I've seen A LOT of posts about making HP with a 318-So why is it so ???
- Thread starter RAMM
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I agree about CR but a lot of people are dealing with stock long blocks, so cr is what it is or they want an engine that they can drop in and set and forget so for them 8-9:1 is gonna be where it's at and a few 10ths of a cr ain't gonna make much difference as other mods. For those that want to play with tune etc.. then crank up your cr.
yellow rose
Overnight Sensation
I don’t know how they screwed that up, but I watched a right out of the car 426 make about 430 before tuning and when the dyno guy was done, it was 500 HP. It was bone stock. I forget the name of guy who had the dyno and tuned it, but he was a sharp cat. The guy who owned the engine was a friend of my dads, and he asked my dad to go to the dyno with him. I got to tag along. It was late 1970.
To take a 426 and get 425 HP out of it is pretty sad.
It seems that around 9:1 is the point where things start happening.
ir3333
Well-Known Member
To take a 426 and get 425 HP out of it is pretty sad.[/QUOTE]
no no...425hp at 5000 rpm like the factory rating.
It was at 465hp at 6200 and still climbing but the owner said stop right there!
no no...425hp at 5000 rpm like the factory rating.
It was at 465hp at 6200 and still climbing but the owner said stop right there!
SLOPAR72
Well-Known Member
So here is another factor. We all agree and know a properly maintained 318 is mostly run into the ground. So if any of us were to break out the ol' Dialbore gauge on 10 or so 318's how many of them would even be in spec for a rering? And there in lies another problem. If you have to go through the rebuild process then why not just go for a 360? Same work just about and ahead of the game.
At the end of the day it's still 318 CI of a vacuum pump. In a perfect world for me I would love to actually put together a bone stock 318 in good running condition and do minimal upgrades to the motor and put some boost in it. I suspect 1.4 hp per CI can easily be obtained. But it will still come at a price tag.....
It's a good thread and worthy of discussion....
JW
PRH
Well-Known Member
At that time, I really didn’t have much porting experience at all.
The shop I worked at had a guy in town who did most of our head porting.
When I showed him the heads I was going to use, he pointed out a few areas to address...... you know...... do this here, do that there, etc.
I can’t remember if he flowed them for me when I was done with the porting or not, but for some reason I keep thinking the heads flowed 179cfm.
I bought my first flow bench in early 93, and I was messing with 318 heads a bit back then.
That was a small bench, and you tested at 10”, and converted that to 28”.
I remember 318 heads flowed a bit less than “100” at 10”......so, 160’s@28”.
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It boils down to my earlier comment. Some people "just like what they like".
SLOPAR72
Well-Known Member
Yep. You know as well as anybody the 318 is a runner lol.... Did any of them end up with beefier blocks and such through the years?
JW
I believe so. I think I've seen some threads on this forum discussing that.
For all the people saying "340/360", if cubic inches are all that matter, why don't you throw out those boat anchors and get a 440?
Then there are some here complaining that pistons cost $200 more.....if $200 is a deal breaker, this ain't the right hobby....
RRR said it about 3 times..."some people just like what they like"......
I like having a 318 that would surprise people.
Jeff
Then there are some here complaining that pistons cost $200 more.....if $200 is a deal breaker, this ain't the right hobby....
RRR said it about 3 times..."some people just like what they like"......
I like having a 318 that would surprise people.
Jeff
Wyrmrider
Well-Known Member
8 to 1 to 9:1 makes more difference than 9:1 to 10:1
cam needs to match the compression or dynamic compression for .006 seatduration
but 60 over 318 vs 20 over 360
how much difference does the .050 larger bore make on a street motor?.090 or .100 for a 340?
now Magnum blocks seem to be better materiel and easier to get 9.2:1
so if the 318 needs pistons vs a stock 360 magnum no machine work requied for me it's no contest
cam needs to match the compression or dynamic compression for .006 seatduration
but 60 over 318 vs 20 over 360
how much difference does the .050 larger bore make on a street motor?.090 or .100 for a 340?
now Magnum blocks seem to be better materiel and easier to get 9.2:1
so if the 318 needs pistons vs a stock 360 magnum no machine work requied for me it's no contest
yellow rose
Overnight Sensation
no no...425hp at 5000 rpm like the factory rating.
It was at 465hp at 6200 and still climbing but the owner said stop right there![/QUOTE]
I wish I could tell you I know exactly what RPM they test to, but I’m having a hard time remembering if I even had lunch. My guess is it was higher that 6200 but at this point it’s a WAG on my part. At the time I was 7 years old. The HP number always stuck with me, especially after I got to driving age and everybody and their mom had a 500 HP SBC and ive never forgotten that hemi.
