Billet freeze plugs/bypass

Gorms

Gorms

New member
Popped the rear plug today on way to work, fun. Happened during a spirited run through 3rd gear. Not sure if maybe I didn't set it properly on install, has been completely leak free for 5k miles since I freshened up the motor. Head and block were properly cleaned before I assembled everything, all coolant plugs were lock tighted in, none have leaked until today. (It completely popped out).

I'll be replacing it with a bolted version for sure, just wondering if it is worth it to do the bypass kit? Truck is just a fun daily now, might hook a camper behind it a few times this summer. Not sure what it makes for power, does brake traction in any gear though if not careful. 3k rpm for now, 5x12s, 215pump, and he351/ht60 making about 60psi on close to stock timing.

Truck was not very hot when it happened, just got off highway in 20 ish degree weather, cooled down some between stop lights probably.
 
More than I should, just about every day I drive it.

I figure its the best way to find the weak links while close to home. I go easy when more than 200 mi from home.
 
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Currently have 3k springs in it, I regularly hit 3k. It seems to defuel starting at 3200, I haven't seen much higher than that
 
I’ve read some threads about the pressure relief vs temp relief. I’ll try to find it. I’m pretty sure I read it here.
 
Make sure the truck is thoroughly warmed up and several thermostat cycles. IMHO what happens, block/water gets up to temp. Thermo cycles, lets cool water in, hits the freeze plug, plug "shrinks" just a little, and pop! Out it goes. You can also drill a few holes in the thermostat. Also I used a water pump off of an industrial application, it had a larger pulley so it ran slower at a given RPM, trimmed the fins, never had an issue and my truck saw 5000 RPM several times.
 
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I've also done the trimmed water pump with good results, and still towed heavy in the summer without getting hot.

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I dont plan on hitting 5k, but was going to throw in the 4k springs and bump timing to 20 or so degrees,, now that its good and broken in.

Ordered a Keating plug with the threaded plug in it. Where would that get routed to to help with excessive heat/pressure?
 
I run a bolted rear plug with no bypass on my race truck with 0.300" trimmed off diameter of water pump fins. Hit 5000+ rpm many times with no issues.
 
Vincejax said:
I run a bolted rear plug with no bypass on my race truck with 0.300" trimmed off diameter of water pump fins. Hit 5000+ rpm many times with no issues.
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So the rest of the plugs are stock or billet block plugs as well? I’ve heard the ones on the head can be a problem too?
 
bateman said:
So the rest of the plugs are stock or billet block plugs as well? I’ve heard the ones on the head can be a problem too?
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Rest of plugs in block are also bolt in. Still have stock press in plugs in the head. I have blown the plugs in the head before trimming water pump, no problems since.
 
I did a bolt in with a -4 line running from it up to the heater line. Everyone used to complain that a full 5/8” line would make it take forever to warm up because it was bypassing so much. So I figured a smaller line will still bypass some but not enough it take a long time to warm all the way up but still give a place for excessive pressure to go.
 
How are you getting at that rear plug? pulling the trans back?
This is something Id like to do, but have never had a plug fail. Maybe just leave it alone.
 
I used a bolted billet plug and a Watts Valve set around 50psi that bypasses to the upper radiator hose with 5/8" heater line. Supposedly the fringe benefit is that it allows more coolant to flow around the rear cylinder at high rpms keeping it from getting as hot and pinching the rings like we've seen so many times. Spins to 5k no issues and when i tore it down #6 looked perfect.
 
I was thinking of running a regular 5/8 line back to the extra nipple I had below the oil cooler, from when it was an auto. Would that be on the right side of the cooling system?
 
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