ZLX question

[Schonyenko2]

I looked at a survivor (well almost) X22 69 camaro today.Was an original 396, don't know the hp rating, but was blown up early in it's life. It had what was described as a ZXL 427 installed at the selling dealer by paying over what the warranty cost of the 396 was.(not uncommon back in the day).The rest of the car was undisturbed although he claimed they changed the factory ordered rear gear 4.88 to a 3.31. Turbo 400 floor shift. Original HO, narrow rear spoiler that appeared original, and had the larger torsion rod. Was also a factory cowl induction hood option.
This question has been asked before, but I don't remember a definitive answer. What was the true story, and specs on these supposed to be ZLX CE motors. I've heard the term cast iron ZL1, but there were no open chamber cast iron heads until 71 that I'm aware of. I see nothing about this motor in Colvin's books. Explain please. http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif

[ORIGLS6]

I recall an article about Baldwin/Motions ZL-X option but I thought it was something they built at Motion. You're thinking this was something GM offered?

'Cast Iron ZL-1' rings a distant bell too.

[firstgenaddict]

Thought it was Motion that did the ZLX's... KevinS had one then it was for sale on Ebay last year ... was a day 2 car... Z28 if I recall then converted in like 74...

[Xplantdad]

After Kevin owned it...Andy (quick-bowtie) owned it...

[Schonyenko2]

I have seen Nickey sales slips showing ZLX motor assemblys on this site. Joel talks about his ZLX motored cars many times in the magazine articles. The ZLX in this car was sold locally. I'm sure they exist in maybe more than 1 form.What I want to know are the part numbers for the short block, and the rest of the motor. This one does show a CE ft pad stamp. I don't think these crate motors existed before 71. Joel talks about them before that. He once told me he got the heads out the back door of GM. http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif

[Musclecarkid]

Found this in my Motion Performance Guide (copyright 1976)

"ZL-X...427 cubic inches, 650HP, solid-lifter .585-605 PHASE III cam, choice of gear- drive injected, 850, 950, or 1050 cfm Holley carburation on reworked aluminum high-riser, cast iron open chamber heads with special 12.8 to 1 pistons, 69 L-88 blueprinted four-bolt main block. This is a very special M/P competition engine."

IMO, I believe this was a crate motor from GM that Motion tweaked on a little.

Similar to an iron head, open chamber L88 or ZL1 with a cam change and blue printing.

I believe the ZL-X iron open chamber heads were 026's available in late 70 or early 71 as an over the counter piece. They were replaced by the 990's around 72-73 and used till the mid 1990's.

The ZL-X heads were used on 427 and 454 engines according to this catalog.

[Schonyenko2]

I agree. Somewhere though, there must be a reference to ZLX in a Chevy service parts book. The counter guys at Nickey, and Ericksen's where this motor was installed weren't pullin the designation outta thin air.

[ORIGLS6]

Ken, check your e-mail.
I have an article from the April '72 issue of Hi-Performance CARS, featuring a '72 Chevelle with the ZL-X option. Also in the October '71 issue are ads from M/P showing the "Super Trick Open Chamber Cast Iron Heads" (Racer's Net... $395./pair). It shows a M/P Part No. of 3946028-70....... maybe NOT a GM number! (but worth checking)

Also a Complete 427 inch ZL-X engine for $1395.00 and the 454 version for $1995.00. http://www.yenko.net/ubbthreads/images/graemlins/eek.gif

[markjohnson]

The mysterious ZL-X. I believe musclecarkid is correct about the 026 cylinder head being the correct ZL-X cylinder head. I had set on a motor about 15 years ago with '1971' casting dates on them and had always wondered what their original application would have been. In 1971, the only rectangular port cylinder head being used for assembly line production was the '074' aluminum head on the very rare 1971 LS6 Corvettes. I just concluded that it must be an over-the-counter cast iron, open chamber, rectangular port cylinder head used for crate engine or even a service replacement if someone wanted to use cast iron heads on an L-88 motor in marine application. The 026 was the forerunner of the common 990's and 188's that would be used on LS6's and LS7's for the next couple of decades. By the way, the 427 I had these on was really a runner!

