521 Radiator upgrade?

[domn8tr]

My 521 w/ L20b I recently purchased from SDSurf runs hot and on shutoff detonates then runs backwards. Is there a common radiator upgrade? He gave me a volvo radiator but it looks like it will only fit in sideways and has no filler cap. I set the timing at 10 degrees is there a possibility the cam is off a tooth? if the motor is not hot yet it shuts off with no gasp but I cringe everytime it does it. I'm looking at installing a z car waterpump and have ordered the larger capacity oil pump to go with my spraybar valve cover. I'd like the motor to run cool and be bulletproof since summers coming and I don't want to warp my peanut head!

[banzai510(hainz)]

A Z car pump needs a different fan I believe. Its not going to fix it. Pumping more water and the stat is closed isnt going to do anything. it dont take much to move the water once the stat is open. I bet the stat bearely open most of the time in a working motor.

 

 

maybe clean the radiator out. or get it cleaned.

I would try a 54mm stat. in 160deg and drill a 1/8 hole on it. this will work on the cooler days but if its hoot outside it will still get hot.

 

 

as for the desieling ,run on this has been dicussed 1 million times already last week about L20s and weber carbs. Its a open chamber head they do that with cheap gas and really need a cutoff selinoid for the idle jet. Thats if the weber will take one and youll wire it to the eleltric choke.

Buy some some Super and retard another 2 deg and see what that does.

 

YOU SURE THIS IS A PEANUT HEAD?

 

 

My 521 has run on and it dont even get hot but has a U67 head with L18 block.

what I do is i shut the key off and rite before it wants to RUN ON I hit the pedal to open up the butterflyes and hope it stops running. I have a 38/38 so I loss more vaccume

[datzenmike]

My 521 w/ L20b I recently purchased from SDSurf runs hot and on shutoff detonates then runs backwards. Is there a common radiator upgrade? He gave me a volvo radiator but it looks like it will only fit in sideways and has no filler cap. I set the timing at 10 degrees is there a possibility the cam is off a tooth? if the motor is not hot yet it shuts off with no gasp but I cringe everytime it does it. I'm looking at installing a z car waterpump and have ordered the larger capacity oil pump to go with my spraybar valve cover. I'd like the motor to run cool and be bulletproof since summers coming and I don't want to warp my peanut head!

 

Dieseling is caused by heat in the air being concentrated by the compression of the motor. If there is enough heat it will detonate by itself without a spark.

 

Connect some dryer hose to the snorkel on the air filter housing and draw cooler air from in front of the rad. The air around the engine can be 200F.

 

Be sure the heat shield is in place under the carb to reflect radiated heat from the exhaust manifold.

 

Check that you are running the proper heat range NGK plugs.

 

The cheapest easiest cure is to hold the brake down and lift the clutch slightly to load the engine, then turn the ignition off. The motor stalls immediately. Don't lift the clutch all the way until the motor stops. A little practice and you won't even know you are doing it.

[domn8tr]

The head is an A87 that the guy who sold my son his 510 said had about $1000 (Ya Right!) of port work and triple angled valves we measured the ports at 1.45 ,Bout the same as 2 liter ports I think. I did put in the cam from the 2 liter in . I should probably check to see what my compression is. The carb is a manual choke weber 32/36 with the weber open filter element. When I bought the truck From SDSurf the water outlet (inlet?) on the intake manifold was blocked off so i reconnected it. It doesn't have a heat shield like my roadster but fabbing one up would be easy. I think Redline makes an adapter to put on a stock airfilter. I also have a matchbox Dizzy and coil I intend on installing . When i do that I'll try pulling the timing back to 5 deg. Will i need to upgrade the alternator with the Matchbox setup? Should I consider removing the thermostat altogether? I know on my RZ350 that is not a good idea as it slows down the coolant movement so it can pick up the heat from motor better.

[banzai510(hainz)]

SDSurf has been on here awhile.

I wonder if the water line was plugged for a reason. The head might not have water ports thats why he plug the line thats by the fuel pump right? So hooking it up wont do anything beside make a place to leak water.Usuall there is a meatal water line then a small hose to the intake.

 

there is a weber carb adapter for the stock air cleaner but I notice it raises the aircleaner up and depending on what carb adapter might hit the hood esp with a L20.Best to get the short aircleaner. 1.75in Mike Klotz did a nice HOW TO on taking the stock aircleaner and weling a sheet metal plate then cutting out the Weber DGV outline. Its nice and alot less noise.

 

as for the 5deg timming? nothing stopping from setting it back 5 deg now.

 

The matchbox conversion is n the "HOW TO" section

 

Removing the state is not recommented but you can try and see if it still gets hot then you know soemthing is bad.