Water neck

[NixVegaGT]

Will this work on my intake?

http://store.summitracing.com/partdetail.asp?autofilter=1&part=MOR%2D63420&N=700+4294872710+115&autoview=sku

[hoffbug]

Is there a reason you want a filler neck above the thermostat?

Is your radiator way lower then the height of the manifold?

[NixVegaGT]

LOL. no. It's about level. It's a no access rad though. SO I need a way to fill it. The other thing I was considering was an expansion tank. Maybe I could mount it above and behind the engine on the firewall or something. Opinions? Here's another thing; With an expansion tank do you use an overflow? Or just don't fill it all the way? I've never used one.


Thanks team.

[ex-tyke]

What you're proposing (with the Summit fill neck) should work just fine. The small overflow hose should route to an overflow bottle/expansion tank (similar to the original MGB brass overflow) which is a non-pressurized vessel...ie. there is no pressure cap on an overflow tank. As the engine cools, water is drawn back through a small valve in the pressure cap to replenish lost coolant.
On the other hand, a surge tank is a pressurized vessel that is generally mounted high in the cooling circuit and is also a venting device for entrained air that develops in the cooling system (generally the highest point in the engine and the radiator) - this is not what you want in your case.
Edit: One more thing - initial engine coolant fill is done through the pressurized rad cap  - you cannot fill through the expansion tank

[Moderator]

I agree with what Graham said, except possibly "this is not what you want in your case..." - For a street car, I prefer a regular water neck on the engine and a pressurized transparent vessel (from a European car such as Volkswagen, Volvo, Saab, BMW, etc.) mounted on the firewall. I've used a system of this type on my MGB for many years. I find it reassuring to be able to see the coolant level at a glance. The bottle will have a coolant level line marked on it.  Don't fill coolant higher than that line or the system will puke the excess. (I've done that.) Of course the system will also puke coolant if you way overheat the engine. (I haven't done that.)  

This shows a VW Jetta header tank and my old radiator and vent lines.
(I'll have a new photo with different radiator and vent lines soon.)


My VW bottle has little vents in the bottom of the cap. That might not conform with racing rules... but other tanks/caps are apparently available with an overflow port, like this photo apparently shows:  

http://www.oeveedub.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=oe&Category_Code=vanagon-cooling (Note the price... $22 for a brand new pressure tank!)

(I haven't actually inspected this bottle in person. I just came stumbled across it and bookmarked the link.)

[hoffbug]

Ahh.. OK.. I guess I was thinking of the air lock situation my friend had with the newer LT-1 he installed in his 69 Chevelle.. He had to run an expansion tank above the filler neck to properly fill the block and radiator.

[NixVegaGT]

That is great! I think I'm going to go with the expansion tank on the firewall idea. Thanks for pitching in, guys.

ON another note, Curtis. Did you fabricate the plenum housing on your carb? Do you think it flows enough for 5.0l?

[Moderator]

On another note, Curtis. Did you fabricate the plenum housing on your carb? Do you think it flows enough for 5.0l?

I've only "tested" it with my own 3.5L engine... so I can't answer about your much higher flow rate. Area at the narrowest cross-section measures ~5.5 square inches. (The section is a symmetrical trapezoid 1.375" tall with a 4" wide base and a 3.675" wide top... but deduct a little for rounded corners.) Did I fabricate it? No, my friend Ashley Dudding did. He was helping me with the conversion, and one night we had a friendly competition. He created that "cobra head" in one night, and I created the aluminum air cleaner housing the very same night. I think his design is a little more elegant, plus he really did make deadline. I took the aluminum air filter housing to a professional welder the next afternoon and him lay down pretty beads with a TIG welder.

The air filter might also be a little small for 5.0L race motor. (It's from a 3.0L Ford Probe.)

[NixVegaGT]

Thanks man. I'm just trying to ideate a concept to get cool air into the engine. I know a number of injected cars use like 4" tube and it works OK. I found a plenum that has a 4" inlet but it says it's max airflow is 4.0l. Hmmmm.

I guess I've got to see if the engine fits under the hood before I get too far. LOL. Thanks for the input.

[Bill Young]

Nick, I saw these on Two Guys Garage a couple of weeks ago. I looked them up on line, the low profile unit flows 675cfm the high top unit flows 900cfm. Unless your engine is really built for drag racing I'd think the 675 cfm unit would do ok for a 5.0.
http://www.powerflowracing.com/catalog/catalog01.pdf

[Moderator]

Wow. According to that link, a cold air induction system can provide a 27 percent horsepower and torque boost on a 60 degree F day. Wouldn't it be nice if that were true!

[Moderator]

As promised above, photos of my updated/simplified plumbing have been uploaded here:
http://www.britishv8.org/MG/CurtisJacobson.htm

Example: