Cams for 318's
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Stock longblock 4 bbl headers xe262h 282hp @ 5000 rpm
318 Long Block Bolt Ons - Tech Articles - Mopar Muscle Magazine
I always love the people that say a 273/318/340 isn't big enough from people that have not done one or done one right. I started with a 273 in a 64 Barracuda with a 4 speed. The 273 was pulled and sent out for 10.5 forged pistons and good machine work. Since it had a good forged crank and pistons, I experimented with that 273 over the course of 200,000 miles and 15 to 20 years. It was a daily driver and was built initially for High Performance with stock heads (1.78 intake and 1.50 exhaust valves), Offy intake, Holley 1850 600 cfm vacuum secondary, 284 duration solid cam, factory exhaust manifolds, straight thru Commando single exhaust, and a Mallory double life mechanical distributor. It was fast enough to beat most cars with 100 cu in larger engines. As a matter of fact it had the same power to weight as a late 60's 4 speed Road Runner, yeah I raced him and he knew how to race. Years later the best 273 combination had the same short block with milled .040 72 340 "J" heads (1.88 intake, 1.60 exhaust valves, and 64.8 cc chambers), a used 50,000 mile 72 340 cam, lifters, and shimmed hydraulic rocker arms, 71 340 intake and TQ, and the 72 340 electronic ignition with a Chrome box. With 4.10 gears it would fry the tires through 1st, 2nd, and 1/2 way through 3rd, and do the Quarter just under 100 mph. Rpm dropped 1,000 rpm between shifts. With 2.76 gears it would pull mid 20s mpg cruising on the highway. All with a stock used 268 duration, .430 lift 114 centerline hydraulic flat tappet cam. If I can do it with a 273, why can't you do it with a 318? 340? 360? No strokers, no nitrous, no aluminum heads, no headers, no high dollar ignition, no aluminum radiators. And I still have that 273. Never blew it, even after missed 6,500 rpm power shifts. Need dyno numbers, what a joke, go out and live a little. Put something together and run it. Don't have a drag strip? Go out into the country, mark off a quarter mile and give it a go. Don't measure time, measure mph. Drag racing is a specialized sport, not the same as a street car.
Dyno test of 262 cam from link comments-
Issue 1- They never actually said with the compression ratio was. Is it 9.2:1 (actually very likely real close to that) or 8.8:1 (likely less)?
Issue 2- I sure would have liked to see what the dyno said about adding just the 4 barrel. That would have been more logical than dyno-ing "just the cam".
I can't believe those guys didn't think of that.
Issue 3- I wish they would have also done the "256" cam. Comp's "desktop dyno" shows a MUCH broader torque curve (they did note a broader curve), and only a 10 max HP reduction. That's a VERY logical trade off in a street motor build. It would have been worth it to see it on the dyno, vs "on paper".
Issue 4- I would bet some pretty serious coin that the "performer" intake is WAY more common and much easier to find "cheaper" than the M-1.
Issue 5- Why TF didn't they continue the low RPM readings at 2K? this is a mild build, we want to know (especially if it drops). Street driving doesn't start at 3K.
Interesting note 1- Despite what 99% of FxBO members responded when the question was posed, they elected to use the factory 318 stock cam springs with the 262 cam. EDIT- the footnote says that cam came with lifters, WTF?
Interesting note 2- 190 HP is pretty good for a stock 318. Chrysler said a 73 318 with dual exhaust was good for 170. Must be 20HP from the $1000 headers. (or maybe it's the 9.2:1 engine)
I knew they couldn't resist throwing on something they "just had laying around". Every single one of these write-ups does, usually to the tune of a major effect on the outcome, and potentially adding hundreds of dollars to the "low buck" status for a reader to cough up while also skewing the results away from the intended point of the test.
Issue 1- They never actually said with the compression ratio was. Is it 9.2:1 (actually very likely real close to that) or 8.8:1 (likely less)?
Issue 2- I sure would have liked to see what the dyno said about adding just the 4 barrel. That would have been more logical than dyno-ing "just the cam".
I can't believe those guys didn't think of that.
Issue 3- I wish they would have also done the "256" cam. Comp's "desktop dyno" shows a MUCH broader torque curve (they did note a broader curve), and only a 10 max HP reduction. That's a VERY logical trade off in a street motor build. It would have been worth it to see it on the dyno, vs "on paper".
Issue 4- I would bet some pretty serious coin that the "performer" intake is WAY more common and much easier to find "cheaper" than the M-1.
Issue 5- Why TF didn't they continue the low RPM readings at 2K? this is a mild build, we want to know (especially if it drops). Street driving doesn't start at 3K.
Interesting note 1- Despite what 99% of FxBO members responded when the question was posed, they elected to use the factory 318 stock cam springs with the 262 cam. EDIT- the footnote says that cam came with lifters, WTF?
Interesting note 2- 190 HP is pretty good for a stock 318. Chrysler said a 73 318 with dual exhaust was good for 170. Must be 20HP from the $1000 headers. (or maybe it's the 9.2:1 engine)
I knew they couldn't resist throwing on something they "just had laying around". Every single one of these write-ups does, usually to the tune of a major effect on the outcome, and potentially adding hundreds of dollars to the "low buck" status for a reader to cough up while also skewing the results away from the intended point of the test.
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AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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Did I mention that my 2012 Orlando has a 2.5liter-6 speed advertised at 167 RWHP? 2.5 liters is 152.5 cubes that'd be close to 200 crank HP. Did I mention it pumps 220 psi on the compression tester?
This engine has a VVT system that switches at about 4500 rpm. The only time I might use it is during a misjudged passing maneuver. The car is advertised at over 3600 pounds.
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For a 318 streeter, it's all about the pressure, ............ unless you like a 3000 stall convertor..........
But if you have a clutch, then your engine is nearly married to the tires, so if the rpm comes down too far, you gotta downshift or that same engine better have some pressure.
The 73 up low-compression 318s seldom pump over 135 psi, which is disgustingly low.
I had one in my Barracuda that was my winter engine.
It came out of a 75Dart, in the which it wore the 340 top-end and cam, no headers but dual exhaust. ran a TFII A904, factory stall, and 3.23s. It was a complete and utter dog............ except it had a pretty good passing gear; 60=3800 in Second gear. The car got to be too rusty to be seen in public, so;
I took that engine out, put it back to stock, and dropped it into my Barracuda for the winter, with 2.76s, that same TF-II/904 and a 2800stall. But it now wore the TTI headers and dual 3" full-length exhaust.
What a difference! Nicest 318 I ever had. Still only 135psi.
I liked it so much that in 6 winters I never touched it. I did however every winter run a different trans and gears.
One winter she ran 4.30s with a double overdrive manual trans. 65=1930rpm. I used the GVod as a splitter, and what a hoot that was. Seven useable gears with pretty tight ratios. Ka-blam! What a combo!
The Roadgears were; 13.29-10.36-7.18-5.60-4.30-3.35-2.38 with splits of
.78-.69-.78-.77-.78-.71od..... a gear for every occasion, and another one close by.
This engine has a VVT system that switches at about 4500 rpm. The only time I might use it is during a misjudged passing maneuver. The car is advertised at over 3600 pounds.
-----------------------------------------
For a 318 streeter, it's all about the pressure, ............ unless you like a 3000 stall convertor..........
But if you have a clutch, then your engine is nearly married to the tires, so if the rpm comes down too far, you gotta downshift or that same engine better have some pressure.
The 73 up low-compression 318s seldom pump over 135 psi, which is disgustingly low.
I had one in my Barracuda that was my winter engine.
It came out of a 75Dart, in the which it wore the 340 top-end and cam, no headers but dual exhaust. ran a TFII A904, factory stall, and 3.23s. It was a complete and utter dog............ except it had a pretty good passing gear; 60=3800 in Second gear. The car got to be too rusty to be seen in public, so;
I took that engine out, put it back to stock, and dropped it into my Barracuda for the winter, with 2.76s, that same TF-II/904 and a 2800stall. But it now wore the TTI headers and dual 3" full-length exhaust.
What a difference! Nicest 318 I ever had. Still only 135psi.
