madkaw

2006 STI diff 3:90 gears - clutch type custom made aluminum DS FUTOFAB CV axles new front diff mount RT upper GM style mount It seems to be excessive drivetrain slop causing a clunk based on how the clutch is released. The excess can be seen and felt by hand when rotating DS by hand while in gear. It seems the slop causes the driveline to clunk when engaging torque . Easily duplicated when cruising at low speeds and engaging clutch in a higher gear (4th). I have had someone duplicate this in the garage with front wheels chocked as they let out clutch rapidly in 2 gear and I have watched for any movement - I see none. Harmless slop or diff worn out ? The only other noise I get from the diff is a bit of a chatter when pulling into my garage ( uphill ) at slow speed. I can hammer the gears in WOT and hear nothing .

I think your a little confused on what’s being done here. The valve likes to have room to breathe all the way around the valve. Obviously close to the cylinder wall side is where there’s not much room. So no it’s not ballsy to clearance close to the fire ring if done right. Your exhaust valve side needs work in the green arrow area of your first pic. I’d follow the radius of the valve all the way to the fire ring ( or very close). Make sure you have your head dowels in place holding the HG where it will sit when installed. Do not take any material away from other areas UNLESS you need to adjust your CR by gaining CC’s. That’s probably what Brapp was doing with a small chamber head. Smoothing edges is great but you don’t usually remove much material.

There’s material that could be removed ! Not sure what you were expecting to find but that exhaust could use some work for sure

Okay - I can’t let you slide on this one. you think you had to point out what was exhaust side and what was intake -lol

Did you try moving / adjusting dizzy to different positions while starting ? Maybe timing is pretty far off . Lining up the oil pump has to been done accurately . That 11:25 o’clock position can be tricky to eyeball and it wouldn’t take much to be a tooth off. Double and triple check firing order. Whats it doing when you try and start ? Spitting , coughing , nothing ? Try squirting starter fluid in while cranking ?

Did you align the cam TDC COMPRESSION STROKE!

I’d help you out but your still 4 hours away , plus I think I forgot how to work on carbs now :0 now if you go Megasquirt I’ll set you up !! Youll need to sell off the Weber’s to pay for EFI , but won’t regret it

You will have to pull the dash

I’ll repeat what I said on FB - that panel is worth saving

No current dyno runs. With SU’s I did 155 with my L24 . I plan on taking my current set up to the dyno- but other than EFI , no changes , so I think similar results .

My 490 ISKY pulls hard to 7000, but I can’t be specific about the cam timing . My head is shaved over 50 thou without using shims and have my cam advanced 8 degrees. I didn’t degree after the last 20 thou shave , but with 30 thou cut the cam almost cam in too late . The other factor was I went from triples to n42 injection ( Megasquirt) . If that graph was accurate then it would seem that it wouldn’t be as user friendly on the street at low rpms. My ISKY just puts along at 1500 rom in fourth around town without a jug

My understanding from Steve Bonk- who sells these - if I understood him , was that the shorter duration helped with clearance issues even with its high lift . But don’t quote on me on this

Duration 315?

I thought the DP cam had a shorter duration which in turn would not be making power later than the Isky- but I’m guessing here. So the higher lift is killing the low end?

35$ hall sensor , DIY flywheel drilling- out of sight

Then the valve was defective if I understand the way it works correctly. And I believe the vent line goes to the valve - not the crank breather tube. Valid point about vent line being higher than tank for sure .

Actually - the way that valve works there is no direct air route from the PCV to the tank. What opens the vent valve is pressure build up from the tank. You can test the valve by trying to suck air thru it.

On my 71 , I ran the vent fitting on my Tank Inc in flex line all the way up front to the original vent valve on the fender .

Should of went high impedance injectors IMHO- would have mounted in with a Pallnet fuel rail easy. I know someone who has the dizzy if you need it. You are going like the MS once you get it going. Some good help available here

Damper Doc did mine years ago and guaranteed like 8 grand rpm and 400lbs torque . I’ve had no issues and it was about the same price.

Page 2 has some good discussion.

Might need to elaborate on this statement

How much for their rebuild?

Hell- if you willing to spend that money , buy one of Datsun Works heads and something truly special