Hey,

I began running a throttle body coolant bypass on my 87 firebird 5.0 tpi. what i did was run the hosing from where it exits the intake manifold straight to the heater diverter valve instead of intake manifold to tb to diverter valve as it is stock.

Now I have blown up my heater diverter yesterday and in feburary of this year. Has anyone had similar problems or did i just get a shitty valve from napa that couldnt hold up? from a thermodynamics standpoint i wouldnt think that the pressure would be different whether it runs thru the TB or thru the bypass

thanks

 

I would say it's the part, I did mine a while ago and haven't had any problems, as of yet anyways.

 

i would say part failure. but what is the benefit to doing thise? all i see it doing is giving u shitty fuel mileage.

 

well the idea behind this is simple. from a thermodynamic standpoint, the larger the temperature differential, the greater the efficiency and power. this is the same reason why a cold air intake does more than a same intake breathing hot air.

this is modeled by the equation: ideal efficiency = 1/(1 - tl/th)

 

hah shuda figuerd tht out myself. is it a noticable difference in power tho? and how does it idle in the cold mornings?

 

Those heater diverters are crap. I broke one when I was taking my TB off to change the IAC. Go to a yard, and pick up a few. They're pretty cheap. But order a new one from Rock Auto if you want.

The problem is I don't think they were meant to just hang in such a hot place on your car. If they were bracketed, they'd probably do better, or if they were a different material, they'd probably do better.

 

I know I got a little different engine but on my LT1 I did TB coolant bypass. I also got rid of the heater valve altogether and ran heater hoses directly and put a vacuum cap on the vac line that was going to the valve. Its how they ran hoses on the old cars. Less complicated, cleaner engine bay, less parts that can fail/break.

 

yea, i think i might just gut all that heater stuff next time that hose on the firewall that runs from the heater core to that steel pipe goes. i did that once and its damn near imposible to get back on with the TPI engine and now that i got the headers on id have to pull the engine to get it off and on, haha. who needs a heater, just put on a coat.

 

its been proven to make less than a 1 horsepower difference

 

i didnt say it was going to make a noticeable differance, but hey its free horsepower, why not take advantage of it

 

I did the TB bypass on my 86 and you can feel a definite increase in performance. The aluminum intake runs cooler and it takes longer for it get hot and start degrading performance.

Runs great in cold weather, but then again Texas weather doesnt get as cold as it does up north.

The problem I had is with the routing of the heater hose, always has a bend in it to go around the big alternator bracket. I had one of those rubber plugs I capped the aluminum intake off with burst a couple times.

 

yeah thats issue, i dont drive it in winter but spring and fall we unexpectingly sometimes get below zero...32* for u. i dont really want the throttle body icing up.

 

honestly i dont kno what ther is to ice up on the tb. ur not running coolant thru it and there shud be no moisture near it....

I mean i drove mine around this winter a bit when it was like -40 (windchill anyways) and never had a problem

 

it can happen even in not too cold temperatures (supposedly) just from the fairly warm air under the hood, and the sometimes fairly cold air going through the throttle body, especially if you have a CAI. ive never bypassed it, or experienced an iced throttle body, just passing along the knowledge ive learned.

 

I hav`nt seen/felt any power gains with the bypass, just 1 less thing to leak. Try another brand of diverter valve, my Kragen cheapie works without problems.

 

I deleted mine entirely just to get rid of the hoses.