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hey guys i have a 2012 4l60e valve body that i am repairing with oring end plugs, blocked 3-2, sonnax abuse plugs/valves, fitzall tcc valve with seals. i went to vacuum test it and everything is holding perfect vacuum except the tcc valve the stock part of the valve that fitzall valve makes you put in. pulls around a 8 of vacuum. i had a sonnax tcc valve laying around and i used the end of that valve that part doesn’t need ream it went right in then i retested it and pulls about a 12 still too low for my liking. my question is this since the fitzall makes you put the stock valve in does it matter what the vacuum reads on that spot? hate to get a new valve body when this one is testing great.
hey guys i have a 2012 4l60e valve body that i am repairing with oring end plugs, blocked 3-2, sonnax abuse plugs/valves, fitzall tcc valve with seals. i went to vacuum test it and everything is holding perfect vacuum except the tcc valve the stock part of the valve that fitzall valve makes you put in. pulls around a 8 of vacuum. i had a sonnax tcc valve laying around and i used the end of that valve that part doesn’t need ream it went right in then i retested it and pulls about a 12 still too low for my liking. my question is this since the fitzall makes you put the stock valve in does it matter what the vacuum reads on that spot? hate to get a new valve body when this one is testing great.
unless I am mistaken the fitzall HAS NO MOVING PARTS internally or externally its simply changes lockup to ON/OFF not something I generally suggest in HIGH peformance cars and trucks because it allows line presure to apply the Converter clutch, Now in a stock tune this is not such and issue as lockup is disallowed at WOT HIGH LINE condition and can only happen at light part throttle crusing so the CLUTCH WOULD NEVER SEE MAX LINE, But many performance tunes use lockup at WOT for several things including DYNO runs or in my own cast with a triple disk mine locks at WOT above 3800 RPM as I gain 40ftlbs torque that way to the wheels.
But with the fitzall that means full line to the converter clutch which can damage the converter clutch, converter face distortion and apply excessive presure to engine thrust bearing. With the FITZ all however to answer your question the isolator valve does nothing and you can even block the feed to it. Though it will cause no issues either way if it is a concern for you. If you do plan WOT lockup I would suggest instead the SONNAX valve for constant presure or the sonnax/transgo or any of several individual methods that retain the PWM controlled slip lockup instead.
In my case I sue a small spring behind the ISOLATOR VALVE and an orings end cap on the valve which has never failed me on acheving good lockup with no codes or issues. But that is my method. Transgo used to make a drop in replacement but they seem to have dropped it . The other option is the SONNAX valve which is expensive with the reeming to for the single user.
Now if you never plan to use WOT lockup then the FITZALL should be fine as the converter clutch will never see max line applied.
__________________ Frank formerly of Performabuilt, Now just me, What can I build for you today? Call or message me. Click sig pic for my facebook
unless I am mistaken the fitzall HAS NO MOVING PARTS internally or externally its simply changes lockup to ON/OFF not something I generally suggest in HIGH peformance cars and trucks because it allows line presure to apply the Converter clutch, Now in a stock tune this is not such and issue as lockup is disallowed at WOT HIGH LINE condition and can only happen at light part throttle crusing so the CLUTCH WOULD NEVER SEE MAX LINE, But many performance tunes use lockup at WOT for several things including DYNO runs or in my own cast with a triple disk mine locks at WOT above 3800 RPM as I gain 40ftlbs torque that way to the wheels.
But with the fitzall that means full line to the converter clutch which can damage the converter clutch, converter face distortion and apply excessive presure to engine thrust bearing. With the FITZ all however to answer your question the isolator valve does nothing and you can even block the feed to it. Though it will cause no issues either way if it is a concern for you. If you do plan WOT lockup I would suggest instead the SONNAX valve for constant presure or the sonnax/transgo or any of several individual methods that retain the PWM controlled slip lockup instead.
In my case I sue a small spring behind the ISOLATOR VALVE and an orings end cap on the valve which has never failed me on acheving good lockup with no codes or issues. But that is my method. Transgo used to make a drop in replacement but they seem to have dropped it . The other option is the SONNAX valve which is expensive with the reeming to for the single user.
Now if you never plan to use WOT lockup then the FITZALL should be fine as the converter clutch will never see max line applied.
this valve body is going to a truck that is just cammed on e85 4.8 so nothing with crazy power and it’s tuned to never see lockup on wot. i was just worried due to the sonnax vacuum diagram that states to vacuum test that port and could cause 3-4 burn up. yes this fitz valve just blocked it inboard that’s why i thought maybe i can still run it since its just blocked inboard. i just wanted to make sure that it’ll be fine i don’t want the client coming back in a few months saying he has no 3rd haha don’t want him to have the same issues he had with his monster unit that was junk. thanks for the advice of the tcc valves and for higher hp i plan on buying the sonnax reamer tools since i’ve been doing this more and more slowing learning more and more as i go.
this valve body is going to a truck that is just cammed on e85 4.8 so nothing with crazy power and it’s tuned to never see lockup on wot. i was just worried due to the sonnax vacuum diagram that states to vacuum test that port and could cause 3-4 burn up. yes this fitz valve just blocked it inboard that’s why i thought maybe i can still run it since its just blocked inboard. i just wanted to make sure that it’ll be fine i don’t want the client coming back in a few months saying he has no 3rd haha don’t want him to have the same issues he had with his monster unit that was junk. thanks for the advice of the tcc valves and for higher hp i plan on buying the sonnax reamer tools since i’ve been doing this more and more slowing learning more and more as i go.
Only leak you will have with the FITZALL is a small AFL leak to the isolator valve. Should be no issue but if woried just ping it shut
__________________ Frank formerly of Performabuilt, Now just me, What can I build for you today? Call or message me. Click sig pic for my facebook
OEM VB has very sharp edges and first set of fitzall seals was demolished just in 5 min nevertheless I used plenty of grease
After that I bought set of coned burrs for dremel tool and make edges rounded from both sides of every wall in VB that can(and will !) cut my last set of o-rings
Only after that I achieved zero leaking
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4l60e TCC 
