65nassau

Would anyone using a ZZ series engine chime in on their brand / model of Spark Plugs please?

These are great engines, but finding info on them is not that easy. You get a blank stare at most auto parts places.

I'm also interested in proper torque specs, as I dont want to damage the aluminum heads.

JAF1

I am positive they are listed on the spec sheet for each crate engine. Check out GM's site or anyone else that sells them.

Cruzmeisters

See if you can get info from web site: www.paceparts.com
Cruz

sjaroslo

I have a Fastburn 385 that is based on the ZZ4 short block. Interestingly, the spark plugs called out for the engine by GM are MARINE spark plugs--the local Kragen and AutoZone don't carry them. But the local boat supply joint does....

sjaroslo

My Fastburn 385 crate engine, complete with standard Vortec aluminum heads, interestingly takes a MARINE spark plug. The local Kragens and AutoZone don't carry it. But the local boat supply joint does....

ffas23

I have what I guess is the original of the Z series engines powering my Street Rod. Its identification code is ZZZ. It was purchased brand new in 1989. It is a 350-345 hp engine and it uses AC Spark plug FR5LS and takes a .035 gap. This engine was fired up for the first time in Oct. 2003.

JohnZ

The Chevrolet Power Book calls out 15 ft-lbs. for tapered-seat plugs in aluminum heads, and be sure to use anti-seize on them so you don't pull the threads out of the head the next time you change them.

65nassau

Thanks for the help. I'll get the anti sieze compound and verify thru pace that FR5LS is the correct #. I'll have to call them to check it, the website is no help on that.

ffas23

I still have GM paper work from my engine that shows this information and AC FR5LS is what it says. When I purchased my engine it was still in the crate never taken out. I purchased it from a fellow in 92' who never got to put this engine in his SS Nova like he planned to do. I paid $2100 for it never fired. It sat in my Street Rod project until I finally fired it up in Oct. 2003 like I mentioned earlier. FR5LS are the plugs sitting in the angle port heads of my engine and as of right now there is less then a thousand miles on it.

JPB04619

i have an unfired 94 zz3 on a stand in my basement. plugs are mr43lt....john b

65nassau

Now there's a question that needs answering..whats the difference between those 2 plugs?

If I remember correctly, I think I have the MR43LTS in mine as well and wondered why they were there and if they were indeed correct.

I'll do further checking and appreciate your responses.

ffas23

Like I said earlier my engine is probably the original ZZ motor Chevrolet came out with. It has the code ZZZ. The original GM part number for my engine is #10134338 and it came equipped with AC FR5LS plugs. I have the paper work to prove it.

Fred

FreakinVette

I have a ZZ2 engine (ZZZ to ZZ3 all same) and use the AC DELCO FR5LS plugs and gap @ .04.

I’ve also found Autolite 3926 work great too as a replacement with same gap. Anyone else use these???

silver837

You are answering a 17 year old thread.

ffas23

It’s ok with me I am still around to read it and still have my Street Rod with my ZZ4 Series Crate Motor. Still has the same AC Spark plugs in it that it came with in the factory GM crate as mentioned above.

JCOOP

ZZZ motor in my 66. Installed 1993. Good motor still running strong. Wake up 17 year old thread.

ffas23

That engine was the perfect replacement small block for your car. I really like mine. I have a 87SS Monte Carlo I am hoping to finish restoring. Wish I had another ZZ4 Series Engine to install in that car.

cv67

ooh pics of the monte!!
Friend put a nasty 383 in his when it was 6 mos old..nobody knew about tuning a TBI engine back then. Never ran right
GM has cancelled or upped price on so many crates..

FreakinVette

JCOOP, cool spark wire looms which fasten to the valve cover 👍 😎 I wanna do that on my car!

Where did you get those?? Do you like your MSD ignition, wires and did you upgrade the coil?

troutster71

I’ve also found Autolite 3926 work great too as a replacement with same gap. Anyone else use these???[/QUOTE]

I installed a '90 Corvette L-98 in my '67 in 1991. As I recall it used Autolite 3926 plugs. Tweaked that engine a bit in '15, and now uses 3924 Autolites. Bigger cam, more compression, ported heads. One step cooler plugs, runs great!!
Cheers! Gary
Hello zombie thread!!