what can i expect from my 318??

[joey]

okay...im trying to figure out what i can expect from my engine...i dont have anything to put it in as of yet but heres what i have..

a dodge 318 block bored .030 over with flat top pistons and a full rebuild kit. i bought rebuilt 360 heads with 2.02/1.60 valves and put those on it. the cam is .443/.465 lift and 280/290 duration...the intake is an edelbrock performer and the carb is a 600 cfm holley. i also bought a mopar performance distributor with the performance curve it came with a mopar orange box too....this combo will have headers

i am wanting to know if my engine will be a dog...i dont want a bogging engine with hesitation...of course i dont have any money now..but your suggestions are welcome

i also might have a perspective vehicle...a 1979 dodge d150...i know..not the best choice...but oh well....if i put this engine combo in this truck with 2 1/2 inch exhaust, 904 trans with 2000 stall and a 3.91 rearend....what kind of 1/4 mile times might i expect....any information is greatly appreciated

[tuffbird]

There wasn't alot of info to go on such as compression ratio, header size, etc...but guessing the flat tops will put you to at least 9:1 compression and running good ole 1-5/8 headers that engine should push about 350hp and 350 ft-lbs roughly.

Running through the 904 to a 3.91 rear though you'll lose some of that gross hp...corrected should put you in the 250-255 rwhp range.

I'd suggest a bit more stall unless you plan on using it to tow as well. It should put the truck in the mid 15s with the 2000 stall, with a 3000 stall you should expect low 15s.

That's a pretty heavy vehicle...why not look for a dart or even a volare to stick that motor into...besides, with it being a truck you may have a traction problem that could rob you of a second or more unless you know how to set it up.

Good luck with whatever you decide.

[Jims451]

What type of cam is that? Are you sure about the duration numbers, they sound pretty big for a cam with such low valve lift. If the cam is truely 280/290 duration it will be a dog under 3,000 RPM unless your compression ratio is 10:1+

[tuffbird]

If I'm reading his cam right it's most likely a Wolverine (Blue Racer) cam.

WG-1161 Hydraulic. This should match his cam card:

Lift Int: .443
Lift Exh: .465

Centerline: 112
Valve Overlap : 61

Intake Dur: 280
Exhaust Dur: 290

BTDC: 33
BBDC: 82
ABDC: 67
ATDC: 28

Sorry, couldn't find the .050 spec on this one but is somewhere in the 205-215 range.

[joey]

a friend of mine has an older model chevy full size truck...it has a throw together 350....basically just rebuilt with an intake, a cam, and a four barrel carb....it has headers and a 3inch flowmaster exhaust....he also has i think a 2500 stall converter in his transmission....followed by 3.73 gears with posi.....

okay my question is...my engine seems like it will have at least the same HP as his...and my rearend should give me a little bit more pull....Why does his truck run high 14s and mine may only run mid 15s....also brand new showroom stock full size chevys run 15.4 in the quarter with nothing done to them.....of course thats the 5.3 liter 280 hp engine....but still...if im having 350 hp i think i should at least be able to top that...

i really dont know what im putting the engine in....my grandad has the old dodge sitting around..thats why i might have tossed it in there....ive had my engine for a little while with nothing to put it in....i just want to see it run

thanks for everyones info

[Karl43]

Watch your compression. The 340/360 heads have 72 cc chambers on them. The stock 318 heads have from 64 - 69 on the ones that I have measured. You do not need very much piston drop to get 9:1/9.5:1 compression which is the best to run on the street. You may want to have the heads milled and/or use a thinner gasket if you can't afford to mill the heads. I have old forged 10.5:1 compression pistons which end up at 9.2:1 compression with the 72 cc heads.

I have a 318 with 360 heads opened up to 2.02 valves. They run great even with a stock 68 340 intake manifold. I have the MP 260/268/44 .430/.450 lift cam. It runs strong through the rpm's up to 6500 (340 rods). Holley 600 CFM Vac secondary and dual exhaust with an H-pipe. My next 318 I am going to try the MP 268/272 .450/.455 lift cam for a little more top end. I am getting at least 17 MPG (need to fix the odometer for a real number).

[tuffbird]

Joey,

This is simply an estimate. I have no idea what you truly have there for an engine and keep in mind that todays trucks are set with net hp ratings...not gross hp ratings.

The software used to determine the outcome of your combo asks for things like true compression ratio, cam specifications, exhaust specs, etc... I had to guess on much of this.

Your gross HP rating is gonna be somewhere in the 350 range but the net hp rating will be about 250 or so. Those new chevy trucks are running 30 more net hp than you would be...the suspension system is better now than it was then, etc...many factors here.

If your truck is set up good, you may be able to get into the 14's. You are hooking up a decent output engine in a heavy vehicle with a 904 tranny and 3.91 rearend gear. Your top speed is limited here. Traction is a HUGE loss...almost a second worth.

The chevy with a 3.73 posi and 2500 rpm stall may be perfect for his cams range.

