I am trying to do the coolant bypass, can anyone give me a pointer which tubes I need to connect? Thanks

*Push*

I'm not sure you can do that on a tbi or carbed car, the coolant bypass is usually for tpi cars, maybe someone who knows for sure can chime in here.

On my TPI car there was a hose that put hot water through the throttlebody. i just took this hose and connected it to the hose that came out the other side. You don't have the same throttlebody my car has so I am not sure that it can be done on yours.

Here is the link to the article that describes how I did mine:
http://www.thirdgen.org/coolantbypass

Does your throttlebody have a hose that pumps warm water through it?

Yeah man that's for TPI car's only.

Unless your heater core busted and that's what you mean?

If so, take the two hoses going into your firewall on the passenger side, disconnect them and connect them together with a piece of copper tubing or something and some hose clamps. Done. No heater, but engine cooling still intact.

all that $%#% connects to the smog pump. u can remove it and run a shorter belt

This is hilarious. If you don't have enough comprehension of the modification to know that it doesn't apply to TBI cars, you probably shouldn't be modifying your car. Keep reading before you make changes that could cause damage.

Yeah, dump the smog pump and spend $15 on a shorter belt, that'll free up just about nothing and make your engine compartment look like a hillbilly hackjob... Now that's what I call a worthwhile mod!

Just another tip when it comes to the problem being a busted heater core. Interestingly enough, on my TBI car when the heater core went bad, I didn't even end up having to bypass the hoses going to the core. All I did was move the selector on the heater controls all the way over to cold and it quit running through the core. Apparently on an A/C equipped f-body, if your bypass valve works correctly, without any internal leakage, it'll completely block off the flow to the heater core. I just left mine on cold all summer. When winter starting creeping up, I finally got up the gumption to change the core out so I wouldn't freeze to death driving around!

I find it disturbing the amount of bad and WRONG information in this thread

TBIs are easier to bypass than TPIs

Cap this


Run a short piece of line from the core line closest to the HVAC box to the back of the intake. I reused part of the old line that went there


Be sure to plug the old vacuum port from the valve or your vents wont function

The process is the same for TPI, except the intake port is in the front, so there will always be a heater line running over the engine

Thanks Pocket,

I am going to try this tomorrow, plus I wanna take the heater out of the circulation completely by connecting these two cables directly.

By the way, what thermostat and fan sensor rating would you suggest for this car?

That's all you need to do; connect the 2 hoses (not cables) together.
You don't need to do anything to the valve vacuum line unless you're removing the hoses and the valve in which case plug the source of each hose at the intake manifold and radiator, or wherever they come from. I'd cap the heater core lines as insects will get in and plug it up if you leave them open for a long time. If it's no good then it doesn't really matter if you don't cap them.

As far as T-Stat and fan sensor, the car looks stock, why do you need to change them?

Connecting the heater core lines will only keep the small amount of fluid already in there still. Id leave them open

To remove the HC from the system, cap the line at the rear of the intake and the small coolant line on the pass side of the radiator. Both use 3/4 caps available at any parts store

Thanks for the info Pocket.

The heater has stopped working and I dont really need it in south cali so I just want to keep it out of circulation.

The reason for changing stat is that the car seems to overheat a little bit. It goes to around 230 before the fans start working and then goes back to 220 and this pattern continues throughout driving. I did some research here and it appears that this is the temp it was designed to operate at but I see many have suggested to replace the Tstat and the fan sensor to get a cooler temp.

i put a 160 in mine during the summer and it runs about 180* in 100*+ heat here in az, as for the fans youd need a radiator sensor setup or use a tuning program to change the fan kick on temps

good luck!

Actually on a TBI car the computer has nothing to do with when the fan kicks on. The only thing that controls it is the switch that's screwed into the passenger side cylinder head. If you want it to run a bit cooler, I'd suggest putting in a 180 t-stat and using the stock fan switch for an 87 Buick Grand National. Hypertech sells lower temp fan switches, but they're ridiculously expensive. You can get the GN switch at Autozone for about $21.00 (Everco Part#35946). This switch kicks the fans on around 207 degrees instead of the factory setting of almost 230. The Hypertech switches will kick the fan on at even lower temps, but they cost about 50 bucks. On my TBI car I used to swap back and forth between a 195 stat for heat in the winter and a 180 to run cooler in the summer, but since you aren't going to use a heater, you could run the 180 year round, or even go with a 160.

and then do what i did if you want, add a manual on switch when you want it on