And we all know that RPM makes more power. I’d be surprised if they didn’t run it to 7K.
Absolutely I know! I would put a 318 in my 64 Valiant......but man, that's been done and done and done some more. That's why I want to build a mild 451, disguise it as a 64 383 and make it look as factory as possible. When I raise the hood, people will certainly be expecting a small block and they'll ask in surprise "how'd you get "THAT" in there?" It may never happen, because this little 170 runs so good, I'd be committing a sin pulling it out. But, as long as I can do the swap without making permanent changes to the car, I'll likely do it. I'm acquiring all the parts, at least. The driver's side exhaust manifold and steering column and column shift three speed linkage will be the big challenge. If I can keep "all that" I'll do it. I am pretty sure with all the measurements I've taken and everyone I've spoken with that I can make it happen. If anybody can do it, it's me.
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ir3333
Well-Known Member
... the torque of a 440 is such a poor match for a light A body on the street, but there's no denying the wow factor that comes with tire smoke.
...most 408 strokers usually produce tire spin in at least 3 gears and in all fairness that's gotta' be fun!
I bought this wrecked '70 Charger last year and have a goal of driving it within the 1 year mark of buying it. It was wrecked in 1994 or 1995 and has sat since then.
I've never ported heads but a guy at FBBO posted a video of Uncle Tony's Garage where Tony does a basic cleanup on some heads. I figured I'd give it a shot.
Lookie what $5000 buys you....
You could always run a 440 with 2.96 gears which would give similar torque to the ground as a 360 with 3.55 gears. Allow for better cruising rpm without lost of acceleration.
B3422w5
Well-Known Member
huge bore difference
CPDave
Spin Cycle
Okay, I''l chime in... As to why a 318, I vintage road race and have a rule book I have to follow: https://svra.com/wp-content/uploads/2013/02/Chrysler_Corp-MoPar_64-66.pdf
For me there is a budget, but part of the considerations are operating costs and rebuild frequency. So while I built this to the SVRA Supplemental Preparation rules linked above (which I authored back in 2006), I adhere to the HSR 6800 RPM rev limit (good for 146MPH with the 3.55:1 rear and 25.5" tall 6.00-15 Goodyear Blue Streaks, or 156MPH with the 7.00-15s at 26.7" tall). Not spinning above 7 means this engine can last for 3-5 seasons with a little care & luck. Also running the 3.55:1 rear (which I cannot take credit for, Josh Skinner installed that when he originally built the car from his \6 daily driver) means my on-track mileage is about 3.2-3.8MPG, and running it on pump 93 octane means fuel is 1/3 the cost of Vs. a Mustang running 4.11:1 gears and race gas (35-40 gallons for me over a race weekend). Then I also spec it to turn closer to 7500 just to make sure it's got a long fuse...
Dart's 318 Built & Tuned by George & Justin Reggio at Maryland Performance Center (Home, Maryland Performance Center; 301-371-8883):
0.050" over '69 318 block with Hughs Engines main stud girdle; Scat 4340 crank, K1 H-beam rods, and forged pistons. Milodon 7 quart road race pan, Canton Accusump, oil cooler, and Oberg canister filter.
Comp Cams Mech Roller:
Lift: 0.630" 0.630"
Dur@0.050": 254 260
AdvDur(@0.006"): 284/292
LSA: 107
Int Centerline: 102
Lash: 0.022"/0.024".
QFT 750 Circle Track Carb
Edlebrock LD4B intake with 0.5" semi open spacer
Heads:
Ported by Ryan Johnson at Shady Dell Speed Shop in PA "...302" casting number 318 heads with 1.94"/1.60" valves. Flow @ 28" of water with final intake port volume: 136 cc:
LIFT IN / EX
0.100" 66.1 / NA
0.200" 132.8 / 90.4
0.300" 189.9 / 126.2
0.400" 218.4 / 148.8
0.450" 227.9 / 152.9
0.500" 232.8 / 159.8
0.550" 238.0 / 163.9
0.600" 239.1 / 169.8
TTI Early A-Body headers - 3"-in-2.5"-out X-Pipe and small oval case Borla mufflers.
Static Compression 10.25:1 - runs on 93 octane pump gas
Bore 3.960" & Stroke 3.310"
Rod length 6.123"
After the most recent tune-up in November 2014 (swapped out the mufflers), on a Super Flow chassis dyno, peak power was 363Whp @ 6200-6400, Peak torque 347FtLb @ 4300, Max RPM 6800 (it also pulled 425 HP on the pump at 7000 with the open dyno headers during break-in). Runs on premium 93 octane/10% ethanol pump gas.
