I've came up with a solution for the casting flaw
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Changing Intake ports to a D shape for better flow.
- Thread starter Jack
- Start date
So am I!
Here is the method I'm using for anchoring the JB Weld and what I try to aim for is centering the 1/4 x 20 studs with the guide axis but due to casting
it's not possible all the time. All the studs are coated with Loctite 272 and torqued to 125"lbs. The arrows are the areas I had issues with casting,the
top area is pointing to the section beneath the floor of the spigot between the bottom head fin to the one just above it and the other arrow to the right
didn't have enough casting in the width to center the middle stud on the left port. My fix as you can see is loctite a stud in place, cut the stud flush, then
build up that area by welding to re-drill and center the middle anchorage stud.
it's not possible all the time. All the studs are coated with Loctite 272 and torqued to 125"lbs. The arrows are the areas I had issues with casting,the
top area is pointing to the section beneath the floor of the spigot between the bottom head fin to the one just above it and the other arrow to the right
didn't have enough casting in the width to center the middle stud on the left port. My fix as you can see is loctite a stud in place, cut the stud flush, then
build up that area by welding to re-drill and center the middle anchorage stud.
You can clearly see in this image how much off centered the middle stud is. You have to install the first stud close to the short turn, coat it with loctite
and screw it up from the bottom and seat the stud threads by a nut and washer and snug it real tight. After the loctite has cured, I'll remove the nut
and gauge the stud to the desired floor height. The reasoning for these studs is not only for epoxy anchorage but to use has a guide for floor height
when cutting the excess epoxy with a large file,then work the floor corners with the abrasives.
and screw it up from the bottom and seat the stud threads by a nut and washer and snug it real tight. After the loctite has cured, I'll remove the nut
and gauge the stud to the desired floor height. The reasoning for these studs is not only for epoxy anchorage but to use has a guide for floor height
when cutting the excess epoxy with a large file,then work the floor corners with the abrasives.
The right port anchor studs are close enough.
Simply brilliant Jack!!!
spungle
XS650 Enthusiast
Danke gleichfalls!
Oh My! 34mm RS flat slides, gonna be a rock solid combination blitzing the streets raising hell with the Polizei on your tail
Oh My! 34mm RS flat slides, gonna be a rock solid combination blitzing the streets raising hell with the Polizei on your tail
spungle
XS650 Enthusiast
Don't mess with the cops
Jack, have you ever considered using D shaped aluminum tubing to make your ports?
Yes I have and there far better pros to using JB Weld, much more forgiven in reshaping especially when working the short turn, provides an insulated
barrier in the floor and unlike most low percentage silicon aluminum, JB and cast aluminum thermal expansion rate is the same making it ideal for
modifying aluminum ports. Once the engine goes through numerous heating and cooling cycles JB becomes harder and adhesion is intensified from
my experience.
Thanks for the kind words but this type of anchorage is common practice and for the XS I think this is the best approach addressing vibration frequencies.
Well I was able to shift the middle stud over slightly but it was a challenge cuz I had to start the pilot hole on the very edge of the stud and the bit was flexing and shifting to the side. Whipped out my sharpest high dollar Snap On 13/64th bit, these are very impressive bits too and it was like cutting through butter
Looking a lot better. Will cut front stud to depth and continue backwards till the studs are gauged to spec
Jack, are you considering D shaped exhaust ports as well? I've read that Chevrolet is using D exhaust ports on Corvette engines now.
No I'm not, it's a real PITA trying to weld up the E/P ,most always the end result is burning through the short turn. Once the ports are cleaned up ,they flow
exceptionally well despite the turns in the port.
Sorry I haven't been posting updates on Chris's head but I've been dealing with severe Sciatic never pain and it's difficult for me standing for long periods,even short periods,so I needed a few days of recovery to relieve the pain.
I've finished installing all the anchor studs,just need the Loctite to cure for the last stud. Tomorrow I'll finish the last stud height and start preparing to apply the JB Weld
I've finished installing all the anchor studs,just need the Loctite to cure for the last stud. Tomorrow I'll finish the last stud height and start preparing to apply the JB Weld
To prevent JB sticking to the valve seat angles,I've made this plug from Minwax wood puddy to control overflow and to shape the epoxy short turn minimizing sanding.
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Another image of the plug and will apply a light coat of grease preventing JB sticking to the plug
