Dodge RamCharger Central banner
41 - 60 of 95 Posts

·
Registered
Joined
·
2,161 Posts
I didn't want to be the one to mention that 350 horse seems awfully optimistic without tearing down the bottom end.

Unless a guy is going crazy with aftermarket heads, I guess.

I dunno, my coworkers are always telling me I'm a glass half-empty guy :)
THANK YOU! I was just coming here to post this. 350 horsepower from a LA 360 with stock pistons and heads is a very tall order. To achieve that number would mean serious head work and a serious borderline cam. Mopar actions truck torque engine from the 90s was built to the hilt and still only made 320 hp. Their green monster 360 had aluminum heads and all the best 340 stuff and barely made that.
 

·
Registered
Joined
·
508 Posts
THANK YOU! I was just coming here to post this. 350 horsepower from a LA 360 with stock pistons and heads is a very tall order. To achieve that number would mean serious head work and a serious borderline cam. Mopar actions truck torque engine from the 90s was built to the hilt and still only made 320 hp. Their green monster 360 had aluminum heads and all the best 340 stuff and barely made that.
I’ve got a X headed 340 In my Cuda. 9.5:1 pistons and a pretty hot cam. I forget the exact specs off hand it’s been 15 years since I built it. Anyhow, I’d be surprised if it’s making much more than 300.

It’s been my experience, that your typical shade tree small block guy is rarely making more than 300 horse on a street motor. Regardless of make.

Chevy guys are the worst about that. :)
 

·
Registered
'79 Dodge Power Wagon Macho
Joined
·
3,917 Posts
What the heck are you guys talking about?? A bone stock 340 made over 300 hp - more like 330 horse. A mildly warmed up 340 or early 360 can see 350 horse all day long. My 340 in my Duster smoked big block Chevy's many times.

Here is a mostly bone stock 340 on the dyno - guess how much hp it made........

 

·
Registered
Joined
·
508 Posts
An 80s 360 isn’t running the kind of compression that 340s did.

Now I was mostly referring to the local idiots who put a cam in a bone stock 80s Chevy 350, add a 4 barrel and headers and then start making claims about 350 horses. Fat chance of that

Most engines dyno at less than what their owners estimate. So I’ve taken to low ball guesses
 

·
Registered
'79 Dodge Power Wagon Macho
Joined
·
3,917 Posts
Yes, an 80's engine is hard pressed but a 70's LA360 can do it. My buddy dumped a 70's 360 into his '68 Formula S fastback one summer after blowing the 340 in it and swapped his cam and intake and ignition from the 340 to the 360 and that thing was a rocket ship also. We howled at how fast it was.
 

·
Registered
'79 Dodge Power Wagon Macho
Joined
·
3,917 Posts
Also, the Chrysler factory underrated their horsepower numbers intentionally back then. All high performance Mopar's were underrated in horsepower. The 440 HP was known to make close to 480 horse stock and the Hemi's were definitely over 500.
 

·
Registered
Joined
·
63 Posts
Discussion Starter · #48 ·
Yes, an 80's engine is hard pressed but a 70's LA360 can do it. My buddy dumped a 70's 360 into his '68 Formula S fastback one summer after blowing the 340 in it and swapped his cam and intake and ignition from the 340 to the 360 and that thing was a rocket ship also. We howled at how fast it was.
Idk if it matters but my motor is, according to the PO, out of a 90 or a 91 pickup. So the motor itself is a few years newer than the truck.
 

·
Registered
'79 Dodge Power Wagon Macho
Joined
·
3,917 Posts
It does matter. A '90 360 makes an advertised 8.0:1 and with those numbers you can't make much. I never said that it would make 350 hp but you can certainly improve the power over stock with stock pistons and heads but when you do pistons and heads you will certainly see 350 hp numbers and up.
 

·
Registered
Joined
·
508 Posts
Also, the Chrysler factory underrated their horsepower numbers intentionally back then. All high performance Mopar's were underrated in horsepower. The 440 HP was known to make close to 480 horse stock and the Hemi's were definitely over 500.
I thought it was only the most powerful that got underrated? Hemis, 440-6 and the like?

I didnt think they underrated the 340s too.
 