I liked it so much that in 6 winters I never touched it. I did however every winter run a different trans and gears.
One winter she ran 4.30s with a double overdrive manual trans. 65=1930rpm. I used the GVod as a splitter, and what a hoot that was. Seven useable gears with pretty tight ratios. Ka-blam! What a combo!
The Roadgears were; 13.29-10.36-7.18-5.60-4.30-3.35-2.38 with splits of
.78-.69-.78-.77-.78-.71od..... a gear for every occasion, and another one close by.
They said it was a jobber rebuild be low cr
I'd guess 20-30hp but would of been nice, probably didn't cause of time and or laziness
Would be nice if people did a little more testing with different mild 318 combos, this all we got that I know of.
But really even with mild engines at full throttle do you spend much time under 3000 k
These dyno test aren't representing street driving conditions anyways.
What would that be? their basically throwing an engine in their buddies truck but used the opportunity to give us a basic Idea what such mods could do.
Problem is most people doing a 318 is that generally it's what's in the car and running and just want to add 4bbl and mild cam , not rebuild for cr not install gears or stall, probably looking to burn a little rubber. 318willrun's 318 didn't do to bad with these basic mods. What may be a dog to you might be fine to others.
Dan the man
Well-Known Member
The chevelle should've been faster than that. Maybe he didn't know how to tune his combo. My stock 74 duster with a /6 ran low 17's. Depends on what else was done, that 850 could've been to much carburetor, I've seen it before
Dan the man
Well-Known Member
Chevy 235 which was in the vette, I find it hard to believe that gm would back down from the mopar 170 slant 6. The/6's can't be spun very tight due to their long stroke/ long rod design and the crankshaft only being supported by 4 main bearings
You need more experience and less theoretical BS and marketing. There was a 170 cu in limit and I was talking about historical fact, the other manufacturers were not even close. All /6 use the same bore, only the rods and cranks change until the smog era. A 170 has the shortest stroke and a shorter deck, and will rev the best of the /6's. Also being the smallest cu in using the same head will naturally rev higher. The 170 I put together would easily beat a Chevy 235 straight six in anything an engine does for next to no money.
Yes, the Holley 850 was too big and the combination was bad. The original QJ was much better, but all the racers ran an 850 double pumper. That is the point I was trying to make. One of the guys had a 4 cylinder Honda that was almost as fast.
Dan the man
Well-Known Member
Wow, that's awesome
Dartswinger70
Well-Known Member
There was a feller I knew that had a Super six in a valiant hed always say how it could lay rubber up and down the street...he tried it once I dont remember it being spectacular but it did do a burnout.
Dan the man
Well-Known Member
I had 3 /6's, I wasn't impressed by the acceleration of any of them, actually all of them were dogs. I didn't have a lot of money to invest in them and I pretty much thought that it would be a waste of time and money. I had a 1972 gremlin x with a 258, now there's a car that ran great for being stock. Those/6's didn't have a chance against it not from a dead stop or a 30 mph punch.
Great article, like how they broke down the steps of the add ons.
Was wondering about the compression ratio of their Recon 318 long block? Something like 8.2 to 8.5:1 compression ratio?
Guessing by the looks of the original 318 truck exhaust manifold, that engine probably came out of a 1976 D100 Pickup with the same compression ratios listed above.
Was wondering what the final Results would have been had they started with a 1969 318 9.2:1 230 horsepower stock 2 bbl engine.
Stock 230 hp, with the addition of the cam, 4 bbl intake and 4 bbl carb an upgrade of 100 horsepower.
Puts them at:
230 + 100 = 330 horsepower
Hmmm . . . Interesting Thought.
Something like that
1 cr point suppose to gain 3-4% hp so like 290 hp
High doubt the 318 ever actually made 230 hp, look at the gross 2bbl 189 hp number before cam and 4bbl, not much difference between 318 specs over the years, 230 hp very generous rating.
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330 hp nope
i had the setup you speak of 69 318 340 cam factory 340 intake carb headers 3.23s
raced a very quick stock 69 340 aut fb cuda 727 4.10s he ran 13.8 13.9 he beat me 5 cars evertime
later
340 heads
spray
purpleshaft cam
4.56 gears
i smoked him by alot
too much gear 4.30s would have good
Dan the man
Well-Known Member
I don't know what class you're talking about,but I looked up what car manufacturers made a 170 CID 6 cylinder engines and I only found 2, one was the mopar 170 and a ford. GM and AMC never offered a 170 cid engine. I'm sure that there was more than 2 manufacturers involved in the event. Do you know what manufacturers were involved in the competition
I don't believe reman long blocks come with exhaust manifolds, so you can't use that as evidence.
IMO compression ratio should have been furnished by the reman company. A look at the casting date could help, but you can't guarantee what parts were used in the reman process.
I also don't buy 230 HP for a stock 318. (EDIT- until the 5.2 Magnum)
I'd also suggest that an 80's roller 318 rated at 9.2:1 is actually very close to that number, whereas the early 9.2:1 engines may fall into that category of "significantly less"- based on evidence of other engines of that vintage actual measured ratio.
I also made an error when I said 190 hp was good in the test.
Dyno is gross HP and the factory 150/170 numbers are net.
IMO compression ratio should have been furnished by the reman company. A look at the casting date could help, but you can't guarantee what parts were used in the reman process.
I also don't buy 230 HP for a stock 318. (EDIT- until the 5.2 Magnum)
I'd also suggest that an 80's roller 318 rated at 9.2:1 is actually very close to that number, whereas the early 9.2:1 engines may fall into that category of "significantly less"- based on evidence of other engines of that vintage actual measured ratio.
I also made an error when I said 190 hp was good in the test.
Dyno is gross HP and the factory 150/170 numbers are net.
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Enjoy! First 7 out of 7.
Automotive History: When The New 1960 Compacts Went Racing - The 130 MPH Valiants Cream The Corvairs And Falcons - Curbside Classic
(first posted 1/17/2012) The arrival of the new compacts by the Big Three in 1960 was the beginning of a major new era. The race for sales also turned […]
Those interested in actual 318 testing and development should bookmark @CPDave's posts.
When he bought the Dart from Josh, it had a Dick Ott built 318 with a 262 adv duration, 420/420 lift cam.
My experience was that it had a very responsive throttle.
The reason for developing the 318 was that he (Dave) was able to get it into the SVRA rules. (Otherwise he'd have to use an engine under 305")
Anyway. here's the post that outlines the development.
www.forabodiesonly.com
and one just on the current build
www.forabodiesonly.com
When he bought the Dart from Josh, it had a Dick Ott built 318 with a 262 adv duration, 420/420 lift cam.
My experience was that it had a very responsive throttle.
The reason for developing the 318 was that he (Dave) was able to get it into the SVRA rules. (Otherwise he'd have to use an engine under 305")
Anyway. here's the post that outlines the development.
302 heads
lelo, that was my next question, if i port the heads i have based on the head porting sticky on here and have them milled slightly that should be a big help theyre supposed to be 60-62 cc's am i correct in this thinking. and does anyone other than kb make a higher compression piston for the 318?
www.forabodiesonly.com
and one just on the current build
I've seen A LOT of posts about making HP with a 318-So why is it so ???
There is a stock 318 long block low cr build that made 282hp @ 5000 rpm with 4bbl and headers and a xe262 cam, add some cr and bigger cam can't see why you can't get 300 hp out of stock heads, but if your buying pistons for cr might as well go to with better heads. Doesn’t that defeat the “Cheap...
www.forabodiesonly.com
It is very difficult to get stable low rpm WOT readings on a dyno. I've not run an engine dyno, but even with a stick getting full load WOT on a chassis dyno has to start at the lowest rpm you can get it into third.
Engine dynos are a little different as they are set up with given rates of accelation. When we see two different engine dyno results, one question to ask is whether they both used the same rate of acceleration.
I agree it would be nice to see the rpms lower but the dyno was not a great tool for that. It was interesting that when Hot Rod tested the 340, it looked like some streetable power (under 3500 rpm) was lost when going to the LD4B dual plane. Of course on the street we're mostly wanting good part throttle, throttle response, and that's another thing that's hard to test for on a dyno...
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