Magnum 5.2l vs 360 LA?

[mygasser]

So, to be clear, in your mind you choose gear and tire size and then match the cam? Kind of like choosing tire size and rims before narrowing a diff? This may seem obvious .....but I like to get a good game plan and stick with it to eliminate extra costs doing things twice.

thanks rumble fish!

it's easier to buy the wheels and tyres you really want and narrow the axle to suit, rather than have to compromise on the wheels you want due to fixed axle width. after all you can't see the axle, the wheels/tyres are almost the first thing you see so need to be right. axle width and rear gear can then be calculated to suit not only the engine but tyre size too.

 

[mygasser]

I know when I narrow and gear diffs, I choose tires and wheels first, then mold the car around those choices.

[/QUOTE]
yep, just what i usually do.

 

[318willrun]

does the roller la 360 come with 308 heads, as this comparison says stock longblock.

yes

 

[mygasser]

yes

you're golden then

 

[Bighead440]

Of course withy a piston change and head upgrades, the 360 will always win, but out of the box a 318 Magnum would be hard to beat. That's if you ran identical ignitions, both engines with Air Gap dual plane manifolds and identical carbs. The 318 Magnum would have the roller cam advantage built in, if cam swaps were in the plan (albeit the later 5.9 TBI LAs had rollers). I personally have run 8.20s/8.30s @86mph in the 1/8mi with a stock bore 318 Magnum with unported heads, in a '68 Dart. The motor had the M1 single plane (no Air Gap or China intakes yet, this was in the late '90s) and a way tight 11" oem 727 converter which killed it off the line, a 270HR Comp Cam (custom grind back then) with 218/224*@.050" around .520/.540" lift and headers. No real blueprinting, just a freshened up Jeep GrCherokee motor. You'd be hard pressed to do that with a smogger 360 with just bolt ons, IMO.

 

[273]

just like with ls' then

I also would to find a decent 273 bottom end and add the 380hp crate top end and see what she does.

So basically I want to do a 380hp crate version of 5.9l vs 5.2l vs 4.5l lol

 

[rumblefish360]

 

[AJ/FormS]

NET Figures.
hard to fault that torque curve below 3200;
but I suspect that this is with the keg EFI intake. You won't get that spike with a carburated set-up. And as you can see, it rolls off pretty rapidly afterwards.
But put a 2800/3000TC on it,and match the rear gear to your streeter combo, with respect to that early rpm limit, and yur ready to fly.
Not my cup-o-tea, but it ran really well in my 92 Dakota with 3.91s and the overdrive trans.
Don't let the display size manipulation fool you. By shrinking the horizontal axis, it makes the power curve look disproportionately fast and high. To make it feel like it looks, yur car would need to be half as heavy as it is... or something, lol.

 

[273]

NET Figures.
hard to fault that torque curve below 3200;
but I suspect that this is with the keg EFI intake. You won't get that spike with a carburated set-up. And as you can see, it rolls off pretty rapidly afterwards.
But put a 2800/3000TC on it,and match the rear gear to your streeter combo, with respect to that early rpm limit, and yur ready to fly.
Not my cup-o-tea, but it ran really well in my 92 Dakota with 3.91s and the overdrive trans.
Don't let the display size manipulation fool you. By shrinking the horizontal axis, it makes the power curve look disproportionately fast and high. To make it feel like it looks, yur car would need to be half as heavy as it is... or something, lol.
View attachment 1715778292

A small roller cam would probably add a lot of top end without sacrificing much or none down low. Something like the one I bought for my 5.9l 210/220 .512/.512 112.

 

[rumblefish360]

A small roller cam would probably add a lot of top end without sacrificing much or none down low. Something like the one I bought for my 5.9l 210/220 .512/.512 112.

I was looking at a cam like that. How do you like it and what engine is it in again?

 

[273]

I was looking at a cam like that. How do you like it and what engine is it in again?

Haven't installed it yet, bought the crosswind airgap to go with it, replacing my 5.9l crate engine cam and intake for more low speed power. It's got all the lift of the crate cam minus 20 degree of duration and on 112 instead of 108, Comp says works from 900-5200 rpm sounds perfect for me don't care if i lose 20-40 hp off the top end should still make 360-380 hp, the 5.9l crate dynos 409 hp.

 

[AJ/FormS]

should still make 360-380 hp, the 5.9l crate dynos 409 hp.

every one?

 

[rumblefish360]

Haven't installed it yet, bought the crosswind airgap to go with it, replacing my 5.9l crate engine cam and intake for more low speed power. It's got all the lift of the crate cam minus 20 degree of duration and on 112 instead of 108, Comp says works from 900-5200 rpm sounds perfect for me don't care if i lose 20-40 hp off the top end should still make 360-380 hp, the 5.9l crate dynos 409 hp.

The RPM range works for me pretty much.
I haven’t thought much about it, just a quick browsing of cams. Down the line I’d like to install an overdrive in my ‘79 Magnum. It has 3.55’s on 245/60/15’s now. It used to have 2.76’s. Did well on the Hwy. A very nice cruiser traveling the eastern seaboard.

 

[273]

every one?

Yes if you mean add that cam 4bbl and headers will make 360-380hp to 5.9l and probably 20 ish less hp in a 5.2l.

Here's a 380hp crate and a 300hp crate which has stock cam I think my new cam is halfway in between the two.