A 2000 rpm stall for that cam is too little. That's another 1/2 second possibility. Third is a weight ratio problem, too much in front, not enough in back, which again hinders traction.

The newer chevys although a similar problem exists, is not nearly as bad. There was no mention if the D150 you were looking at using was a posi or not...some trucks came with big gears but no posi...if that's the case, add to the traction problem two-fold.

I'm just telling ya like I see it. Others may agree or may disagree...the only fact is, until you get the engine in that truck and run it at a track, none of us will know exactly.

Best of luck...

"fixed the post about gross and net ratings on the engine"

[Doug Wilson]

Stiffer gears, higher stall, limited slip, weighted tailgate open, sticky tires, more carb = 14.7 to 14.9. This is a HEAVY truck compared to the Chev.

[joey]

thanks everyone that replied....

im not sure that i am putting this engine in a dodge d150....it was just a thought....i would love to find me a dakota and drop it in there...

im getting a little discouraged with it just sitting here...im wondering if it will even run...and if it does will i be disappointed...my dad always told me of his 318 with a rebuild, a 340 cam, and some headers that would melt the tires through 2nd gear from the punch....of course he had this in a challenger that was probably a better choice than a truck....there is a decent size crowd around here that races trucks and cars...i would just love to get a mopar out there and beat up on some of them...

any other replies will be greatly appreciated

[T748]

Low 15's would be respectable numbers running the 318.I'm running 14.6's @92 in a 63 d-100 with a 440, thats tipping the scales at 4600# race weight.With nitrous the numbers get down to a happy 13.1 @ 104. My freinds 98 Dodge Ram with a 360 is running 16.6@81 with a 360 on the factory tires.The one thing in your buildup that concerns me is the 904 tranny.A 904 in an A-body isnt too bad but i think in a big 'ol truck it wont hold up too well.-Tom.

[joey]

okay...i will honestly say that i dont know much about engines...i just know what i have used and i have compared it to others who have decently fast rides....for instance

someone spoke of new trucks being rated at net hp when older ones were gross.....i am trying to figure out how a 2000 chevy with a 5.3, 3.73 posi, and a flowmaster exhaust runs 15.4 and the truck i mentioned previously...the old 85ish model chevy with a 350, a cam, intake, exhaust and the same 3.73 posi rearend can blow the new truck away by 3 car lengths....

my engine seems to me to have better parts than his 350 has...and that makes me wonder why my engine will be so much slower than his....all things equal...if both engine were up against each other i would think mine would win....

who knows...maybe i can find a car to put this in...until then i can only dream of hopefully beating people...thanks to everyone that helped

[tuffbird]

Let's take this to its simplest terms.

The 2000 Chevy Silverado with the 5.3L is "rated at 270 Rhp". In all honesty, if you stick it on a dyno, the actual rear wheel horse power of that truck is going to be somewhere in the 240-250 Rhp rating...not as GM states. Besides, hp is really not a consideration without accounting for the torque the engine can generate...which is just over 315 lb-ft...which may be a bit over-rated as well.

That Silverado also weighs in at over 2.5 tons with a driver...so given the flowmaster exhaust this will put his truck into the 250-260 Rhp range and there should only be a 5-10 ft-lb increase at most in his torque rating.

Note his engine is a 327cid. Rhp = Road Horsepower or net hp.

I also highly doubt the 1/4 mile times of this vehicle since all road test I've been able to find show it to run high 16s and low 17s. Simply adding a cat-back flowmaster system to the truck is NOT going to put it into the mid 15s.
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The 1985 Silverado has a 350 (or 5.7L) that has had the typical chevy mods done to it...This truck would tip scales with driver at somewhere just over 2 tons...less mass to push than the newer truck.

Originally that motor was built as a conventional workhorse and the power output on it was around 200 Rhp. This is mainly due to the amount of smog restrictions and crap they had to choke the engine with.

If an owner was so inclined to ditch some of these parts, the 350 could be opened up to about 250 Rhp easily.

You stated it was a basic rebuild with, I'm assuming, the addition of an aftermarket camshaft (crane or Compcams maybe?) and intake (edelbrock or holley?) and a 4bbl carb (650cfm?)
If he added ANY performance mods in these three (mainly camshaft) then he may have boosted HP to around 310 Rhp or so if everything is tuned in. Given the headers and a 3 inch exhaust system I'd wager he added another 20 hp to his number

His torque may be around the same or higher if his selection was thought out before his purchase...regardless of his basic engine rebuild.

He could easily be pushing 320 Rhp or NET horsepower. In a 2 ton truck with that stall (which BTW, puts him starting right in his power band) and those gears, sure...he'll run high 14s / low 15s all day long...which is about 3 or 4 car lengths ahead of the newer 1500 with the 5.3L.

I can only assume he chose that stall because of his camshaft.
_________________________________________

The 1979 D-150 weighs in at approx. 2 tons (a little over with driver).

