TV boost valve

["More Boost"]

does anyone know the stock size tv boost valve for my gn (brf) trans. i was wanting to purchase a .500 boost valve with teflon seal ring but if my gn already has one be kinda useless. please, thanks, Gregg

 

[Lee Thompson]

here you go !!!

.471

 

["More Boost"]

thanks lee, would this be worth installing or would it be a waste of time and money? .029 doesnt sound like much diff. , but im not a trans. guy.

 

[blackplague]

The Stock TV boost valve

measures .422 . The .471 was reserved for the 700-R4 for the vette.

 

[Firechicken]

To crank up a bit more pressure, PTS makes a .570 valve. Get it from them or they also ditribute them through TCI. They also make a .400 low/rev boost valve which is much larger than stock too and is desirable.

For reference the TCI part numbers are:
374410 - .400 low/rev boost valve
374401 - .570 boost valve

 

[Lee Thompson]

sticker shock!!!

Be prepared for sticker shock if ordering from TCI. Call this # for a good price on larger boost valves-812-280-1143--I still believe .471 is the stock size. I have some .471s laying around and I have never touched a 700.

 

[Firechicken]

Ya they are pricey. I'm not sure what PTS sells them for, nor what TCI sells them for, but Summit has the .570 valve for $31.95 and the .400 for $49.95.

 

[GNeric]

Lee is correct. The largest TV valve GM made for the 200-4R was the .471 in the BRF. Corvette had them also as did Z-28.

 

[chris718]

the .500 is cheap and works.anything larger opens the door to pump rotor and slide breakage due to the excessive amount of pressure built up in the pump body before the valve opens.the .5 will give 210 to 240 psi max line,all you need.all of the aftermarkets pieces ive seen were poorly machined and ive seen three of them stuck.not worth the effort imo.

 

["More Boost"]

i bought a billet super servo (fairbanks) i think, would this compliment the .500 boost valve? any input would be great, thanks, Gregg

 

[bison]

i bought a billet super servo (fairbanks) i think, would this compliment the .500 boost valve? any input would be great, thanks, Gregg

It'll work but be sure to run the cushion spring or you may break the bad anchor pin off. The biggest problems in this trans lie in the stock direct oil feed and the 2-3 shift timing. You need to evaluate your performance goals and then choose your parts.

 

["More Boost"]

so, if i install a shift kit will this improve the stock direct oil feed and 2-3 timing? i was told a larger boost valve comes with a new shift kit but mine didnt. this is a street driven car. the trans (BRF) shifts real firm now. i just wanted a little more durability out of my trans. (longevity) :biggrin: