Sixpack on a 318 engine ?
- Thread starter roaddevil
- Start date
-
You got a really good price on it, since the intake is no longer available.
Back when mopar did the last 6pack repop for restoration parts I thought the price was stupid, I can’t exactly remember what what it was, but I thought it was way too much. Oh boy was I wrong, I should have bought a dozen of them.
If I could go back 35 years I'd buy and invest in a lot of things that are worth a fortune today, I remember when I could of bought a fully restored T/A Challenger for $25,000 and thought it was crazy money and $50,000 Hemi cars.
At one time I had just sitting around sets for a 440, 383 & 340.
Now all I have is a new intake I bought for a 440, and a Mr. Norms air cleaner.
Heck yeah put it on there. Why not? It'll need more than a "basic re-ring" because it'll need some compression and some cylinder head flow, but you can certainly make it work.
Its always hit or miss on old cars.
Around 5 years ago the WV Hemi baracuda was for sale, in race ready condition, with 5 spare hemi engines in parts for 80K. It was a real SS Hemi car.
ragtopfury
Well-Known Member
Speaking from experience here..... I put a 6 pack set up on the 318 in the 69 Fury ragtop that I had for 17 years. All stock original long block, except I put a 68 340 cam in it. Stock convertor and 3.55 gears. That land yacht would still pull 18mpg if I kept my foot out of it.. not a rocket off the line, but top end out the yingyang.
A 2 barrel until you need it.
ragtopfury
Well-Known Member
Exactly..... or til you want it.....lol
Question for the group. Are the small block center carbs 350 cfm or 500? Just curious
33IMP
Well-Known Member
Nothing.
33IMP
Well-Known Member
All the center carbs are "350 cfm" . Actually, if rated as if they were four barrels, total flow is less than 1000 cfm, in spite of the "1350" b.s.
I believe the corvette 427 tripower carbs are smaller than the Mopar version.
But, thank the vette guys.... if there weren't corvette tripowers, there would be no sixpacks.
Last edited:
33IMP
Well-Known Member
To tho o.p.
If the setup is in great shape, It'll work fine on a 318. Gives you a chance to TELL em it's a 340.
As for performance..... it'll be 95% eyewash on a 318
If the setup is in great shape, It'll work fine on a 318. Gives you a chance to TELL em it's a 340.
As for performance..... it'll be 95% eyewash on a 318
33IMP
Well-Known Member
My opinion only:
A few cubes difference between a Ford 302, Mopar 318, and a 327 chevy, doesn't mean much. The difference is, there were real performance versions of 289/302 Fords, and REAL performance versions of the 327. That is not true of the 318, and it's reputation suffers.
Put equivalent hi performance parts comparable to the 365/375hp versions of the 327, you should get comparable results. Trouble is.... Mopar never did.
A few cubes difference between a Ford 302, Mopar 318, and a 327 chevy, doesn't mean much. The difference is, there were real performance versions of 289/302 Fords, and REAL performance versions of the 327. That is not true of the 318, and it's reputation suffers.
Put equivalent hi performance parts comparable to the 365/375hp versions of the 327, you should get comparable results. Trouble is.... Mopar never did.
The 365/375 horse 327 had a cam in this range. Speed Pro still sells it. Put it in your 318 along with a nice intake and carb and some headers and see where you go. I bet that 327 had 10/1 compression at least which the 318 lacked. A 300° cam is pretty nasty especially in a small cube engine.
Speed Pro # CS118R 254°@ .050 295° adverttised duration
.485 lift 114° Lobe separation.
The Chevy guys say it comes on strong at 3500 to redline. (no idea what that is but guessing 5500+)
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
- Joined
- Jan 19, 2014
- Messages
- 25,866
- Reaction score
- 13,175
As for camming it,
this will depend a lot on the rest of the combo, and specifically on the compression ratio/ cylinder pressure, but includes things like the convertor, tites, and, rear gears
.