For me there is a budget, but part of the considerations are operating costs and rebuild frequency. So while I built this to the SVRA Supplemental Preparation rules linked above (which I authored back in 2006), I adhere to the HSR 6800 RPM rev limit (good for 146MPH with the 3.55:1 rear and 25.5" tall 6.00-15 Goodyear Blue Streaks, or 156MPH with the 7.00-15s at 26.7" tall). Not spinning above 7 means this engine can last for 3-5 seasons with a little care & luck. Also running the 3.55:1 rear (which I cannot take credit for, Josh Skinner installed that when he originally built the car from his \6 daily driver) means my on-track mileage is about 3.2-3.8MPG, and running it on pump 93 octane means fuel is 1/3 the cost of Vs. a Mustang running 4.11:1 gears and race gas (35-40 gallons for me over a race weekend). Then I also spec it to turn closer to 7500 just to make sure it's got a long fuse...
Dart's 318 Built & Tuned by George & Justin Reggio at Maryland Performance Center (Home, Maryland Performance Center; 301-371-8883):
0.050" over '69 318 block with Hughs Engines main stud girdle; Scat 4340 crank, K1 H-beam rods, and forged pistons. Milodon 7 quart road race pan, Canton Accusump, oil cooler, and Oberg canister filter.
Comp Cams Mech Roller:
Lift: 0.630" 0.630"
Dur@0.050": 254 260
AdvDur(@0.006"): 284/292
LSA: 107
Int Centerline: 102
Lash: 0.022"/0.024".
QFT 750 Circle Track Carb
Edlebrock LD4B intake with 0.5" semi open spacer
Heads:
Ported by Ryan Johnson at Shady Dell Speed Shop in PA "...302" casting number 318 heads with 1.94"/1.60" valves. Flow @ 28" of water with final intake port volume: 136 cc:
LIFT IN / EX
0.100" 66.1 / NA
0.200" 132.8 / 90.4
0.300" 189.9 / 126.2
0.400" 218.4 / 148.8
0.450" 227.9 / 152.9
0.500" 232.8 / 159.8
0.550" 238.0 / 163.9
0.600" 239.1 / 169.8
TTI Early A-Body headers - 3"-in-2.5"-out X-Pipe and small oval case Borla mufflers.
Static Compression 10.25:1 - runs on 93 octane pump gas
Bore 3.960" & Stroke 3.310"
Rod length 6.123"
After the most recent tune-up in November 2014 (swapped out the mufflers), on a Super Flow chassis dyno, peak power was 363Whp @ 6200-6400, Peak torque 347FtLb @ 4300, Max RPM 6800 (it also pulled 425 HP on the pump at 7000 with the open dyno headers during break-in). Runs on premium 93 octane/10% ethanol pump gas.
moper
Well-Known Member
I haven't read the other post and I haven't seen much from DeFeo. I like him, but I've been reading his tech since I was a teenager and not much seems to have changed...lol. Maybe I will go read that. As far as this topic -
This is similar to building a proper performance 383. It will take more investment to "make it right". You have to spend to get the results, and there's a perceived expectation of a lower return on investment with the "smaller" engines. I've said since I was 18 that a 318 is only a 340 with poor heads. I broke a ring land on my 340, in a day had the top end and camshaft in a factory built, high mileage 318, and went a won the race the following night. There was very little difference, and that was when I was ignorant of much of the basic physics and knowledge of how an engine works. I know the car was slightly slower. But not so "off" that the general public had a clue what I had done, and by today's standards I broke every rule there is to make it run.
My next comments assume a competent machinist using good equipment because I've seen some real **** attempts at building 318s specifically...
Using 318-sized heads you can get past 1hp/ci just with some decent head work (not porting - but the 5 angle valve job and 1.88/1.65 valves) and a performance piston and HFT camshaft. Using the 360 LA heads or a set of Magnum heads accepting the limits on higher lifts, IMO are better choices for any more power than that - spend money on bigger ports, and use a piston that gets the compression where you want it doing so.
It's an air pump. Make its work easier, give it more air and fuel, and it will respond with more at the crank. I'm sure you (RAMM) can get whatever level you want. Personally I know what most levels of performance will take. I would suggest rather than you targeting a budget figure, you do the exact same work and parts purchasing you would do for a 340 build.
Restrictions are the following: No aftermarket heads of any material. Any OEM style head. No roller cam of any type - even if the block is cast for them. Must run on pump gas, develop a minimum of 12" of vacuum at idle, and idle under 1k rpm.
I think that puts it on par with most average 340/360 builds for street or mixed use cars and trucks.
QuickDart360
Well-Known Member
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