vipvegas

iTrader: (13)

I brought the rockers to my builder with the trunion upgrade installed. Nothing has changed in my 241 heads, same valves and dual gold springs as before, rod legnth changed a little from 7.4 to 7.3 but thats it. Why would the builder have to put another 1/4 inch of threads on the stock rocker arm bolts to get them to mount properly. This doesnt make since the spring height or rocker stand has not changed in anyway. This is not making since to me.. Anyone else experience this?

vettenuts

iTrader: (4)

Hard to believe that the trunnion is that much larger in diameter than the stock setup. If the bolts tightened down OK (didn't bottom) you are likely alright. What grade bolts did he use? Did he give you back the stock ones? Is there a flat side on the new trunnion and if so did he mount it up?

vipvegas

iTrader: (13)

he used the stock bolts but added 1/4 inch threads to each bolt. I dont get it.. There is a recessed area for the head of the bolt to sit in. I have an extra trunion and a stocker so maybe Ill measure them up.

outlawnova

iTrader: (4)

Sounds like he changed the thread diameter not length

vipvegas

iTrader: (13)

definately added another 1/4 of thread where the thread of the factory bolts end going toward the head of the bolt.

printmanjackson

iTrader: (1)

can you post a pic so we can get a better idea?

vettenuts

iTrader: (4)

That would indicate the trunnions sit lower than stock and the bolts were running out of thread. Hard to believe that one especially when the rockers are sitting in the rocker support pad

69LT1Bird

iTrader: (1)

Make sure he is installing them correctly. I think (not sure) that you can rotate the new trunnion 360* unlike the factory. Maybe it is upside down. Just a thought.

vipvegas

iTrader: (13)

Im still using the stock stands, really nothing has changed besides the trunion. Here is a picture of the bolt

69LT1Bird

iTrader: (1)

How about a picture of both sides of the trunnion? One side is recessed, not sure on the other side.

vipvegas

iTrader: (13)

Wow now I see the reason, if you match both trunion at the base where they sit in the pedestal. Then examine where the retaining bolt head would sit. It sits 1/8-1/4 higher in the stock bolt then the recessed area in the Comp trunion. So basically when using the comp's the stock bolt will work but you will have a portion of the non threaded part of the bolt in the head if you do not put some more threads there, as the bolt now goes 1/4 or so more into the mounting hole in the head. I was suprised it didnt bottom out and there was enough leadway for the extra bolt legnth. I talked to builder and this is exact reason he wanted to make sure that there were as many threads as could be used to maximize the strength and hold of the bolt inside the head. If you can get 4 more threads in to secure it to the block why not. So everyone who did the upgrade could use more threads or new bolts as a safety measure is what Im seeing.

69LT1Bird

iTrader: (1)

Did he HAVE to run a die over the bolt threads or did he THINK he had to. This is the first time anyone has mentioned a bolt length issue. Put a pair of calipers on both and see what the actual thickness is where the bolt goes.

At 22 lb ft, the increase in clamp force from a couple extra threads won't do anything.

vipvegas

iTrader: (13)

Will check them with calipers at the shop a little later today. This guy is very picky and checks everything. I dont see him overlooking it if it was needed or doing it if it wasnt. I will post caliper specs later

VIPRETR2

iTrader: (63)

Harland Sharp ships shorter bolts with their upgrade, maybe this is part of the reason. I think it also had to do with stock bolts sticking into head castings that had been ported. Either way, if the bolts you have work, use them. If they bottom out or project into the ports you can buy shorter bolts from Edelbrock, I don't know if Harland Sharp sells their bolts seperately. Good luck,

Larry

printmanjackson

iTrader: (1)

I'm really suprised that the instructions never mention to check this.

bluethunder364

iTrader: (5)

I did the Harlan Sharp upgrade on my L92's. They do come with shorter bolts
They have worked well thus far for me. Sure the Comp version is just as good

1MtnGoat

I just got back from the shop where I was hopefully installing my rocker arms upgraded with Comp Cams trunions. The stock bolts are short about 3/16" on threads. They sit in the trunions deeper so need more threads. I called Comps cams help line but was told the guy who knows the answers works from 9-5 CT. So will try tomorrow. Will the stock bolts loose strength if we cut more threads? I believe the stock bolts have rolled threads not cut. My thinking is that cutting more threads in the "middle" of the bolt will weaken the bolt where the most stress is where it screws into the head. I think we need a spacer. I will see what they say in the morning.

69LT1Bird

iTrader: (1)

If comp says you need new bolts, they should have their ***** cut off for sending out a product like that without the new bolts or at least documentation to explain it to the customer.

printmanjackson

iTrader: (1)

surely this is not the first time for this. Let's see what CC says tomorrow before we bring out the pitch forks and torches.

vipvegas

iTrader: (13)

I agree on the pitch forks. But Im glad my builder found this either way. To me I just like things perfect and something like that isnt right, if there is a need for more bolt why wouldnt they supply with the kit?? I got everything bolted down tonight and all went well and now threads sit to the top of head. Looks great and makes me feel like its perfect...