[68l30]

Didn't Joel discuss this at the SCR Banquet? I have the tape at home....He mentions something about them being nothing more than a GM part number with his marketing crew making up the ZL/X name.....I remember him thinking this was funny...I know I did.


Steve

[69SSZL1]

From page 150 of vintage "How to HotRod Big Block Chevys" in the Heavy duty parts list they show chevy part #3970699 as a partial engine assembly L-88 427: "430 HP L-88/ZL-X short block with 12.5:1 c.r. pistons for use with open-chamber heads, 4-bolt mains." I still dont know what ZL-X refers to.

[Schonyenko2]

I went and found my old copy of that book. Mine may have been an older edition as there was no mention of the ZL-X. But in the process of looking for it, I came across my old Nickey, and Berger catalog, and they both list it. Berger:1/2 engine assy/short blk, 0699 427/430 ZL-X 12.0 to 1 open chamber. 1/4 engine assy: fitted blk 8656 427/430 ZL-X 12.0 to 1 open chamber.
Nickey's reads: 9960 427/450 12 1/2 floating wrist pin, 4 bolt solid cam ZL-X L88 open chamber. I think they may have the part# backwards.
So it basickly is, with 026 open chamber heads, a cast iron ZL1.
It appears this was kinda the transition/ evolution to the LS7 454 crate motor.

[Geo]

I bought a ZLX in 1969. First I ordered the short block, and then I ordered the ZL1 Aluminum Open Chambered Heads which took 3 Months to get due to having to wait for them to be produced. The heads came bare so I had to get all the parts to complete plus I had them CC'ed. This engine is the same as the ZL1 except that the block is cast. ZLX is the ZL1 with a cast block. I put the engine in my 1966 Chevelle SS which I still have. The car has been stored most of the time sense 1973 due to me being stopped by the police. I used to street race and the car got to be known and that's when the police starting pulling me over just because they knew the car. I always run the engine every so often. I had the engine gone through installing all new bearings. It has maybe 1500 miles on the engine. When I ordered the engine Chevrolet called it a ZLX and that it was identical ZL1 but had a cast block.

[Geo]

Here is some info I found online about the ZLX 427

The most famous version of the 427 was undoubtedly the 1969 ZL1 engine. Developed for Can-Am racing, where it was very successful, the ZL1 had specifications nearly identical to the production L88 version of the 427, but had an all-aluminum cylinder block that weighed 100 lb less than a similar iron block. The engine was also fitted with the new open combustion chamber cylinder heads, a lightweight aluminum water pump and a specially tuned aluminum intake manifold, resulting in an engine weighing little more than a small block, but producing around 600hp in "street" tune and far more in racing tune. The 4718 dollar cost of the ZL1 option doubled the price of the 1969 Corvette, but resulted in a car with exceptional performance. Just two production Corvettes (factory) and 69 Camaros (non-factory option COPO 9560) were built with the ZL1.

Chevrolet capitalized on the versatility of the 427 design by producing a wide variety of high performance, "over the counter" engine components (marketed as "heavy duty" or "extra capacity" components to mask their intended racing application), as well as ready-to-race "replacement" engines in shipping crates. Some of the components were developed to enhance the engine's reliability during high RPM operation, possibly justifying the use of the description "heavy duty." However, most of these items were racing parts originally designed for Can-Am competition that found their way on to dealers' shelves, and were meant to boost the engine's already impressive power output. As a result of this activity, the 427 quickly became dominant in drag racing.

The version of the 427 produced from 1966 to 1969 was fitted with essentially the same cylinder heads as used with the 396, a type often referred to as the closed combustion chamber design. Starting in 1969, the highest performance models were fitted with the new open chamber cylinder head, which along with design improvements in crankshafts, connecting rods and pistons adopted from the Can-Am development program, resulted in an engine with substantially increased performance and reliability. This development culminated in a specialty version of the engine called the ZLX, which was essentially a ZL1 engine built with the L88 engine's sturdy, four bolt main bearing iron block (it has been suggested that "ZLX" was a code name for ZL1 crossover). The ZLX, available as a short block assembly or complete "replacement" engine in the crate from a few dealers, was a resounding success and became a best-seller by after market racing components standards—the closest thing to an all-out competition engine ever offered to the general public. Chevrolet gave all 427 engines except the ZL1 a torque rating of 460 ft·lbf (624 N·m).

