High 13's out of my 318?

I have a duster that I am bracket Racing.I don't have very much money.I have run a best of 15.72 in the Quarter mile.
Here is my set up.
68 318
600 cfm edlebrock carb with a performer intake
j heads 1.88 intake 1.60 exhaust
340 manifolds
727 transmission
8 3/4 rear end 3.55 suregrip.
Cam is 260/268 Duration 430/450 lift.


I don't want to hear go to a 360.This is what I have.
I just want to go a full second faster.
3.91 rear end is in the works.
Thank you to all who repley.

What convertor?

What camshaft are you running? I think headers will help you. Not big honking race headers, you want smaller primaries for that smaller engines torque.

A good budget converter
A better intake (performer RPM)
Headers
Cam in the 235 @ .050 range (thinking summit lg. Cam)
3.91's
Strip the car of ANY extra weight.

Should be a pretty solid 13 second package.

What MPH and RPM are you trapping at now?
Cam lift and compression are what normally needs to be addressed in a 318.

I am sorry The Cam is 260/268 duration.430/450 lift

If you didn't mill the heads a fair amount, the cr is likely pretty low.

Do a compression test and see what cranking pressure is now before thinking about swapping in some big cam.

If ET is really the goal....Put headers on it, use plenty of stall & plenty of gear.

You don't want to hear it, but the reason people are going to tell you to do a 360 is because in the end, that's really the best way to get where you want to be.

This was my combo in my 70' Dart w/ 318

340 iron intake
Thermoquad carb
The cheap headman headers (small tube)
484 purple shaft cam
un-ported 360 heads
4.10 8 3/4
26" Mickey Thompson Street ET tires
lame converter
manual valve bodied 727
Full exhaust
60' in the 2 second range (garbage converter)
Best ET 14.02 @ 102mph, Would run consistent 14.1x @ 100mph all day

If I had a good converter, would have gone in the 13.xx no problem. Loads of fun on the street from a 20 roll

Gear and good convertor are your best friends with a little motor

Best bang for the buck is a small plate of NO2.

318 @ .030 over
Eddy Alumn. single plane intake
750 race Proform carb
headman headers (small tube)
484 hyd. purple shaft cam
Worked 318 heads
4.10 8 3/4
27" Mickey Thompson Slicks
4200 converter
manual valve bodied 904
Full exhaust
60' in the 1.90 second range
Best ET 13.93 @ 102mph, Would run consistent 14.00x @ 101mph all day long.

Should have kept that combination, very simple and very easy on the pocket book.

Not needed. Way to easy to do it with a 318 to need nitrous. Why do guys always choice the EASY way??? Take some pride in yourself and get your hands dirty.

THIS/\

'71 ring and bearing 318. Very loose!
360 J heads with 1.88 intake
.480 comp hydraulic cam
M1 Single plane
750 Holley 3310
Cheapie headers, 2.5" exhaust, turndowns at axle.
2500 stall
3.23 gears

3460 lbs.

I managed 95 mph in the quarter which equates to 13.6-ish. I only got it to run 14's on crappy 245 street tires.

He wants to go racing and doesn't have much money

My 318 numbers in my signature. Could be a good bit faster with more upgrades to the car around it.
Some of which I am going to do over the winter.

I am launching in 2nd gear(column auto) 1st to 2nd, and shifting at about 5200 rpm.

Like everyone else said, more gear converter and cam. 4.30-4.56 gear, super short tire if you are stuck with 3.91, 4000+ converter and the biggest solid cam you can fit. The cheapest way is never the most efficient or streetable...

3.91 gear is a good start. More will be needed shortly, though. A compression test will give you a good baseline number. From there, I would pull the heads for milling. If pistons are deep in the bores, the block should be decked, too. But I understand money is a concern, so the heads would be the cheapest compression increase. Use OEM steel shim gaskets to keep compression up. A nice cam in the .480 lift area shouldn't hurt the pocket too bad. Install it advanced. If you don't have the funds to upgrade the intake, put a 1" spacer under the carb. You will need to determine if it likes a 4 hole or open spacer best. Small tube headers and a decent converter. If you are running a stock converter, I'm sure anything you can find 2,800-3,500 rpm will do fine. Start gutting the car. Spare tire and jack, back seat, passenger seat, heater box, wiper assembly, radio, amp, a/c.

