AJ/FormS
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- Apr 26, 2016
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It is really hard to argue against 42 cubic inches, especially for a streeter. If I was swapping engines,looking for a lil performance, the 318/5.2 would not be on my list,period.
If I was somehow limited to a 318LA, the very first thing I would do is increase the compression ratio. No matter how broke I was, I would sooner do that and bolt the 2bbl back on.
But before I would do anything; you know, gears and stall.
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Wait; remember the first gen 318 LAs back in the sixtys. Those were 9.5Scr rated and 230 crank HP. With the 240* cam, the 2bbl, log manifolds and single exhaust. What was that in Net? There was no Net for that engine, so you gotta guess. And I guess 190 net. Compared to 230 of the 5.2Ms. That's 40 hp.
Where does that come from? Well; The 5.2 cam is
250/264/110+19 and the 318LA was
240/248/112+2
So some of the power is in the cam and bigger TB, on account of the operating rpm was increased about 300rpm, so that accounts for perhaps 15 to 20HP. So that leaves 20 to go. I'll guess the rest is in the heads.
Now recall the smoggerteen with its 150hp rating...... Still the 240* cam, still a 2bbl, same single exhaust. So where did the estimated 190 less 150 =40 hp go?
I'll guess some was in the lower 8.0Scr rating, some was in the lazy timing, and the rest was in the new rating system. How much to give to each? IDK. I'll guess 10 to 15 in the compression and 8 to 10 in the timing, leaving about 15 to 20 in the paperwork.
The point is this; bolt-on for bolt-on, the un-opened smoggerteen has an 80hp deficit to the 5.2M. It's in the Scr, the cam, the heads, and the rating system.
At 230, the M is .72 hp per cube.
At 150, the smoggerteen is .47 hp per cube.
To get to 230, at .47 hp per cube, you would need 230/.47= 489 cubes ; that's how lazy the smogger teen is.
Ok but say you installed your bolt-ons onto a good smoggerteen and she output 200hp, so now .63 hp per cube. To get to 230 with .63, you would need 230/.63=366 cubes.
I know you keep saying you don't need a tire frier, but you also keep throwing in 4bbl, headers, and now alloy heads. Look; you can dress up a pig to go to church, but it's still just a pig.
But your bolt-ons, onto a 5.2M at say 270hp net with a "baby cam" is .85 hp per cube and a pretty good engine....... but still not a tire frier with 2.2/2.45 gears and a factory stall TC.
Sure you can build a 318LA up to that 270 hp but if you want to keep some bottom end, yur gonna have to up the Scr. And yes alloy heads will make more power than your smogger heads, but again, it will require even more Scr to make it happen.
Whereas the Magnum already has the perfect Scr ratio for the retimed to straight-up factory cam, saving you the cost of ; heads, pistons, a "baby cam", etc, Which money you can now spend on getting the M installed and running, with money left for a high-stall, and maybe a downpayment on a proper rear end.
If you find a nice 5.9 for similar money, then you will have the best of both worlds, with enough torque to possibly use the stock TC.
It seems to me no matter how you slice this, something has to be un-installed. Either the trans comes down for a TC swap, or the engine comes out , or both.
Alloy heads onto the 8.0 318LA-engine with a "baby cam", and no other changes is gonna be a great-big disappointment. If you go this route do some time trials, both before and after. Else you are gonna be fooling yourself as to how much improvement you think you got.
Post 17 is right on the money; as are many others
and almost the common thread is; with those hiway gears, the stockScr LA is a sad deal; and if you buy a used Magnum, then bigger is better.
But some of us agree, that if you free up the LA teener with a TC and gears, then just bolt your stuff on and go.
and I say if you don't increase the Scr of your 318LA, then leave the factory cam in it; that is to say, if you do baby-cam it, then make sure the Ica is the same 50*or smaller.
If I was somehow limited to a 318LA, the very first thing I would do is increase the compression ratio. No matter how broke I was, I would sooner do that and bolt the 2bbl back on.
But before I would do anything; you know, gears and stall.
xxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxx
Wait; remember the first gen 318 LAs back in the sixtys. Those were 9.5Scr rated and 230 crank HP. With the 240* cam, the 2bbl, log manifolds and single exhaust. What was that in Net? There was no Net for that engine, so you gotta guess. And I guess 190 net. Compared to 230 of the 5.2Ms. That's 40 hp.
Where does that come from? Well; The 5.2 cam is
250/264/110+19 and the 318LA was
240/248/112+2
So some of the power is in the cam and bigger TB, on account of the operating rpm was increased about 300rpm, so that accounts for perhaps 15 to 20HP. So that leaves 20 to go. I'll guess the rest is in the heads.
Now recall the smoggerteen with its 150hp rating...... Still the 240* cam, still a 2bbl, same single exhaust. So where did the estimated 190 less 150 =40 hp go?
I'll guess some was in the lower 8.0Scr rating, some was in the lazy timing, and the rest was in the new rating system. How much to give to each? IDK. I'll guess 10 to 15 in the compression and 8 to 10 in the timing, leaving about 15 to 20 in the paperwork.
The point is this; bolt-on for bolt-on, the un-opened smoggerteen has an 80hp deficit to the 5.2M. It's in the Scr, the cam, the heads, and the rating system.
At 230, the M is .72 hp per cube.
At 150, the smoggerteen is .47 hp per cube.
To get to 230, at .47 hp per cube, you would need 230/.47= 489 cubes ; that's how lazy the smogger teen is.
Ok but say you installed your bolt-ons onto a good smoggerteen and she output 200hp, so now .63 hp per cube. To get to 230 with .63, you would need 230/.63=366 cubes.
I know you keep saying you don't need a tire frier, but you also keep throwing in 4bbl, headers, and now alloy heads. Look; you can dress up a pig to go to church, but it's still just a pig.
But your bolt-ons, onto a 5.2M at say 270hp net with a "baby cam" is .85 hp per cube and a pretty good engine....... but still not a tire frier with 2.2/2.45 gears and a factory stall TC.
Sure you can build a 318LA up to that 270 hp but if you want to keep some bottom end, yur gonna have to up the Scr. And yes alloy heads will make more power than your smogger heads, but again, it will require even more Scr to make it happen.
Whereas the Magnum already has the perfect Scr ratio for the retimed to straight-up factory cam, saving you the cost of ; heads, pistons, a "baby cam", etc, Which money you can now spend on getting the M installed and running, with money left for a high-stall, and maybe a downpayment on a proper rear end.
If you find a nice 5.9 for similar money, then you will have the best of both worlds, with enough torque to possibly use the stock TC.
It seems to me no matter how you slice this, something has to be un-installed. Either the trans comes down for a TC swap, or the engine comes out , or both.
Alloy heads onto the 8.0 318LA-engine with a "baby cam", and no other changes is gonna be a great-big disappointment. If you go this route do some time trials, both before and after. Else you are gonna be fooling yourself as to how much improvement you think you got.
Post 17 is right on the money; as are many others
and almost the common thread is; with those hiway gears, the stockScr LA is a sad deal; and if you buy a used Magnum, then bigger is better.
But some of us agree, that if you free up the LA teener with a TC and gears, then just bolt your stuff on and go.
and I say if you don't increase the Scr of your 318LA, then leave the factory cam in it; that is to say, if you do baby-cam it, then make sure the Ica is the same 50*or smaller.
