blodi

OK, F2 150/240 and the accell circuit "blocked"....so....uh....that didn't do what we thought at all.... 52218 by blodi, on Flickr

I plugged the accel circuit and put in 150 mains last night. I'll report back when I have a chance to drive it.

F2-140/240.... 51618 by blodi, on Flickr Looking back through the logs to refresh my memory i'm thinking we were closest with the F16 155/185..... I still need to block the accell circuit and see how it impacts the richness up front.

Drove the car into work today. Took a log over lunch so I'll load that up tonight. Running the F2 140/240 setup. Car is running great though!

That's impressive! Gosh, I have to go back just to remember where we even left off with my settings. I took the car for a quick spin last night and she is running really nice. Hopefully I'll get a few miles...maybe an updated log this weekend.

Ok...where were we? Oh yeah...tuning webers....lets get this thread back to that! IMG_5211 by blodi, on Flickr

Head is done. New seat and valve installed. Everything else checked out fine. Gotta get it back and install everything once again. Then hopefully we are just back to tuning!

Head has been dismantled, inspected and a new valve and seat have been ordered. My mechanic thinks that the seat may have gotten installed slightly off and was eventually just knocked loose by the valve. Should have it back within a couple weeks and install.

I think the seat hit the piston...thus the wider diameter that hit. Missed it by that much. Piston damage is actually very minimal. Yeah, the motor was built with all the right stuff......but the dude was asleep at the wheel when he installed that particular seat. I'll hand it off in the next week or so and then we'll go from there. Honestly...I'm just glad to have found the problem and will rest assured that it will all be good from here. Heck, we might even get this thread back to being about tuning carbs sometime.

Head is off. On the plus side I found that I do have the larger valves in this E31 Head. Also the bore measures 87.5. So it’s bored out a bit.

Got the carbs, intake, header and thermostat all removed yesterday. You can clearly see the valve seat dropped down in #4 intake.... Once my chain wedge shows up I’ll get the head off.

Mike, sounds exactly like what happened here. I have to believe my seats have all been upgraded since every other part of this engine has been upgraded. It was hard to tell on my grainy bore scope.

Agreed. I am going to start pulling the carbs/intake/header on Monday since I have the day off. I ordered a timing chain wedge yesterday. When the head is off I’ll let my friend/mechinc have at it I think at minimum a new valve seat will need to be installed and the valve replaced. I’ll have him inspect all of the valves and seats though.

The seat looks to have come loose and wedged itself between the valve and head. It didn’t drop to the piston but rather held the valve down enough to tap the piston. This has all been on the same #4 intake valve. So I think the seat had been coming loose and causing the valve to close slowly and this getting the tapping and eventual loss of the lash pad each time. This time since the lash pad wouldn’t come out being lower into the retainer...the seat came completely out.

Ok, well.....got home from work and fired it up again. Sure enough the tapping came back after about a minute of running. Then after another minute or so and a few quick revs the tapping got really bad...so I shut it off. Pulled the valve cover and saw that now hte #4 valve was not up to it's full up position even though the lobe was not pushing down on it Got my bore scope out and looked in the spark plug hole and could see a fresh mark on the piston from the intake valve. Then went though the intake and can see that the valve seat came completely loose. Fack. So....that's my Thursday night. Going to think about how to proceed. Might wait and have my friend who is wrapping up an engine rebuild on my NSX have at it once he is done with that car in a couple weeks. He'll be able to comb over everything much better than I could and he's basically an NASA engineer when it comes to assembling and inspecting engines. Not the outcome I was hoping for but it is what it is. Not sure why the seat came loose in the first place, but it all makes a lot of sense now.

Yes, I did reinstall the washers before putting in the new seal. My understanding is that ultimately the wipe pattern is setup by the lash pad as it still sits directly on top of the valve itself since it's flat on the bottom. So the retainers shouldn't have any impact on that geometry. The picture of the pads sitting in the retainers before installation isn't really representative of how they sit once installed on the valve.

Ok, got my valve spring removal tool yesterday finally. So I removed the retainer/spring from the valve in question (#4 intake). IMG_4715 by blodi, on Flickr There was a washer under the spring and one under the valve seal as well....normal? IMG_4716 by blodi, on Flickr Washers and new valve seal installed.... IMG_4717 by blodi, on Flickr New Schneider valve spring and retainer on left....old on right... IMG_4718 by blodi, on Flickr .170 lash pads installed in each... IMG_4719 by blodi, on Flickr Installed...... IMG_4721 by blodi, on Flickr Rocker arm back in place and lash adjusted.... IMG_4723 by blodi, on Flickr You can see that the lash pad certainly fits much further down into the Schneider retainer than the old one. I started the car for about 30 seconds and then my 1 year old woke up and I had to call it a night. Didn't hear any tapping though....but hopefully tonight I'll have a chance to start it up and let it warm up and see what is what. If all is well...I'll have to maybe spend my day off on Monday replacing all the rest of the springs retainers. Oh, also...I was able to spin the valve around freely and didn't feel any binding. It had just a tiny amount of play in the valve guide...not sure what is "normal" there but it didn't feel excessive.

Yes. That first tool is similar to what I had and realized it won’t work because it doesn’t grab the inside spring too. So I ordered that tool at the bottom which I’ve read works. I’ll post updates. I got the cylinder stuffed with rope already.

Schneider confirmed that the 68022 springs are correct for my application. I also had to order a differnt spring removal tool as the one I had wasn’t working.

I wish I had a build sheet. I don't even know the bore of the engine. I don't see that the towers have been shimmed. Looks like the bolt right down onto the head. I just sent an email to Schneider to confirm what springs to use. I did order the above parts today, but they won't ship til Monday.

Yeah, I have a American Custom Cam 500/300 cam. So upgrading certainly won't hurt. Looks like the prices haven't really changed.

Thanks! I'll order up a set. Can't hurt. I got a tool to remove the retainer. So I'll do that and just try maybe putting the Schneider spring/retainer on that valve just to try it. Also I'll look for any signs of the guide/valve being messed up.

Where can I get the springs/retainers? I am not sure what part number I need from Schnieder's site.

Ok...here are a couple dumb questions: -Do I have to remove the head to replace the retainers/springs? Seems the valves would just drop if not right? -Would the same lash pad thicknesses apply to aftermarket retainers? I guess so since the pad still sits on top of the valve directly. The springs I have in the car are a dual spring setup....is the stock setup dual? Yeah, it seems like for as massive of a cam as this is....it should have some good springs/retainers to keep up. Still...I wonder why this issue would come up only after 3K+ miles on this engine....and only on the #4 intake valve.....maybe those particular springs are just getting weak?

Backup and never ran. Still were crosshatch marks on cylinder walls when I got it that saw with my scope.