Need lessons on how to talk 'machine shop'.

[typ4]

glad you explained that cause I dont have the time, well explained.

 

[ocnorb]

woulda been cheaper to haul it up here

Trust me, if I had the time off to do that I would!!

I've made it to Portland in 10 hours on my bike! Funny thing is that my truck must have spent some time up there before. When I was fixing the heater door I found a flyer to a church dance in Oregon with a little map on how to get there.

The block will get stripped down and taken to the machine shop. Its gonna get decked, checked and honed (at the very least) the heads done, Comp 910s, valve job and the works...

I found a shop just down the road from my house and the guy has 1. a great attitude 2. a great reputation with local builders and 3. doesn't up-charge for diesel stuff. I think they are looking for some work too, cause he told me he could turn my heads around in a few hours on Friday. Couldn't get off work though.

Hope that I can re-use my .030 over pistons, but I am thinking about having them shaved. (Especially if the block gets decked.)

How far can we safely go on the pistons?

 

[ocnorb]

when you talk valve springs, you need to be aware of several things. Install hight and coil bind are verry important in a high lift system. The IDI is not a high lift engine so spring rate is more important. The stock springs are about 85lbs seat pressure closed and the 910 is rated a 92lbs Now the closed pressure can be ajusted by the installed Hight. but you can only shim so far or you risk coil bind. Knowing the range of opperation of your valve train (the valve lift) you can adjust the shims to get the closed pressure you want and the open pressure you need to keep the valves from floating. The spring rate per inch is what changes the open pressure. The comp 910 spring is a good upgrade from stock, You can install them in the IDI without checking anything and they will be fine. The stock install hight is right in the sweet spot on the 910's range. The PSD guys like to shim them to 1.70 when they run over 50 psi boost. The 910 springs can handle .500 lift when installed at 1.85 giving a 92lb closed and 300lbs open at 1.35. The Typ4 cam lift is .392 (from my specs given to me by Russ) so we can shim up the springs to increase pressure closed and still be safe. It is posible to calculate open pressure if you use some math. Its better to use a spring machine to see the rate. I have done some looking and found one other spring that is close to the 910 its the comp 926 its 108lbs at 1.80 and 317lbs at 1.30 the 926 has an OD of 1.475 (The stock spring is 1.40 OD) and a rate of 418lbs per inch. I dont think it is needed because its not a big enuff increase, I was thinkin about using them but have changed my mind I will be using the 910's instead. I will be shimming to about 1.80 and using a j2 cam. Just thought I would put my .02 in

Thanks!

I did a bit of research on this- there are some great write ups in the PS world. I wondered if our trucks would even need any shims. Almost popped for the valve height micrometer, but our budget has it limits.