74 javelin
I have a 74 javelin with a stock 360 and want to get into bracket racing up here in WA. I'm hoping to break into the 12's but don't know how much hp/torque this is gonna take. I'm looking for some sage advice and a plan of attack to get from here to there.
fifesjeep
Better build up more than the engine. :idea:
What is your max dollar amount?
Speed costs money... :-| 12's really isn't that fast.
tufcj
12s will depend on weight, gearing, traction, and HP. The Jav is a pretty heavy car, so 12s is going to require 450-500 HP at stock weight. That's going to be a healthy build for a 360. There are ET calculators online.
My 69 AMX with a 390 is putting 325 HP to the ground (about 400 at the crank), and I run high 13s with sticky street tires.
Bob
tufcj
74 javelin
I read the two posts and need to give a little more thought to what this car is going to be before I set out to get there. First and formost it's going to be my daily driver (and it's fifty miles round trip) Going out to the track and flogging the thing sounds like lots of fun, but 8 mpg just isn't going to get it.
Can I make 400 hp at the crank and still get 12-15mpg, or is this unrealistic? The 69 amx running high 13's puts me somewhere in the mid 14's as heavy as this thing is (3900 no driver!) I'll get back with the info on the tranny and rear end this evening.
It's nice to be in the neighborhood, and I'm looking forward to all the helpful advice.
fifesjeep
Just get a hornet :t:
74 javelin
what kind of performance ccan I expect to get out of a set of poorted heads vs a set of aftermarket heads? I know that the aluminum heads are going to set me back around $1700 -$1800 but I really haven't a clue as to what a machine shop is going to charge to port my heads. I'd like to find a good shop in western WA. that specializes in amc/jeeps and knows what they are doing, rather than taking the heads to just any old machine shop that does chevy and ford heads all day long.I think that the extra money will be a good investment in the long run.
Also, what's the proper way to go about raising the compression to around 10:1? I think that's about the limit on 92 octane gas, isn't it? Different pistons, shave the head/intake,thinner size head gasket, or some combination of all of the above?
tufcj
It's been shown that a well ported iron head will flow nearly as well as an out of the box Edelbrock head until the valve lift nears the .600" range. I don't know what an aluminum head weighs, but the iron ones are about 55 LBS each. There is definitely a weight savings. Because the aluminum heads dissipate heat better, you can run a little higher compression without pinging than iron. I run the 1970 only 291C casting heads on my 390. They've been shaved about .015" and ported/polished. I think the port/polish ran about $600, plus the cost of stainless valves, hardened seats, valve job, new springs and retainers, I have around $1000 just in the heads.
The only way to raise compression to 10:1 is new pistons. Stock is about 8.25:1, the 291C heads will get you about 8.75:1, thinner gaskets and shaving give minimal increases. If it's a high mile motor, you'll probably want to bore it to clean up the walls. Bulltear sells some nice 360 pistons. You'll need to know if the block will be decked or not before ordering to get the compression height right. I'm running Ross forged pistons in my 390 Stock compression height since my block wasn't decked. They give me about 10.1:1 compression, and it will ping on 92 octane if I'm on it hard. Most AMC pistons will set you back $500-750 a set.
Old Rugged Crosser
Newbe,
I agree with Bob and what he said about the cost involved in the head work you inquire about. I just went through that very same process with the same heads and I also have close to $1000 in them and I did my own porting. Go back through the engine forum and you will find my posting with pictures on my heads.
By the way newbe, I live close to Linwood. Where about in western wash do you live. I figure we must be pretty close to each other. I do know a machinist who has a very nice machine shop at his home which is out in the country. He did my work and does excellent work. His prices are very reasonable.
If you would like more info PM me. :sa: :sa: :sa:
amcjunky
[quote=tufcj]It's been shown that a well ported iron head will flow nearly as well as an out of the box Edelbrock head until the valve lift nears the .600" range. I don't know what an aluminum head weighs, but the iron ones are about 55 LBS each. There is definitely a weight savings. Because the aluminum heads dissipate heat better, you can run a little higher compression without pinging than iron. I run the 1970 only 291C casting heads on my 390. They've been shaved about .015" and ported/polished. I think the port/polish ran about $600, plus the cost of stainless valves, hardened seats, valve job, new springs and retainers, I have around $1000 just in the heads.
The only way to raise compression to 10:1 is new pistons. Stock is about 8.25:1, the 291C heads will get you about 8.75:1, thinner gaskets and shaving give minimal increases. If it's a high mile motor, you'll probably want to bore it to clean up the walls. Bulltear sells some nice 360 pistons. You'll need to know if the block will be decked or not before ordering to get the compression height right. I'm running Ross forged pistons in my 390 Stock compression height since my block wasn't decked. They give me about 10.1:1 compression, and it will ping on 92 octane if I'm on it hard. Most AMC pistons will set you back $500-750 a set.[/quote]
with dished pistons and 291c heads will give 9.5:1 comp.
and my javelin is striped down alot yes but last year i worked it out to 430 crank hp and my car weighed 2850 with me in it race ready and ran 11.33 at 115mph with a 1.52 60 foot
tarior
Where abouts in WA do you live. I might be able to get you going in the right direction.
74 javelin
living in Port Orchard...5 to 10 minutes from Bremerton Raceway!
tarior
I'm down in Kelso, about 2 hours south of you.
My thought here is to take your stock motored Jav out and start racing it. Learn to drive it and improve your times little by little.
BTW, if you can make it, there is a big event at my "home" track on the 25th and 26th of Sept. If you show up, there will be at least 3 AMCs out there.
[url]http://www.riverdaleraceway.com/index.cfm?fuseaction=Front.Company&page_name=Drag[/url]
74 javelin
Starting out stock is probably the most economical way to go, maybe not in the long run, but if I pull the engine and get the machine work done on it and put the pistons in, then I can add the heads, cam, intake, etc... without having to pull the motor out more than once, right? Can I install headers with the motor in, or should they be installed when the motor is out at the beginning?
Since the target is around 400 hp. will forged pistons and crank be necessary? Do forged parts increase the life of the engine? What about springs, valves, and push rods, etc. do they come in hardened steel or some other similar material. I'd much rather spend the money on quality the first time, than have to go through this again sooner than later.
Are there any bench dyno programs out there that I could plug in different parts and get some idea of what I will need to reach my goal?
tarior
If it were me, I'd be racing it stock while building a new motor. Don't forget all the other stuff you're gonna have to change if you end up with a real 400 hp mill. Chassis, gears, axles, traction aids, slicks, etc, etc, etc, etc.
If you wanna learn racin' and such, drop by this joint.
[url]http://amcdragracing.freeforums.org/index.php[/url]
