", coil bind @ 1.150", max lift MAX LIFT @ .700"
Those spring rates require quality aftermarket rocker arms.
If you're going to use a solid roller cam, update the rest of the parts to match. If you're using hydrailic lifters, change the springs to match, and then shim the rocker arms.
Thanks Bob, I saw that about the solid roller cam, but the complementary Comp Cams Springs for my hydraulic cam are every similar in rates;
.675" max lift
159 lbs on the seat
448 lbs at .675" lift
with my cam
420lbs@ .610" lift
423lbs @ .617"lift
comparing to my current springs
200 lbs on the seat
480 lbs at .700" lift
with my cam
444lbs@ .610 lift
447lb@ .617 lift
Does 20-25lbs really make a difference between hydraulic and solid?
I will change the springs if I have to, but I really don't see the need at this point unless it gives me the rocker clearance I need.
When you say change the spring and shim the rocker arms, how would you shim the rocker arms? Do you mean an aftermarket arm or the OEM?
.675" max lift
159 lbs on the seat
448 lbs at .675" lift
with my cam
420lbs@ .610" lift
423lbs @ .617"lift
comparing to my current springs
200 lbs on the seat
480 lbs at .700" lift
with my cam
444lbs@ .610 lift
447lb@ .617 lift
Does 20-25lbs really make a difference between hydraulic and solid?
I will change the springs if I have to, but I really don't see the need at this point unless it gives me the rocker clearance I need.
When you say change the spring and shim the rocker arms, how would you shim the rocker arms? Do you mean an aftermarket arm or the OEM?
That's too much spring for the stock rockers. You don't need that much spring... and you only want as much spring as necessary, not more as it can rob power and cause premature wear.
If you intend to use, the open spring pressure isn't what concerns me. It's the seat pressure. You'll need to upgrade to a lifter that can withstand that without bleeding down. Morel or Johnson would be my pick there.
If you intend to use, the open spring pressure isn't what concerns me. It's the seat pressure. You'll need to upgrade to a lifter that can withstand that without bleeding down. Morel or Johnson would be my pick there.
I spoke to Bill Mitchell/The Engine Shop (World products heads), Yella Terra and Comp Cams. Based on those discussions and comments on this thread, I am going with the 26926TS-Kit Comp spring kit and the Yella Terra YT6638 Rocker arms. I will have to shim the springs to get the right installed height and may have to grind on the head/valve cover for rocker clearance. These heads I bought, which seemed like such a bargain are now bleeding me dry. This engine better run like a bear when I am done.
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Of the three you spoke with I would not listen to anyone of them.
Sounds like you have the wrong parts and are trying to fix it with stuff that will work but is not the best choice of parts
No way would I trust those rockers with anywhere near that much spring.
Custom PAC spring kit would be you best option. Depending on your valve length you may need shorter valves or buy a set of $1500 shaft rockers.
Tim
Sounds like you have the wrong parts and are trying to fix it with stuff that will work but is not the best choice of parts
No way would I trust those rockers with anywhere near that much spring.
Custom PAC spring kit would be you best option. Depending on your valve length you may need shorter valves or buy a set of $1500 shaft rockers.
Tim
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Verdad Gallardo Worl Product heads are good, but not stellar. You bought the wrong parts for your application, and are now spending more money trying to get them to work properly. Been there, done that.
You should consider replacing the valves with shorter stems. I'm not sure what clearances are with the YT rockers, but after you shim them up for the longer valves, you might have trouble with valve cover interferance. And you'll need longer custom made push rods.
You might consider selling what you have, and starting over. In the long run it sometimes works out cheaper and easier that way.
You should consider replacing the valves with shorter stems. I'm not sure what clearances are with the YT rockers, but after you shim them up for the longer valves, you might have trouble with valve cover interferance. And you'll need longer custom made push rods.
You might consider selling what you have, and starting over. In the long run it sometimes works out cheaper and easier that way.
Well, those of you who said I should just cut my losses and start over are prophetic. I bought the Yella Terras and they didn't even come close to working. They ran into the inside valve cover rail. I also bought the Comp Cam springs and they let me physically bolt on the stock rockers, but the wipe pattern on the top of the valve was way off. The only way to make it work was with a 1/4" shim under the rocker stands which is way too much for me to be comfortable with. Sooo, I am going to get another set of heads, probably one of the ported sets from Texas Speed. I should be able to return the Yella Terras and the Comp Spring kit and I am putting the Warhawk heads up for sale for cheap. I know some people have made them work, just not me. Again, thank you for all the input. I was being a stubborn a$$, but I finally saw the light.
Texas Speed PRC Stage 2.5 5.3 heads are on order. Nice power in the low and mid range good power up top. Works with my stock rockers and cam choice. Reasonable price. Good reviews from other posts on this site.