I don't know how thin your budget is, but you can do some changes for cheap.

First, keep the 600 and performer manifold. They are plenty adequate.

The CR is going to be really low. Either mill the heads, or change the cam to a modern lobe to get the cylinder pressure up, or both. Something like a Lunati 10200701 would be my choice.

Add a set of 1.6 roller rockers, properly set up of course. Here is where I can really help.

Skip the 3.91 gears and go straight to 4.10. 4.30s might be better yet for a 318.

If possible, ditch the 727, and put the 904 that's supposed to be there back in with a true 3000-3500 converter. Your wasting efficiency with a heavier than necessary transmission.

Bowl port, or have ported, the j heads, and port match the manifold.

1-5/8" primary tube full length headers.

If you can do everything except the machine work yourself, you should be able to stay under $2000.

If a low compression 360 with this basic combo can run 12.90s, you should have no problem going 13.90s with your 318, unless it's just plain wore out.

thank you Mike

You're welcome. I want to note that a lot of this can be done incrementally to make it less painful for the budget. Considering gears are already in the works, I'd go there first, and do the trans/converter next, saving the motor for last. You should see a big improvement before you get to the motor, and more once the whole combination is optimized.

I agree with fast68 110%. Look for forged pistons for a 318, see what you find. The aftermarket starts at 4". IF you want to do some work, put a GT 45 turbo on it. My stock headed 318 makes north of 536hp&586ftlbs.Dave

Some good forged ones here priced right and the seller will go a hair lower.

http://www.ebay.com/itm/WISECO-Pistons-PTS529A3-Chrysler-Mopar-318-3-940b-3-310s-6-123s-5cc-9-7-1-/272340296148?hash=item3f68bf21d4:g:f2sAAOSwLF1X~k2S&vxp=mtr

Ummmmmmmmmm, Isn't that TWO seconds faster?

After that - B3RE's suggestions are spot on, especially switching to the 904, and I would add to that idea to find a low gearset trans core to build up. Actually I would do the trans swap first - you reduce the power lost through the trans by about 20 hp, you save weight, and the 2.74 low gear/3.55 axle is a slightly better ratio than the 2.45/3.91 combo.

After that, more compression, a cam selected to optimize cylinder pressure, and small tube headers will be your best friends.

I have run low 14's on street tires with a 318 Dart with a stick, here are my suggestions.

1) 3.91's will do fine assuming you have proper traction. Slicks are a must, pickup a used set if you have too. Local swap meet had several sets of good M/T slicks for $100 a pair. I had to resist picking up spares, lol.

2) Throw the manifolds in the trash or Ebay. I just swapped from manifolds to headers on my small block Duster and after some tweaking the car picked up 1.1 seconds and 70+ hp.

3) The heads are a bad match for the engine. No port velocity for a small motor and the compression is in the toilet. My suggestion which will run counter to some folks advice is to replace the 340 heads with decent 318 heads. This will raise the compression and increase the port velocity and get things in line with the cam and displacement you are running. Magnum heads would be a nice balance but extra expense in finding correct push rods, uncracked heads, redrilling the head or intake swap, etc..

With that cam and intake you are going to top out at 5300-5500 rpm, just when the 340 ports are really going to start going. You are losing a bunch of torque which you need to maximize to make the most of the package. To get the 340 heads to work proper you would have to mill the crap out of them which causes more issues, match the cam to the heads, looser converter, a lot more gear and spin the motor higher in my opinion.

4) A 904 would be a better choice- Less mass and better first gear (assuming you had one with 2.74 first gear ratio) but just keep the 727 for now and pop for a better converter when you can.

My old Dart had a 69 318 with 1972 318 heads, 455 lift DC cam, blackjack headers, LD4B intake with an AFB off a 273 with a 4-speed and 3.55's out back with street tires.

On 3-12-89 the car ran a best of 14.2 at 96 mph with a 2.34 short time

If I had a pair of slicks, the car would have been rattling off 13's all day.

