hang on fellas;
the OP clearly stated that he wanted a 340,
found them too pricey;
but is willing to break the bank for a 300hp 318.
I was responding to the issue from;
the cost of things,
the ease of assembly, and
the fact that a hi-compression 360 can totally waste a lo-compression 318 as to hiway economy,
and still make plenty of power, easily eclipsing 300hp.. using all stock major components; and in the process, the 360 makes enough torque to annihilate the tires.
The OP is in no hurry, and is exploring his options, already moving in the direction that will cost big money, for, in a 318, very little gain; surely a recipe for disappointment........
I am merely presenting a logical argument to the OP, for a bigger SBM, based on less money having to be spent, as, the OP has already stated wanting a bigger engine; and, of the SBMs, the 360 is the best place to stick his 318Whiplash cam (*2) into, which already has large-port heads, and adequate valve sizes to work with that cam. The additional 42 cubes will nicely replace the bottom-end torque, that the Whiplash sacrificed in the stock lo-C 318; and so, OP can re-use the stock convertor and 3.55s, albeit with a SureGrip required. OP already has all the add-ons to make the 360 with the 318 Whiplash, a great combo!
If it ends up too powerful for the chassis, and it will, well isn't that just too bad.....lol.
(*1) the 318whiplash, in a 360, with big-port heads and AG will want a shift rpm of more than 5000, and you can wring it out to 5500 all day, with the right valvesprings. Speaking of rpm, the 360 under my hood, with KB 107s, has been spinning to 7000Plus, since 1999.
(*2) Hughes says that the 318Whiplash (213/226/109+5)( and lifts of .480/
[email protected]), works great in a 318, at "up to"
8.6Scr . OK, but there was no smoggerteen that was ever built to 8.6, so shame on Hughes for making you guess if it will work well in your STOCK lo-C teener. IMO Hughes is a lil slippery when it comes to camshaft specs.
Ima guessing your cranking pressure, in your sub 8.0Scr 1973 smoggerteen, is around maybe 145, so while it might be true that this cam works with 8.6, 145psi is about what a stock teener would put out in Indio. Read, lo-rpm pussyfied. OOps I mean soft.
The 360,will accept a lil more Scr; maybe something like 9.4/1, which is an easy build for a 360 with stock iron heads, and KB107s. That Whiplash cam has enough extraction duration, and a small enough overlap period, that it has the potential, at the right Scr, to make pretty good hiway gas-mileage. I mean, as to extraction and overlap, it's nearly identical to that of the 223/230/110Hughes, the one I used , to make 32mpgUSg. If anything, it's a lil better. You will, of course, not get close to that with 3.55s, geared 65=2900@ zero-slip, perhaps 3000 or more, on the tach; I was geared 85=2100 using a manual trans and overdrive.
(3) BTW, Biden has already stated that he is gonna raise the price of gas exponentially. So being able to run 87 gas
and getting great fuel mileage, IMO, is sorta crucial to actually being able to drive the car, in the coming years. Biden and/or his party, is/are never gonna get voted out; they are here to stay. In the very near future, he is hoping to rid America of people, never mind gas-burning cars. In this scenario, a small cam 360 makes the most sense....
to me anyway.
I can't speak for the rest of you big-balled 300hp, 318 boosters.
In case you have forgotten,
here is a recap of some of the things that OP has said;
To be clear; I am not a 318 hater,
having had many many of them, in my 52plus years of driving. Almost all of our DDs have been 318cars. We have almost always been a two or three car family; one 318 car for me, a slanty-car for the wife, and a 340 or 360 bruiser for me to take out my frustrations on. With the occasional "other" car hanging around.
Btw
I would rather have a 340 shortblock with a 318 top and cam, than a 318 short with a 340 top and cam. It's really really hard to say no to the low-rpm torque increase.
As a streeter, yur only gonna pass thru the power peak once at WOT, possibly twice, and the first time don't count cuz the tires are melting. With 3.55s, the second time comes at around 65/70 mph........... Whereas the rest of the time, the engine will be lumbering along at 3000rpm or less..... probably closer to 2000, so.......... I mean, what good is 300hp at 5000, if the engine is sucked-out at 2000.............. On the street, you have a choice; 1) build the engine to have some honest torque, or 2) yur gonna need a hi-stall and near 4.xx series gears, AND an overdrive. I've done it both ways.
At 3600 pounds, I prefer a 360. That would be 10 pounds per cubic inch, a number hard to find fault with. My 1970 Swinger340 back in 1970, was 9.79 with me in it. It was slow; posting 98 in the qtr, versus 93 in the Eighth, for my Barracuda........
My 367 is nothing special, being built nearly the same as that 1970 340. The Scr is a true 10.95 compared to an advertised 10.5 for the 340. My cam is a 230/237/110 compared to the 340 being 228/236/114. Both were 4-speeds, had 4bbls, but my 367 has headers and full-length 3" duals. Yeah my 367 has OOTB Eddies on it so what.
The car posted that 93mph@3467 pounds, being shifted at 7000, well past the powerpeak of around 5100,lol. All in all, the advantage is just the headers, the free-flowing exhaust, and the 27 cubes. And the Barracuda was even a lil heavier than the Swinger.
They say that the 1970 340 made a tic over 300hp with headers and a good tune-up. Do you really wanna put that gas-hog 340 cam into your 318? And bump it's compression to 10.5, and make maybe 280hp; when the 360 in the same trim might make 320hp? In terms of dollars, is the cost of the 360 core worth 40 hp? Or a 5.9M? or even a 5.2M
Nah, "I like my 318", is the mantra.
Ok fine, there can be no argument against liking your 318. You like what you like, I get that. I don't like short,fat,black-haired girls. That doesn't make me a hater of short,fat,black-haired girls. If a short, fat, black-haired girl was the last girl on Earth, I would love her 17 children's worth. At least.
People throw the word "hate" out on everything, sorta like they brandish "racism".