Folks, I need to know what size pilot shaft to buy/order to cut the valves and seats on my B18A1 Head. I dont have the valves to mic, so therefore, I am having to ask if anyone can tell me the size of the valve shaft, so I can order it.

Thanks,
Scoo-D

 

dont let them do any work to the head without the valves, each valve will be machined for one individual seat and installed height! intake valve stem diameter - 6.58-6.59mm
exhaust 6.55 - 6.56mm these are new valve service limits, youneed to check your guides in order to know what to buy and also the guide to vlave tolerance.

 

5.5mm

 

I have the valves, head, AND a SIOUX machine at our disposal. Each valve? That is SIXTEEN damn valves. My father was planning to do the work. Oh my Lord. I can't believe that we can't just cut sixteen seats, and sixteen valves and make reassemble.... Why is this? I need an explanation to pass along to him. He is from the old school machinists.

Thanks for the help also!
Scoo-D

 

well then atleast go 60degrees then 30degrees andvery light 45 degree cut on the seats, you will want to check installed height which is often overlooked and if you cut too much off the seats you cant add it to the valves. if your dad uses blueing (prussian blue) to see where gaps and seating is he will want one specific seat cut for one specific valve. p.s. my valve stem diameters are for 98+ doubt they changed from earlier models though.

 

It does not matter what year your B series head is they never cam with a valve that is 6.5mm you might be referring to the OD of the guide but the ID and the size of the valve stem is 5.45 on the exhaust and 5.47 on the intake.

a valve job is not specific to ONE particular valve to the next, you check valve height and cut the seat, lap them in when your done. So believe yourself you can just cut sixteen valves and sixteen seats and lap them in and assemble. You definitely don't want to sink the seat but if your dad has done valve jobs before the concept of it hasn't changed since it was introduced-meaning your head doesn't know it's a Honda so you should be in good hands.

 

uh I just got the info out of my service manual from Acura - double checked those figures and they still refer to the diameter. I'll just stay out of this one for now.

just checked ferreas site - LS/GS motors - 1990 - 2000 my specs are correct / all others are 5.45

http://www.ferrea.com/cgi-bin/...es.pl

 

holy ****! I feel like the biggest ***! I read B18 and automatically thought the C head I am soooo sorry guys, Rtype I apologize to you to. I guess I should have read the whole post!
Rtype is right about the stem diameter- sorry again.

 

dont apologize to me I am the biggest ******* around.

 

Thanks you all.

This info will be great to pass along. I esp. like the part about the angles. so I am supposed to get a pilot tool that will fit the 6.55-6.59 mm right? I understand that the Sioux machinists used a common guide that ranged in sizes. Any thoughts?

Thanks again,
Scoo-D

 

I will let someone else fill in for info on the Sue machine, I can hand lap with iskendarian valve tools, I am more familiar with sunnen. when the machinist sees the actual valves he will most likely determine depth of cut.

 

Ok so you have an ls head correct??The correct pilot size is hard to say ,you have to account for the original guides wear from new.It could range from .257-.260 on a very worn guide.But let me ask this one question ,why are you cutting the seats before you get valves?W/O the valves to measure how will you set up the cutter to the correct size?

 

OK, here is the deal.

I HAVE THE HEAD. I HAVE THE VALVES. THEY ARE AT MY POP'S HOUSE, 65 MILES FROM ME. HE IS DOING THE MACHINE WORK. WE HAVE NO PILOT TOOL.

I have to buy a pilot tool to fit my valve guides, so that we can cut the valves and seats. I cant exactly BE there to measure the valve guides, and he is kinda in and out frequently. I just wanted to get an idea of which tool I need to ask for. I have recieved a lot of great help thus far, and thank you.
Tech seems like the place to ask for help. Any one familiar with Sioux machinery?

Keep it coming guys! Good work!
Scoo-D

 

Like I said before you can't just measure the valve shaft and order a pilot.You have to account for wear of the guide.Pilot's are sized by the thousandth of an inch so w/o knowing the wear your'e going to have to buy like 3 pilots and use the tightest one,just return the rest that weren't used.I have about 6-7 pilots for just b series heads alone,every head has a different amount of wear.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRneXt &raquo;</TD></TR><TR><TD CLASS="quote"> I dont have the valves to mic, so therefore, I am having to ask if anyone can tell me the size of the valve shaft, so I can order it.</TD></TR></TABLE>

That was you who said that right??Please don't yell at someone who's trying to help or you won't get any help!!