i just finished my mpfi 3.1 v6 to my tpi 5.7 v8 swap ( open header rocks ), but right now i have a little problem i hooked up all the lines the same way that they were at the junk yard. now here is the problem when i start up the car coolant leaks from a hose on the throttle body and sprays all over the motor/headers. i have looked at this diagram ( W/C41 ) and found out that it needs to go to the hose coming out of the firewall. originally when i had my V6 those were never used, and the nipple where the lines go to after it goes to the core has always been sealed with a little piece or rubber. is there a way i can bypass this or should i just run the hoses the way they are supposed to be ran. also there is supposed to be a nipple above that one on the radiator for the coolant tank right? lastly how do i know that there is going to be a heater core i would hate to run coolant there and next thing i know my car is wet lol.

 

you can bypass if you have the inlet in the radiator then you can run a tube from the TPI to it. sound like your can was already running a bypass in the old setup so even if the core is there it more than likley has some issues.

 

See the hose that come up from the center/top/front of motor? That goes to thottlebody to heat it up in the winter. Then it comes out to the side of tb to pipe #6 to hose #2 into heater core than back to radiator from hose #7. First you can disonnect hose #2 and #7 and plug #7 end and blow hard in #2. should hold preasure and if you lift #7, should feel you breath. Know what I mean. very crude, but will tell you if blocked or heater core open...Etc. You can run a hose from top of motor to the radiator and by-pass TB and heater core if you want. I disonect TB for summer anyway. Hope this helps you out. BTW, is the leak from a lose hose clamp or is the TB itself leaking? You need flow from motor to radiator or may get too hot. If you do the complete by-pass....No problems...

 

it wasn't really a leak it was pouring out because that hose wasn't hooked up to anything. i ran a hose from #7 to the manifold that way its all bypassed and i live in florida and its always like 110 lol