Another 318 Thread

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JoJo

JoJo

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I've tried to search for a few threads that are based on 318 setups. I'm trying to see what most people run in the 1/8 mile with them and see what their setup is. I have a 318 that came out of a Diplomat. So far, it's stock except for the exhaust, intake, and carburetor. I'm wondering if mid to high 7's for a 318 is reasonable... All opinions are welcomed.

I already know someone will say, "Don't waste your time, get a 360!"

:D
 
JoJo, what car would this be in? Weight, gearing, trans, converter, etc. For a 3400 lb. car, driver incl, that has the proper gear and converter along with a good suspension setup and traction for a good 60' time, i would think 350 hp would get you in the ballpark. That's doable in a teen with lg. port heads, decent compression and a cam for the specific combo.
 
The setup is currently in a Dodge Dakota. I want a Dart or Duster, but I haven't got my hands on one just yet.

Weight: Factory weight is around 3,740 lbs. if I'm not mistaken
Gear: 3.08
Transmission: A904 w/ TransGo TF3
Converter: Stock

Last time out at the track...

60' - 2.336
330' - 6.544
MPH - 53.87
1/8 - 10.077
MPH - 69.69
 
What year Diplomat? Roller cam,flat tappet? Do you deal with smog inspections?
 
I want to say an '87... It has the roller cam. No, I don't have to deal with inspections.

Here is a pic when I first rebuilt the engine...

4qpj0g.jpg
 
Is this a full build or mainly bolt on's? are you willing to do porting? Budget? Is driveablity an issue? Cam 262ish , headers and gear 3.55+ would make a big difference 280ish hp that would be a start. Above that Stock CR and head flow become an issue.
 
Up front most are gonna tell ya, go 360.
Hey, I love 318s... If you beat someone you can really rub it in their face,and if ya get beat it's, " it's only a 318 grocery getter".
My Dart is a '70 with no lightening, I guess I'm around 3500 with me in it.
318,904, 8-3/4 w/3.55s, 225/70-14 TA radials. Manual steering and brakes. Yes, it's got all the usual suspects, 600Eddie carb and manifold, headers into 2-1/4" duals, a little cam and heads shaved for a little more compression. It's a DD to the tune of 5000miles in the last year.
Last trip to Atco netted a best run of:
60' 2.154
330' 6.046
1/8 [email protected]
1000' 12.0
1/4 [email protected]
It might have another .2 and 1 or 2 mph in it as it sits with better weather.
Surely a couple more tenths past that when I put the 4.10s in and sticky tires.
I'm sure you could do a streetable high7-8.0 318 driver very reasonably (just not a great highway car).
 
I'd like to know where this ends up, as I also have an 87 roller 318 I'd like to massage a bit. I'm especially curious about cams and realted valve train issues. Hard to find info on pre-Magnum roller motors. I'd like to keep the roller, but want something more. If I can't find a roller grind, I wonder if I can just put in a flat tappet grind like the comp XE series and still use the roller lifters.
 
YY1: you can not use roller lifters on a Hyd. Or solid cam.
Just search out the roller cam you want or call up the cam company and say you have a roller MoPar/318 and seen xxxx cam in there book. The. Ask then to make something similar to it on for a roller cam.

Basicly treat the roller engine as a regar engine. The only valve train difference is a shorter pushrod. Everything else is the same. Since your getting a new cam, the springs will be changed out for the matching springs for the cam and new retainers will be added in if the old ones won't work right.
 
Your roller cam 318 is a great place to start. There is also a good chance you have #302 casting heads which is also a bonus. tmm
 
It does have the "302" casting heads. I want to keep the short block stock and play with the heads and bolt-on parts to see where it lands me. Right now, my gears are a major drawback, but does great on the highway. I was thinking of headers, roller rockers, porting and shaving the heads, camshaft upgrade, and converter.
 
They should have a 318 only Thread just to keep the 360 guys out.Keep searching you will find what you are looking for.Try some 273 threads they may be helpful to you also. Mark
JoJo said:
I already know someone will say, "Don't waste your time, get a 360!"

:D
Click to expand...
 
I'd be careful about milling the heads if you plan on doing a rebuild on the short block later and gonna do the zero decked, 0.040" gasket Quench thing because the stock 302's 59cc chambers gonna give 10:1 so any milling will give too much CR later. Problem is the stock CR right now is low to mid 8's which limits cam selection need 9:1+ to be able to use decent cams 265-280 range. Pistons are the only proper way to get CR out of a 318 or mill the crap out the heads for now and upgrade to better heads when do full build and sell your temp heads after to someone looking to hop up a stock short block but even without milling I would install bigger valves and porting the heads thinest gasket you can get and high lift 262 cam and headers will get you close to 320hp more CR and a bigger cam 350hp.
 
JoJo said:
It does have the "302" casting heads. I want to keep the short block stock and play with the heads and bolt-on parts to see where it lands me. Right now, my gears are a major drawback, but does great on the highway. I was thinking of headers, roller rockers, porting and shaving the heads, camshaft upgrade, and converter.
Click to expand...