Your 318 on my dyno program was measured at 352 Bhp or Brake Horsepower...that is the engine by itself with no actual load ...also known as gross hp. Gross HP ratings were used until midyear 1971 when the industry switched to NET hp ratings.

Given that there was no load occuring on your engine with the configuration specified you must assume a loss of 17-22 percent for an automatic transmission, drivetrain, etc... So lets say your looking at 20% as an average. This drops your 352 Bhp to 280 Rhp. Knowing that there is usually a fudge factor in calculated vs. real output, you chuck about 20 more hp off of expected output. So now your engine is in the 260 Rhp range.

The cam you selected really picks up at 2500 rpm and pushes hard to 5300 rpm. You want to get in your power band as quickly as you can. If your converter flash stall is 2000 or less, the engine will have to deal with the decreased power output before your truck gets moving. Moving to a minimum 2500 rpm stall would put you at the start of your power band....a 3000 rpm stall would drop you in the thick of it...but then you loose towing power...which is typically needed in the lower rpm ranges.

Here are some suggestions for getting the truck engine combo ready to beat some chebbies...

1.) Increase your cam advance by 4 degrees. By changing the timing gearset...not by simply moving the distributor. This should have a profound effect on the cam, timing and overall output of the motor.

2.) Uncork the headers from the exhaust when racing...buy some cutouts that you can use before racing (this usually shaves a good 8/10th off.)

3.) Buy an Edelbrock Air-RPM intake...great for keeping the intake charge cool...increases hp a little.

4.) Pick up some 1.6:1 rocker arms and increase your lift a bit. This will give you some extra hp as well.

5.) Buy some Nitto or BFG Drag Radials...before a run, drop the pressure to 15 psi or so.

6.) Build a box for the truck bed and add a couple of cynder blocks behind the rear wheels...better traction.

7.) Use an electric fan instead of the Viscous fan.

8.) Take the truck on a weight loss plan...dump the carpet, bumpers, inner front fenders, radio, AC/Heater stuff in the truck

9.) Get those heads bowl ported and gasket matched.

Any of these are going to shave some time off...all of these should put your truck into the high 13's or low 14's easily.

But especially don't give up if you drop the motor in the truck and get beat the first few rounds...

My 72 Roadrunner with a 440/4bbl just got put back together and my first track pass yielded a 14.223...with tire pressure changes, jet, squirter and power valve changes in the carb and a timing adjustment and changing from a 3.23 open to a 3.55 sg unit, it now runs low 13's after 4 months of tuning...right where I want it to be for now.

I expected the car to run in the high 12's...and may just do so with the weather dropping out of the 100s into the 80s here in Texas.

[T748]

Just to throw my two cents onto Tuffbird's recipe ,heres the two best additions i put on mine for making rounds at the track.A set of Drag radials and rigging up a pinion snubber.The snubber will keep the wheels from hopping. No matter what engine mod's you do,getting a truck to hook off the line is the key to running a number.

[Darn Dart]

My buddy has a 78 Little Red Express Truck with a very mild 360 that has a run a 9.10 in the 1/8th mile, that would be about a 14.20-14.30 in the quarter. It is a stock rebuild with 9.5 KB pistons, stock rebuilt 915 heads, stock spec cam, stock torque converter, mild B&M shift kit, stock 3.55 gears. The only performance mods are 1 5/8" headers, Weiand dual plane and a 600 Holley carb. The rest is the way Ma Mopar built it. He runs McReary G-60-15 Dirt tires(soft compound). The big old truck makes awsome power, and idles like a stocker.

[Dennis Jokela]

IF YOUR PISTONS AR STOCK FLATTOPS, AND YOUR HAVE 360 HEADS THAT HAVE NOT BEEN MILLED AT LEAST .050 YOU WILL HAVE A COMPRESSION RATIO OF HITH 7 TO 1 OR 8 T0 1. THAT MOTOR WILL NOT LIKE 2.02 VALVES AND NO COMPRESSION.

I WOULD MILL THE HEADS AT LEAST .050, AND ADVANCE THAT CAM A FEW DEGREES OR IT WILL NOT HAVE ANY BOTTOM END.

I WOULD INSTALL IT IN A A-BODY OR IF YOU LIKE TRUCKS A D-50 DODGE PU.

DENNIS

[joey]

about milling my heads....i didnt know how much i could mill them....i also didnt know if i would have clearance problems with valves and pistons....like i said before...i dont know much about engines....but if i set the combo up the way it is now...and run a 2500 stall converter....am i mistaken thinking that i will have a decently fast ride....

thanks for your help everyone

[joey]

my engine may have a home...but its still up in the air right now...

the prospect is a 1972 duster...its a gold duster that came with a 318, a/c and p/s...let me know what kind of times i can expect if i put my engine in this car...my brother things his 99 sonoma is gonna beat me...i said no way because it only runs low 16s...

anyway...let me know what yall think of my choice and what i can do to get the most out of it...

ill let yall know if i get it..thanks