ZZ3 Chevy engine question
 

Sorry this is a little off the forum, but ZZ3's could be used in a smaller boat. A lot of you folks on the board have hot rods, is anyone running an over - the - counter Chevy ZZ3 smallblock? This is the forged steel connecting rod version of the ZZ4.

The question is, what spark plugs are you running?

Re: ZZ3 Chevy engine question
 

MY partner ran a pair of ZZ3 's in 27 Hallet ran great for approx 350 hrs until replaced with 383's...never a minutes trouble with the crate motors

KL

Re: ZZ3 Chevy engine question
 

I try to run NGKs in everything.

Re: ZZ3 Chevy engine question
 

Hi Ed - I agree on the NGK's but what I'm looking for here is a plug #.

Re: ZZ3 Chevy engine question
 

Aha! Okay, but I need more info.
Tell me what plugs are in there now, or do the heads need 3/8" or 3/4" reach threads.
You can get extended electrodes or not depending on application and usage.
The more info you have, the better I can get you in the right ballpark with the plug that will give you the best service in real-life conditions.

Re: ZZ3 Chevy engine question
 

Thanks Ed. Thats part of the problem, the engine was a takeout from another Vette that I bought and I don't trust the guys that put that car together. The engine had NGK TR5 V - Power plugs, BUT are they correct?. The heads are the late model aluminum angle plug Chevy heads that come on the over the counter engines.

Re: ZZ3 Chevy engine question
 

Here's the spec section for ZZ-4, including plugs. I don't have a ZZ-3 in my catalog.

-Greg
HO 350 SPECIFICATIONS
Part Number: 24502609 (ZZ4)
Displacement: 350 cu. inches (5.7-liter)
Horsepower: 355 at 5250
Torque: 405 lb-ft at 3500
Bore & Stroke: 4.00" x 3.48"
Compression Ratio: 10:1
Engine Block: Cast iron with 4-bolt intermediate main bearing caps
(P/N10105123)
Crankshaft: Undercut and rolled fillet LT4 nodular iron crankshaft.
Connecting Rods: Steel P/N 10108688
Pistons: High silicon aluminum piston with offset pins (P/N 10159436)
Piston Ring: 14089025
Camshaft: Hydraulic roller tappet (P/N 10185071)
Valve Lift (Intake/Exhaust): .474"/.510"
Duration (Intake/Exhaust): .208/.221 degrees at .050" tappet lift
Valve Lash (Intake/Exhaust): Zero/Zero
Cylinder Heads: Cast aluminum, 58cc chambers, angled spark plugs, screw-in
rocker studs (P/N 12556463)
Intake Valve: (1.94") P/N 10168465 Exhaust Valve: (1.50") P/N 10168514
Valve Springs: LT4 chrome silicon 1.340" diameter (P/N 12551483)
Rocker Arm Ratio: 1.5:1
Distributor: High Energy Ignition with centrifugal and vacuum advance (P/N
1103436)
Initial Spark Setting: 10° BTC @ 800 rpm with a maximum of 32° at 4000
rpm with vacuum advance disconnected.
Spark Plugs: AC FR5LS, 904, or MR43LTS
Maximum Recommended Engine Speed: 5800 rpm
Fuel Requirement: Premium unleaded (92 octane)