JoJo, i generally agree with your thinking as to further mods......But, there's always a but......lol. I think you first need to decide if a "A" body will be in your future and when? Problem being that except for the headwork, nothing will really interchange between the "A" and the Dakota. Cam & Converter choices will be different because of weight and the gearing you'll probably choose. Not to mention the headers wont be correct either. What i'm trying to say is, you may want to try to avoid buying the same parts twice. If you think you'll be in the Dakota a while then have at it, but if that's not the case, i would just tinker a little with the Dakota to have some fun and hang on till you get that Duster, Dart, Demon, whatever.
 
273 said:
I'd be careful about milling the heads if you plan on doing a rebuild on the short block later and gonna do the zero decked, 0.040" gasket Quench thing because the stock 302's 59cc chambers gonna give 10:1 so any milling will give too much CR later. Problem is the stock CR right now is low to mid 8's which limits cam selection need 9:1+ to be able to use decent cams 265-280 range. Pistons are the only proper way to get CR out of a 318 or mill the crap out the heads for now and upgrade to better heads when do full build and sell your temp heads after to someone looking to hop up a stock short block but even without milling I would install bigger valves and porting the heads thinest gasket you can get and high lift 262 cam and headers will get you close to 320hp more CR and a bigger cam 350hp.
Click to expand...

Don't think I will have the block zero decked. I just rebuilt the engine back in April and decided to not touch the block. I was peeping at the Mopar .025 Head Gasket to add and milling the heads some.
 
OldmanRick said:
JoJo, i generally agree with your thinking as to further mods......But, there's always a but......lol. I think you first need to decide if a "A" body will be in your future and when? Problem being that except for the headwork, nothing will really interchange between the "A" and the Dakota. Cam & Converter choices will be different because of weight and the gearing you'll probably choose. Not to mention the headers wont be correct either. What i'm trying to say is, you may want to try to avoid buying the same parts twice. If you think you'll be in the Dakota a while then have at it, but if that's not the case, i would just tinker a little with the Dakota to have some fun and hang on till you get that Duster, Dart, Demon, whatever.
Click to expand...

The 318 will most likely stay in the Dakota after all the trouble I've been through. Hopefully, I will find an A-Body with a 318 or 360. If I find a roller, a 440 may be on the menu.
 
rumblefish360 said:
YY1: you can not use roller lifters on a Hyd. Or solid cam.
Just search out the roller cam you want or call up the cam company and say you have a roller MoPar/318 and seen xxxx cam in there book. The. Ask then to make something similar to it on for a roller cam.

Basicly treat the roller engine as a regar engine. The only valve train difference is a shorter pushrod. Everything else is the same. Since your getting a new cam, the springs will be changed out for the matching springs for the cam and new retainers will be added in if the old ones won't work right.
Click to expand...

Forgive my ignorance, but why not?

I'm not sure I've seen any evidence to suggest the LA roller motors even used an aggressive roller profile cam that was any different than a regualr flat tappet grind.

Wouldn't the rollers follow a standard lobe just as well?
I understand the push rod length may have to be adjusted.
(but then again, maybe not)
 
YY1 said:
Forgive my ignorance, but why not?

I'm not sure I've seen any evidence to suggest the LA roller motors even used an aggressive roller profile cam that was any different than a regualr flat tappet grind.

Wouldn't the rollers follow a standard lobe just as well?
I understand the push rod length may have to be adjusted.
(but then again, maybe not)
Click to expand...
Ever looked at the 2 cams side by side? Big difference in the profile.
 
I have the intake off the roller motor right now, but my 73's are buttoned up.

Specs for those stock 318 cams are kinda hard to find (although I do have what I could find), and it basically says the same thing- 240/248 373/399, and I'm surprised it's a split profile.
 
In fact, I'd love to see all the stock 318 (and 360) cam specs side by side.

67-86 LA (and any variances for different compression years)

87-91 roller LA

92-96 Magnum

Any time I find any specs it just says "318".

At risk of a hijack- I ve heard the 5.2 cams are hotter than the 5.9, but can't find proof.
I've heard the 92 5.2 is even hotter.

...and I'd like to know if you can run a 5.2/5.9 cam in a roller LA (with the pump snout).
 
I would bet many of specs are quite similar, but, as inkjunkie mentioned roller and flat tappet are physically much different...
On flat tappet cam the lobe acts on the whole.904" diameter of the (very slightly convex) lifter face, a roller only on a virtual point (roughly centerline of lifter, contact moving only a tiny bit for or aft of that axis depending where on the lobe the roller is)....
Now if you could make your roller the same radius as that of the face of your lifter, your cams would be very similar... but I'm guessing your rollers would be about 9 feet in diameter at that point...
Oh, and that's not taking into account that your flat tappet lobes are also oh so slightly tapered from one edge to the other to keep those lifters turning/spinning in their bores...
I'm pretty sure you can get magnum cams with a pump snout by special order.
 
I'm sure someone else will school me even more here.
The musings on that roller, not only does that contact move back and forth ( in reference the the rollers axle/axis) but up and down too...
wow! I need to go to sleep before I start playing in some CAD/modeling programs.


:coffee2:
 
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