In short- Headers, gears, slicks and replace the heads.

Hope this has been of some help.

Gary

Good call ES. I failed to mention the low gear set for the 904. The trans and converter swap could be the starting point, but I suggested the gears because the OP mentioned they were in the works. Either way, there will be a noticeable difference in performance.

1) 3.91's will do fine assuming you have proper traction. Slicks are a must, pickup a used set if you have too. Local swap meet had several sets of good M/T slicks for $100 a pair. I had to resist picking up spares, lol.



Slicks aren't a MUST anymore. M/T radials will run quicker times.

Slicks or drag radials, with the caveat that drag radials are less forgiving then slicks to chassis setup.

And I have yet to see a used set of drag radials for sale at a swap meet. He is on a budget remember?

Everything I have suggested works and he would be in the 13's for under $500.

Cheap set of 318 heads, gasket set, $75 set of headers (or less, I just sold a used set for $20) if he sells off the 340 heads he could actually get a chunk of his funds back.

I have done the 340 head swap for two people and they both came out the same way; poor torque with little payoff on the top end.

I'll add that if some 318 heads are used, I'd mill those some too(say .030-ish), install the 1.88 intake valves and do a quick bowl blend.

The 360 heads definitely make more power IF you build a motor that can take advantage of them.
In the early 90's I built a few 318's for one of the oval track teams around here.
They had been running the 302 heads previously.
The head rule was any stock head, max valve sizes 1.88/1.50, no porting of any kind.
I'm sure this was a mistake in the rule book, but it had been in there for years, so I went with it.
The other rules were oem 2bbl manifold with holley 4412, flat tappet cam, 10:1cr, flat top stock type pistons.
I used trw forged, decked the block, milled the heads to get to that cr.
I freshened a set of the 302 heads they were using and installed the 1.88 intake valve.
I also prepared a set of 596 heads, and did the swap on the dyno.
The motors for this class had to make at least 340-350hp to be a top runner, and what they had been running with the prior year with the 302 heads were not competitive.
They had good sized fast rate solid cams and would turn 7k at the bigger tracks.

The 596 heads were about 40hp better than the 302 heads in that application.

But I don't think the combo the op is working with would be able benefit from them without stepping it up quite a bit.

Oh yeh...... Those 318's I did won a couple of championships
Along the way they got torn down more often, and had more things checked than anyone else in that series ever had been.
Always passed tech........ followed by plenty of head scratching by the tech guys.

Assuming the weight remains pretty constant, to go from a 15.7x to a 13.99 is going to take about another 80hp, plus the ability of being able to put that added power to good use.

Not to keep harping on it........but.....
You could probably find a re-ringable 360 short block for as little $$$ as any other option and just reuse the complete top end.

I'm going to agree with the one who said the absolute cheapest way to get there is a 75-100hp shot.
Probably not the cheapest long term, cuz you gotta keep filling the bottles..... But it would knock over a second off for a couple hours installation time.

This^
Not sure why more mopar guys don't embrace power adders...



How does using a power adder reduce one's pride?
Are you implying that getting a N2O car to run properly is easier than an NA car?

If I was going to have a 13 second car, I would much rather drive around with 3.55's and a tighter converter than to have to deal with a 4.xx gear and loose converter.

904 low gearset transmissions, aftermarket converters, 8 3/4 pumpkins, headers, cam, and head work can add up quickly.

I'm not sure it could get any cheaper than an ebay turbo with reversed iron manifolds, and blow through on E85, or a 125 shot under the carb. I picked up my first plate kit for $150 with a full bottle...

Today's society is ALWAYS looking for the easy way. Push a button to run 13's makes me LMAO. How pathetic.

I beg to differ here. The 22 cubic inches between a 318 and a 340, does not make a small valve j head lose a bunch of port velocity. What you have suggested is a small port/big cam scenario. The cam is 15 degrees larger than what I suggested, and will hurt torque more than the additional port volume will ever do. Then, when the cam starts to really work, the heads start to choke the motor. You would end up with a very peaky motor that has no low end or top end. A larger port like the j head with some bowl work and a small cam, will have better volumetric efficency across a broad rpm range, and make power both lower and higher than a big cam/small head combo.

