Mtrhds94Z

95-7 f body routes the 'coolant crossover pipe' coolant thru the TB then on to the radiator.. [which is also why the 'TB bypass' is easier to do]

93-4 does not...[93-4 routes the 'coolant crossover pipe' coolant directly from back of heads to the radiator]
For 93-4, the radiator inlet hose [ that goes from 'upper driver's side radiator inlet' to the 'upper water pump driver's side outlet' ] has a 'tee' in it, and the 'heater outlet hose connector' [bleeder pipe] has a 'tee' in it also..
these 2 sources then route thru the TB [this is also why a 3/8" hose barb is needed for the 93-4 TB bypass..]
It is possible to do, and I prefer, the 'late' hose configuration,since it gets rid of that funny 'Y' in the 'radiator inlet hose' and also the 'tee' in the bleeder pipe..
Makes a neater TB bypass mod [no 'hose barb', etc]too..

dnz28

just by the sound you dont take your heads off often do you? It gets to be a real pain in the *** when those crossover tubes get stuck in the back of the heads. And it happens everytome to me, those banjo bolt strip so easy the you got to get a giant pipe wrench just to break them things lose. i ve done this 15 times so far in a year in a half.

FireHawk409

On my TB bypass i just capped off both ends. So being that i have a 94 i should have connected the two ends i capped off?? Is that Y piece going to reach to the other side to connect it? I have been runnin my car like this for a few months now i hope i didnt ruin anything.

Mtrhds94Z

I don't think it will ruin anything, but the hoses dangling around might get caught up in something..
Fortunately for 93-4 the steam vent hose still goes to the radiator..
What you can do is get a 95 and later 'radiator inlet hose' [GM 95-7 p/n 10261148 about $21.39 GM list], and a bleeder pipe without the 'tee' [GM
p/n 10262478 $35.07 GM list.. about $17 from Jason Cromer..]
This change to 'late' hose configuration will also allow you to use the Goodyear Hi Miler hose kit, etc, which has the hose without that 'wye'.

FireHawk409

Well i just replaced my radiator hoses. I ordered whatever was needed for my year model. I got both ends capped and the y part i made sure it wouldnt hit anything. So other then that im guessing everything is okay? Ill keep it in mind for the next time i replace them.

Mtrhds94Z

Sure it should be OK then..
Next time you can get a 95-7 radiator hose with no wye..
and at your leisure, you might swap that bleeder pipe for one with no 'tee'.. maybe pick up a used one etc.. that would get rid of one dangling hose/potential leak..

'68LT1camaro

My LT1 had the crossover holes plugged before I got the motor. I didn't realize anything was "missing" until I saw some pictures of the crossover tube. By that time I had allready had the motor in the car, and hadn't had any detonation or cooling problems.

My temperature stays around 172 degrees on the highway, and rarely gets above 180 in traffic. I have built this engine twice, and it shows no signs of detonation.

96capricemgr

Are you monitoring the pcm to see if the computer is just dealing with the detonation before you ever hear it? The pcm can sense it before it is audible and retards timing to eliminate it, if the detonation is bad enough it will enter low octane retard mode and yank timing all the time. This can happen without you ever knowing it unless you hookup a datalogger.

'68LT1camaro

I don't have the factory PCM. I never have. I use Accel Gen 7 DFI.

94 TA TT2S

Anyone have a picture of the routing of the crossover pipr to the Radiator on the 94's?????

shoebox

diagram

NOMAD

If your concerned about removing the heads (which I do frequently), cut the cross over tube and install a hose and clamps to connect the 2 heads. Then you undo one hose clamp and remove only one head if you want. Makes it much easier.

Steam is not the only thing coming through the tube. You can watch the coolant come from the rear of the engine if you have the radiator cap off with the TB bypass done. The long metal line coming from the back of the passenger head leads directly from the head to the radiator. Witht he car at temp and running, you can watch the coolant come out this tube running from the back of the head.

Without the tube, your basically using reverse flow without taking any of the advantages of it.

-Shannon

Injuneer

I actually have a sensor in the return line to monitor the coolant coming from the back of the heads.

http://cjcfo.fbody.com/members/injun...A/DualIATs.jpg

The issue is not "adequate cooling for the entire engine" - in response to the post above citing 180degF and no detonation. The issue is uneven distribution of temperatures in the head, and the tendancy of the #7 and #8 cylinders to run hotter, perhaps made even more severe in the reverse flow cooling layout. #7 is the worst, and I have an EGT on that cylinder, for that reason.

A friend of mine with extensive experience in building nitroused LT1's, set his own engine up with a seperate -12AN braided S/S line from the back of each head, back to the radiator connection. That's how important he feels it is, having seen the proponderance of piston failures on the #7 cylinder.

The minor inconvenience of installing this line, or the extra cost of installing it so that it is easier to hook up is minor compared to the potential for damage from hot pockets in the head. JMHO.