engine comparison

[74AMX]

Alright. Lately with the way my engines been running I dont know what to do. But first things first, the guy who got this car 'rebuilt' i think got screwed. its a 401 amx, but i cant be sure the engine matches unless i find the vin numbers on the block. where are they located? if this engine isnt original, how hard is it to find a 401? Are there any big differences between the 360 and the 401 that might tell them apart from one another?

[Big Bad AMX]

To confirm the correct cid for the VIN code the cid number is cast on the sides of the block in approximately 2" high numbers, they’re located behind (above) the engine mounts. The 401 is designated by a Z in the VIN. Visually the 360 and 401 look the same so you'll need to set the parking brake and crawl under the car with a flashlight to look for the '401' cast in the block.


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[74AMX]

good post thanks for the info... its a 360 after checking it out... maybe it did get bored over but if someone were to bore it over, would they even be able to bore a 360 over to 401? it looks like a pretty small block (without having the heads off to investigate) to bore over that much. the vin also says its a jav 360 (according to the 1973 TSM, not even amx, but its got all the badges...)... still not running right though. my firing order is way off. i tried redoing the spark wires, redid the plugs, maybe im not sure on the cylinder numbering. starting from the drivers side front, being #1, it goes counter clockwise, right? now remember, im only referring to cylinder numbering, not firing order... ive got that as 18435672, one being on the outside (roughly facing towards the radiator) and going clockwise. any help for a broke *** amx-er? does anyone happen to be in clarksville with one of these that can come and help out? im getting really frustrated with this thing, and for the fact that its got 'amx 401' badges on it, it REALLY aggravates me. honestly, i wouldnt have bought it had it not been a 401. either way... if anyone can help, please post. thanks

[Big Bad AMX]

The bank of cylinders on the driver's side starting from the front are numbered 1-3-5-7 with 1 being at the front of the car, 7 being closest to the firewall.

The passenger side bank are numbered 2-4-6-8 with 2 being at the front of the car, 8 being closest to the firewall.

The firing order is 1-8-4-3-6-5-7-2 with the rotor turning clockwise (you have 5-6-7-2).

Number 1 on the distributer is located just left (driver's side) of the forward distributer hold down post. If that isn't very clear there's a diagram of it on page 9 in the Pocket Specifications Booklet that you can download for free here:
http://www.amx-perience.com/pdf/1970SpecificationsBooklet.pdf

Even though the booklet is for 1970 the tune-up specs are the same for your engine.

401's are getting harder to find but are still out there. They pop up in the classifieds section from time-to-time. The 360 will still run pretty strong though, you'll just need to get it dialed in is all. And no, you can't make a 360 into a 401.



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[74AMX]

well that made a huge difference on its idle. thanks for the tip. ill give reputation points on your responses... anyhow, i HEARD you would raise the deck with thicker gaskets and metal spacers, and then put in longer piston rods for a longer stroke, therefore making it bigger displacement, but i dont know how much that would make a difference. leaving it same stroke and raising the deck would lower the compression, making it better for turbo, but i would prefer s/c on this size engne... is lower compression good for s/c too? i guess this stuff is more related to engine and drivetrain section, if a mod wants to move it.

[do it again]

Hi, I live near you in Mcminnville. I sometimes drive through Clarksville and would like to see your car sometime. I have a 74 AMX clone that I am finishing. anci@blomand.net

[Big Bad AMX]

well that made a huge difference on its idle. thanks for the tip. ill give reputation points on your responses...
You're welcome.
anyhow, i HEARD you would raise the deck with thicker gaskets and metal spacers, and then put in longer piston rods for a longer stroke, therefore making it bigger displacement, but i dont know how much that would make a difference. leaving it same stroke and raising the deck would lower the compression, making it better for turbo, but i would prefer s/c on this size engne...is lower compression good for s/c too? Thicker gaskets can lead to blown head gaskets, in the long run it'd be easier and more reliable to find a 401. And you definately want low compression for a super charger. Too much boost with too high of compression will make things go BOOM.

i guess this stuff is more related to engine and drivetrain section, if a mod wants to move it.Moved.


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[74AMX]

So here's another good question for you. I decoded my VIN via 1973 TSM, which labels it as 360 2 door hardtop javelin 1974 (not AMX, mind you), yet everything all over the car (grille, turn signals, interior door panels, go-pak with tic-tac, etc.) say its AMX. In these years, if you wanted those tings intalled, was it an add on option straight out of the lot? Or would your VIN always reflect AMX? I hope I made that straightforward enough... I'm just confused about what route to go down with restoration.

Also, correct me if I'm wrong, but the brushed aluminum dash still had the left side rectangular cut-out right? I pulled the dash apart and found this cut-out behind a flush dash piece, which looks like an a/c vent hole but no a/c in the car. (the aluminum trim covered this hole in other words, and also covered another rectangular cut-out underneath the radio, which now has an equalizer in it, and I'm sure that's not factory.) If it will help I will post pictures, I just have to go to work at the moment.