[copo-2]

Motion Performance shows different options for the ZL-X from their 71 catalog?


http://i211.photobucket.com/albums/bb303/DH427Nova/MotionsRacingEngines1.png


http://i211.photobucket.com/albums/bb303/DH427Nova/MotionMailOrderMotors2.png

My 2 cents... <<GRAEMLIN_URL>>/wink.gif

I went through my old Chevy Special Equipment manual (the green page book) with a publication date of 3-9-72. I couldn't find any mention of the ZLX. There is, however a part number for the cast iron open chamber rectangular port heads, and of course, a part number for the second design L88 (when combined would obviously make the ZLX). My take on this has always been that Joel &amp; Company @ Motion coined the phrase, advertised it and the rest of the people in the biz picked up on it. In the end, I think it was pretty clever. I'd still like to get one for $1995 though...L-O-L

Wayne <<GRAEMLIN_URL>>/beers.gif

[SUSQ]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Hotrodsled</div><div class="ubbcode-body">My 2 cents... <<GRAEMLIN_URL>>/wink.gif

I went through my old Chevy Special Equipment manual (the green page book) with a publication date of 3-9-72. I couldn't find any mention of the ZLX. There is, however a part number for the cast iron open chamber rectangular port heads, and of course, a part number for the second design L88 (when combined would obviously make the ZLX). My take on this has always been that Joel &amp; Company @ Motion coined the phrase, advertised it and the rest of the people in the biz picked up on it. In the end, I think it was pretty clever. I'd still like to get one for $1995 though...L-O-L

Wayne <<GRAEMLIN_URL>>/beers.gif

</div></div>

Adjusting for inflation using the Consumer Price Index, in today's dollars you could pick one up for $10.784.65. Money well spent, indeed!

[Citation_sp]

In engineering terminology &quot;X&quot; usually means cast iron. so ZL-X could just be GM's way of stating cast iron components.

[Tracker1]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Citation_sp</div><div class="ubbcode-body">In engineering terminology &quot;X&quot; usually means cast iron. so ZL-X could just be GM's way of stating cast iron components. </div></div>

I don't believe GM/Chevrolet ever used ZL/X in their sales pieces. As mentioned, it isn't in the green sheets book. I agree it's a Motion term that was popularized by Chevy parts guys in the know.

[EZ Nova]

So WHAT intake would be considered &quot;correct: for a ZL-X motor? I see above, the 600Hp 427 is a tunnel-ram, so what would the other 4427/550Hp motor come with??? GM or aftermarket intake?

[markjohnson]

I'd say a GM #198 open plenum dual plane. Same as a standard ZL1.

[EZ Nova]

That's my thoughts too. I've been searching the internet and only coming up with tunnel ram info. Seems like some had the Edelbrock TR-2X but the '69 Camaro's had a tunnel ram with ribs on the floor of the tunnel ram and D ports under the carb????

[EZ Nova]

So after some research, I think I found out a few things:

Also noted in the listing is the you COULD get a 480&quot; version for Marine???

Heads seems to be a bit confusing? Seems &quot;originally&quot;, you would get the 026 heads, and later the 990's. BUT seems like you get order the ZLX short with 074 heads! As was seen on Kevin's '69 Z28 ZLX conversion.

As for the intake, seems the #198 intake was on the engines UNLESS you went to the FULL COMPETITION top-of-the-line Hp rated engines, THEN it looks like you got a Weiand Tunnel ram.

MUSCLECARKID, you posted an piece for your 1976 Motion Performance Guide, and it shows a ZLX427 with 650Hp. I wonder what the ZLX454 and ZLX480 made? If the 427 was 650, just using the cu/hp formula, the 454 should be about 490 and the 480 should be around 730!! Wonder if any of those made there way into a car????

LOOKS LIKE ONE WILL NOW THOUGH!

[SS427]

Picture taken when Kevin S. owned it.