·
Registered
'79 Dodge Power Wagon Macho
Joined
·
3,917 Posts
I thought it was only the most powerful that got underrated? Hemis, 440-6 and the like?

I didnt think they underrated the 340s too.
All of the Rapid Transit cars were underrated. Plymouth's also.
 

·
Registered
'79 Dodge Power Wagon Macho
Joined
·
3,917 Posts
If your 340 feels like it barely has 300hp, then you better find someone to tune that puppy.
 

·
Registered
Joined
·
508 Posts
If your 340 feels like it barely has 300hp, then you better find someone to tune that puppy.
It has plenty of power. I’m just guessing. And I don’t have a whole lot to compare it to.

I just know my experience with what people think they have and what they actually have are almost always different. So maybe I’m just low balling it.
 

·
Registered
'79 Dodge Power Wagon Macho
Joined
·
3,917 Posts
Didn't you watch that video I just posted? There's your evidence right there ; )
I don't have any actual data confirming that but I think it's safe to say that every stock Chrysler engine from the 273 Commando to the Hemi, dyno out at higher numbers from the random articles I've read over the years plus from first hand experience I've had with the 340's, 383's and 440's that I've owned over the years and with other friends dyno numbers. I've never owned a Hemi car but I've been in a few and they pull harder than a 425 horse engine does, that's for sure. My buddy had a 350 horse 350 in his Camaro and my Duster smoked him all the time. It also beat up on the 396 cars also, hahaha.
 

·
Registered
'79 Dodge Power Wagon Macho
Joined
·
3,917 Posts
Idk if it matters but my motor is, according to the PO, out of a 90 or a 91 pickup. So the motor itself is a few years newer than the truck.
If you want to free up some horsepower, you could invest in a good set of roller rockers to go with that roller cam in there.
 

·
Registered
Joined
·
508 Posts
Didn't you watch that video I just posted? There's your evidence right there ; )
I don't have any actual data confirming that but I think it's safe to say that every stock Chrysler engine from the 273 Commando to the Hemi, dyno out at higher numbers from the random articles I've read over the years plus from first hand experience I've had with the 340's, 383's and 440's that I've owned over the years and with other friends dyno numbers. I've never owned a Hemi car but I've been in a few and they pull harder than a 425 horse engine does, that's for sure. My buddy had a 350 horse 350 in his Camaro and my Duster smoked him all the time. It also beat up on the 396 cars also, hahaha.
I skimmed through the video. I meant something from corporate.

I’ve heard and experienced similar things over the years.
 

·
Registered
Joined
·
954 Posts
Start with a magnum 360. The Mopar 300 hp crate 360 was nothing more than a production truck block with a car oil pan, an M dual plane intake and I believe a 750 CFM carb. There was a 380hp version as well that added a different cam and a single plane intake. I have a 91 W350 with a carbd magnum 360 and I can tell you its a night and day difference from the LA 360. Magnum 360, stock with an edlebrock intake, 650 cfm carb, mopar electronic ignition, and stock LA360 manifolds.
 

·
Registered
Joined
·
63 Posts
Discussion Starter · #59 ·
Jesus guys, I wasn't expecting all of this information. I asked for it though, so thanks.

I'm still a total beginner with working on stuff and especially with engines, so this is kind of a lot. As such, let me try to narrow things down a bit. I don't have the tools (or knowledge, for that matter) to do a motor swap, so for now I'm going to rule out a magnum or a big block. They would be nice, but for my purposes I think it'll be far more manageable for me to just modify the engine I already have. To bring everyone up to speed if they haven't read the whole thread, this motor is an early 90s (not sure on the exact year so let's call it a 90) 360, has an Edelbrock 1406 600cfm 4 barrel carb, LD340 intake, headers, and dual exhaust. Everything else is stock. So, the question now is where to go from here. I'm a little confused on compression because the comments are conflicting. Some of you are saying stock is fine, some are saying to go higher. So which is it? And how do you go about increasing compression?

For the record, I most likely won't be tearing into this until next year sometime, so I've got time to think about it. I just wanted to start asking around to get some ideas.
 

·
Registered
Joined
·
954 Posts
You wont make any power without compression, a stock 90 TBI engine probably had about 8:1 or so, you really need to get that number up into the 9s
 
41 - 60 of 95 Posts
Top