[Javelin360]

You could order the Go-Pac from the factory. I have the Go-Pac in my car but not the Aluminum trim. My car is also not an SST so in stock form it appears to be a plain jane 6 cyl car. An A/C car would have the vent holes cut into the trim a non A/C car will not have the vent holes cut into the trim. I have a dash overlay that I bought not paying attention and it was for a non A/C car so no vent holes.

It sounds as if someone has bought all the trim for an AMX and installed it on your car. It may or may not have had the Go-Pac from the factory. There is no way to know for sure unless you are lucky enough to have forund a build sheet in the car. I found the build sheet for my car under the passanger carpet but it was so faded and deteriorated I could not read it.

I'm not sure if AMC varied any of their vin designations so here is the breakdown from a 74 TSM.

For a 74 AMX with a 401 the first 7#s of you vin should read as follows:

A 4 C 7 9 8 Z XXXXXX

A= AMC

4= 1974

C= Automatic floor shift (M= 4spd, A= column shift)

7= Javelin

9= 2dr hardtop

8= Javelin AMX or Matador X (if there a 7 in this position you have a Javelin)

Z= 401 V8 4V (N=360 V8 2V P= 360 V8 4V)

As an aside the AMX designation was only a cosmetic package for the 71-74 cars.

[Javelin360]

Another item. If you pull the Go-Pac, look carefully at the wiring harness. Cars with the Go-Pac had a wiring harness dedicated to the Go-Pac. Cars without the Go-Pac had a harness minus all of the Go-Pac connections. If your harness appears to be hacked or the wires appear to be added in then your car most likely did not have Go-Pac from the factory.

[74AMX]

alright, all good stuff, but the vin still decodes as a javelin 360... figures... It just seems like a lot of effort to put into a jav to make it look like an amx, dont you think? spoiler, badges, grille, interior door panels, go pak, (i think the hurst shifter with pistol grip was also included with the amx package) and so forth... i know alot was done to it in the way of body work, it now sits as doo doo brown, whereas underneath that its the transam red. block is ford blue, and alot of edelbrock parts scattered throughout. when i pull the valve covers, they look like stock heads, but im not sure. is there anything thats a telltale sign of stock heads? if theyre not, im garaunteed theyre edelbrock performer series, but i just cant tell myself. i think i just need to get hold of the mechanic, who just seems really hard to get in touch with. figures on that too, right?

p.s. a4m797n

[Javelin360]

alright, all good stuff, but the vin still decodes as a javelin 360... figures... It just seems like a lot of effort to put into a jav to make it look like an amx, dont you think? spoiler, badges, grille, interior door panels, go pak, (i think the hurst shifter with pistol grip was also included with the amx package) and so forth... i know alot was done to it in the way of body work, it now sits as doo doo brown, whereas underneath that its the transam red. block is ford blue, and alot of edelbrock parts scattered throughout. when i pull the valve covers, they look like stock heads, but im not sure. is there anything thats a telltale sign of stock heads? if theyre not, im garaunteed theyre edelbrock performer series, but i just cant tell myself. i think i just need to get hold of the mechanic, who just seems really hard to get in touch with. figures on that too, right?

p.s. a4m797n

74 AMX cars with autos had the same floor shifer as a standard Javelin with a floor shifter. I'm not sure about the cars with 4 speeds as all 4 Javelin/AMX cars I've owend have had auto trans.

It really isnt that much work to add the AMX stuff. The grill is a direct bolt on and the door inserts are all that need to be changed, not the whole panel. The front spoiler bolts directly on and the whale tail just requires a few holes in the deck lid. The Go-Pac goes right in and all you need to do is wire it up. The Shaker hood bolts right on. About all that is left after that is to pull the Javelin scripts and replace them with AMX emblems.

It is not uncommon to find clones. It helps for know the VIN coding before you purchase. When I bought my 74 AMX I didn't pay enough attention and later found that someone had installed a 343 to replace the 401.

I can't help with the head question but I do know that Edelbrock did make a lot of aftermarket parts for our cars. I have an old Edelbrock AMC Tourqer intake a from a 68 AMX that used to run in my area. I also have the 390 block from the car. Sadly the body was totaled in a rollover accident.

You have almost the same car I have. You have the manual tranny and I have the auto. Is your car an SST?

[74AMX]

lol, not to my knowledge. everything to me looks like just a 360 javelin with the 4 on the floor. i couldnt really tell you much about anything else because this is the first time ive actually seen a javelin and its the first time ive dealt with one to own or tinker with. other varieties of cars i have knowledge for days, especially after fuel injection came into cars, but carbs are still a little grey area to me. I guess the long and short is, no idea if its an sst. i would imagine no, but i have no idea what to even look for on that either to know yes or no.