67rschev

....... Just getting together a parts order , and i had a few questions for you motor guys . First can the exhaust valves be reground , the three i have that i have that are not bent are starting to show a small amount of dimpling on the face . With the price of these pieces i would like to try to use them . Second is what is an acceptable amount to have surfaced off the head . I will be running late 10.2 -1 pistons , and rules state no more than a ratio of 10.5 - 1 .
Thanks

Spidey944

valves can be reground, I do it all the time at our machine shop here while rebuilding heads. The 944 head IIRC has a dimple on the head surface, and that is your machine mark. If you shave it past the dimple, the head is now beyond spec. I have a head on my bench at home that I can check to be sure and give you an exact location of where it is if you need it later. Again, this is what I remember reading on these heads, and hope I am not way off here.

If you do grind the valves, have it done at a machine shop, and it should cost you very little. but you will also want to regrind the seats on the head to match your fresh grind on the valves. If someone brings me a bare head, and valves, and just wants a re-grind done and no assembly, I'd imagine the bill would be around 50.00 bucks. And the cleaner the parts are the better, as dirty stuff is a pain for us to work with. Even if the head is brought in complete and dirty, we clean, bead blast the whole head, clean some more, gind the valves and seats, all for 150 bucks. And it looks like new. HTH & GL.

Mike C.

I had mine all reground and they had around 170K miles on them.

67rschev

Thanks , i wasnt sure if there was a Stilite coating or not on theses valves .

I dont see the 'dimple' you are talking about , but i was pretty sure this is a virgin head . A pic or a location would be great .The surface is flat and true and really nice shape , so maybe it had been worked . I was just wonder max cut on these heads , as im looking to be in the 10.5 ratio with late pistons . I will be cutting the seats myself with a NewWay .

special tool

.012-.015

Put 30 degrees on the back of the valves.

67rschev

Thanks all for the info ....
Change of plan , as this morning i realized i dont have the proper fitting pilot shaft for the valve seat cutting . Thats ok , as i wanted to have one guide installed at a machine shop any way . So any one know of a good shop in the Denver area ? Will probably use F+M Performance as they have done some nice work for us before .
Another Question , How much of a cut can i do with the stock early pistons ? What about an angle cut ?

svochuck

All good questions and answers ... Here is some more thoughts on head work in 944-spec. 944-spec does not allow offset timing woodruff keys so if you shave the head too much you risk throwing off your valve timing. If you want a compression ratio close to 10.5:1 and you have 88 pistons talk to Eric Kuhns . He shaved a head , had 88 pistons, but installed a "turbo" head gasket. On the whistler i tested his car at 9.8 :1 . so if your going for 10.5 :1 you better start looking for a non "turbo" head gasket...
From what I have seen Don't worry about shaving a virgin head to bump up the compression ratio it causes other problems and does not gain much if anything on our stock engines. just true it up with a simple valve job. Other items are more restrictive.

DartAuto.com gives us a discount and $500 per weekend in sponsorship $ . so please try him out for parts needs.

If you can get out to our pueblo race in march we have a comp school planned and you would be the 16th 944-spec !

67rschev

Hey Chuck
I just got your PM , and no worries . I look forward to getting with you guys and am exicted to see what its gonna take to field one of these cars . Im in the prosess of building a motor , and i would like to keep it within the rules for your spec class . Ive just finished up the suspension upgrades for scca e stock solo but i want to do more . The scca rules are very tight as to what i can cange and still be legal .

Also , i am overhauling a LSD carrier for a trans , can you recomend any one local to set my ring gear lash ? ..... Worst case i can do it if i fab up the tools ...... Time vs Money is supose ....

67rschev

As allways i usualy wind up finding the answers to my own posts ....... Look in the manual ding-a-ling ...... found the measuring point for head thickness ...... The surface looked so clean cause it had been worked before . And without being able to run an offset cam key , not really viable to cut more off the head . Damn i hate altitude effect on compresion ......

Randy V

what's to question? The more head the better!

Spidey944

I was waiting for something like that to pop up. Way to go Randy!

Wipeout

V2Rocket

he signed his own citation?

67rschev

Wait till my next post " Questions about the long shaft ....... "

...... A nice topic title allways promotes more views and posts . God i fear this thread is gone Highjacked now

svochuck

"scca e stock solo"

did you see we have the spec-944 as a regional class in RM SCCA ? The rules don't quite match our but they a real close. next year they will be the same as our rules.