If you are running an 8/1 engine, with an 039 gasket, yur already down under 8/1.
With the factory cam, that has an Ica around 48degrees, and at 900ft elevation, your cylinder pressure is already likely to be down around 130 psi, which is darn low.. ANY cam you install, with a later-closing intake, will only make this situation worse; the factory-stall convertor might/would have to go, as would any gears less than about 3.73/ maybe 3.55s in the early A; with bigger cams requiring more stall and ever higher gears.
But
If you are running a 9/1 engine with an 028 gasket, and the small closed chamber heads; well then, your pressure jumps up close to ~160, at the same 48* Ica. Now you have a lil room for a bigger cam. Two sizes bigger, going to an Ica of 55*, will get you down to ~150psi, about as low as I'd dare go.
Yes, at this pressure, you can run the stock convertor with probably any gear; but since the engine is out, I'd put a 2800TC in the 904, and run at least 3.23s. As for me, I'd leave the factory cam in there, and install some closed chamber 1.92 valve heads.
OPINIONS
>Notta chance would I install a cam with a later-closing intake, in an 8/1 318, and
>if you install 360 heads on that 8/1, with 340 cam, Well, the bottom-end is gonna feel like a slanty; Couple that with a factory convertor that is now down to stalling at 1700 rpm, and with 2.76 gears; pos
Been there done that, NEVER gonna do it again, I was such a DA.
>As for the 6-pac, sure, run it, after you get it tuned, it will be fine.
> if you make changes, always pay attention to the Quench.
> I'd put headers on any cam with more than ~30 degrees of overlap, unless the pressure is in the basement......
Newbomb Turk
Well-Known Member
Right. And anything performance that wasn’t on a 318 already can be bolted on or the engine machined to correct it.
33IMP
Well-Known Member
If I remember right, the 365 solid lifter 2.02 head motor had 11 or 11 1/4 to one.
Put a modern solid cam in, some econo w2s on it, 10 to 1 pistons, airgap intake with a 750 dp, headers in/on your 318, and hang on. 400+hp to thrash 327s (and 350s) with.
Edit: the solid cam 327s redlined at 6500, would go past that. I spun my hydro cammed 350 (370hp version) to 7500, cause it would.
It would have been quite a bit faster if I had shifted at 6500. DOH!
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
- Joined
- Jan 19, 2014
- Messages
- 25,866
- Reaction score
- 13,175
I totally get that; my 360 was singing a lovely tune at 7200, with a 270 cam. I only shifted at 7200 because I was ascared to go higher, lol; the engine was willing.,
If you look at these 3 Chev engine built pretty much to the same spec except the 350 has a hydraulic cam, They are making about 355 hp but at different rpms, 302 @ 6600 rpms, 327 @ 6100 rpms and 350 @ 5400 rpms, first thing most are gonna say is yes they make same hp but look at the torque difference, but you shouldn't be gearing these 3 engines similar obviously the 302 is gonna need the deepest set of gears 327 a little less and 350 less than that. So at any given mph the 327 and 302 will/should be turning a higher rpm putting it in it's powerband and should be putting similar hp and torque to the ground.
For most obviously the 350 would be considered the most streetable followed by the 327 then 302, which is a personal choice but for full throttle performance if geared and stalled right should have similar capability.
For most obviously the 350 would be considered the most streetable followed by the 327 then 302, which is a personal choice but for full throttle performance if geared and stalled right should have similar capability.
That right there is a killer deal my friend.
Dale Davies
Well-Known Member
Need a 340 cam or a tich more. Port the heads and use inexpensive LS 5.3 valves. 1.9"/1.55". You do need to install either the LS powdered metal guides or bronze guides, with the 8mm diameter. That also opens the door for beehive springs, retainers and locks.
Go for it, only 22 CID difference. Just need the port flow and velocities.
I believe Magnums had 8mm valves. I do like the idea of beehive springs.
-
