Ok, I know everyones seen the simple bypass mod. I wanted a cleaner look and since we were converting my 83 Z28 to a TPI 350 heres what I did.

I purchased a billet IAC housing from TPIS, a 90* heater hose fitting from performance stainless (intake) and a 45* heater hose fitting (water pump) from A-Line auto parts. I just finally got around to taking pics...As you can see the fittings must be installed during during assembly as the fuel lines will be in the way.

 

A cutoff wheel could have saved you a good chunk on the billet piece that'll never be seen

 

looks pretty good, but you wouldn't happen to have pics of the underside of the TB? I did similar with the coolant lines, but I ran mine behind the water pump and away from the top of the engine...

 

I did the cutoff wheel thing three years ago. When I came across the billet piece I just wanted it. I also have a billet fuel pump blockoff plate.

 

Where could you get that block off plate at?

Thanks. Tony.

 

Jegs

http://www.jegs.com/i/CSR/170/660C/10002/-1

It comes with stainless bolts and gasket...

 

But how can that work when its made for a fuel pump?

Tony.

 

Huh? My car is an 83 Z28, I converted it to TPI. Had to ditch the block mounted fuel pump.

 

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even if your car is fuel injected the block still has a spot for a mechanical block off plate this is just to make **** pretty

 

Can you see down there?

 

yes its on the passenger side of the block right in the front just next to the header, down a few inches just below the heads

 

What are you doing to block off the radiator line?

 

Who is blocking off a radiator line?

 

no ones blocking anything there just putting a fitting in between the two hoses that flow coolant through the throttle body. not changing anything at all with the flow.

 

so your still running the line from the radiator to the heater core.

was just looking at the photos. and i was thinking you ran from the top of the water pump. to the heater core.. than into the intake.thats all.

 

Yes, the 90* fitting in the intake is to the heater core and the 45* fitting on the water pump is from the heater core...or the other way around. Can't remember which way the coolant flows.

 

my 92 runs from the radiator. to the heater core..Then
from heater core to TB.

I see now your useing a diff styl water pump.and dont have My style of Radiator.

but it's the same out come taking the TB out of the loop from Hot coolent.

the way my 92 would work would be.. from intake to heater core..from heater core to Radiator.. thanks

 

.

 

most of the guys wantn the most out of the eng at all times will do this..
and one i have been wantn to do..and will with the nexed Eng..

it's the lines coming off the heater core that are a PITA.
my tranny dipstick is right there....looking at having 90deg AN fittings fitted to the Heater core. (i hate the way) they get in the way.

 

no no... tony wanted to know where you get the throttle body block off plate, not the fuel pump block off.

 

If you're not using a heater core, can you bypass the throttle body by connecting a line from the water pump directly to the fitting in the front of the intake manifold? Also, as it was asked previously.. you have your heater core connected to both the water pump and intake manifold. But what did you do with the opening on the passenger side of the radiator (below the fill cap)? This is what was ultimately supplied the heater core. There was a thermal exchange valve arrangement it supplied. Thanks!

 

The intake manifold is the supply side (high pressure). The radiator port is the return side (low pressure). The proper solution is to plug both ports and eliminate the hose. Get a plug for the manifold and a rubber cap for the radiator. The radiator port can be tricky to block, but I always have success with the rubber cap, some high-temp RTV, and two worm clamps. Don't overtighten or the plastic port will crack.

A water-pump port is normally a return side (low pressure), using the pump to draw coolant through the circuit. If you hook the intake to the pump via a hose, all of that coolant will be bypassing the radiator and will be pumped back into the block without having been cooled.

 

TPIS

 

Thanks so much for the helpful information. I thought the radiator was being fed by the lower radiator hose that taps right into the water pump. Also, I have an oil cooler ..a supply and return. What should I used to supply the oil cooler? Should i be using the fitting off the front of the intake and the return should go into the top of the water pump? Your help is appreciated!

 

Can someone please tell me what the inlet thread size is on top of the water pump? I need to get a 90 degree fitting. Also if anyone knows with the thread size is on the driver's side intake PCV fitting is. Thanks!

 

Hey OP, what are the part numbers for the two stainless parts that you used to do the coolant bypass. Thanks.

 

I'll have to look it up, but I'll get back to you soon.

 

Thanks man. It looks like the fitting on top of the water pump is 1/2" NPT. It also looks like the fitting for the PCV (lower side of driver's side) is 3/8" NPT.

 

Well everything's only 5/8" size for the hose. What changes is the thread size, thats what im really wondering.

 

Sold the car.

 

What were the sizes of the the 90 and 45 degree fittings?

 

What size is the 90* heater hose fitting and 45* heater hose fitting for the water pump

 

You do realize that this thread is 17 years old and the latest post is 16 years old, right? Watch the dates.

 

The water pump and intake port is 1/2NPT, on the newer modes the return goes to the radiator