On the gears, a lower ratio, like a 4.30, will allow the car to pull harder through the first half of the track, which is where et is found. The smaller cam will help the bottom half as well, and the larger ports will help carry the torque curve higher and keep the motor pulling on top end. As long as the trap rpm is around 5800-6000, shifted at roughly 5500, it will be quick.

The OP was looking for CHEAP...just happens to be that the cheapest option here probably is not to rebuild the 318, install a new trans and a new rear gear...Probably want to throw a purple shaft in there while you're at it...




Turbo 318 Dart:
https://www.youtube.com/watch?v=B74ACQbowas

Nothing wrong with power adders. They are a smart choice if you want driveability and performance in a street car, especially if emissions requirements are a factor.

The OP said he was Bracket Racing. I didn't make any assumption that it was a street driven vehicle, because he didn't say it was.

Dwayne, with 3.55 gears, I'm certain he isn't trapping at or above peak power, so the additional rpm from a better gear will automatically show as higher hp in the mph. The motor probably only needs to pick up 50hp or so.

He already has the purple shaft, in case you missed it. Oh yeah, I recommended changing it.

Did I say rebuild the 318? I must have missed that.

The gear change decision was already made by the OP. I merely suggested a different ratio.

A new trans? No, a different trans IF POSSIBLE. That means if he has one readily available for cheap. Sounds like you May not have read the thread thoroughly.

A good converter will the best money you can spend on the combo. Getting the car to 60' is essential to running decent et's. Get a good 9.5" that flashes hard to the high 3K range that is still fairly tight for normal driving. A good converter company can put one together in the 450-650 range is my guess.

Plenty of 11 second engines in 16 second chassis's out there!

Your carb and Performer 318/360 is fine for the combo. Get the ignition timing initial/total sorted out as there is FREE low end power trapped there

A low gear set 904 with the proper converter could net you most of a second. That motor is a terrible mismatch, I have nearly identicle motor sittin in the shop floor right now at 6 to 1 compression, performer intake... 360 heads plus the thick .054 fel pros the guy had on it were terrible, he picked up a bunch going from a 727 to a low geared 904, it was a terrible dog before the swap even in a kindo light gutted 73 dart. After the swap it felt like someone released the e-brake.

Later we swapped in a 360 2bbl long block napa re-build with his performer intake and I added .028 head gaskets (napa used the thick fel-pros) and it was faster yet.

You need to do something drastic about the compression after the trans swap or run a 4.10 and real loose converter to make up for the non existant TQ.

Don't tell the pro engine builders about another trick I have used to get compression on the cheap, I buy the mr gasket steel shim head gaskets, remove the rivets and use the black coated outer layers for individual head gaskets just like the original steel shim factory gaskets that seemed to last forever.

I don't know why some guys have so much trouble getting a 60ft time, my first drag car I had a mostly stock 76 360 (360 2bbl cam 318 heads, iron 4bbl intake, t-quad) in a 66 dart and could pull off a 2.0 flat 60ft with no posi and a 215-70-14 street tire. Find some stiff rear shocks, make some spring clamps and put two clamps on each side front half, remove the rear spring clamp bands, get some 6 cyl t-bars, find some front shocks that pull out real easy (I don't remember what I ended up with but I went to all the parts stores, asked to see all the front shocks they had listed for the car and pulled on em all till I found the loosest one, old front end parts with lots of fresh grease, I added manual brakes, manual steering, battery in the trunk as far back and right as possible, kept the fuel tank full and practised a lot on the street, then when I was at the track hooking came natural. I won trophys with it in the foot brake bracket class because I could make it consistant, launch relatively hard, and had no top end so the other cars though something was wrong with my car.

oh and at least while you got the intake off match the port exits to the big heads, the performer ports neck down bad to fit a 318 head and will ruin any flow benifit from the bigger heads.

I was thinking maybe some JY magnum heads, (yes they will be cracked, but run them anyway). They will bring the compression up with the smaller chamber size and flow better than the J heads. They have a 1.6 rocker that will make your cam appear a little bigger also. Then add thin Mr. Gasket head gaskets, JY GM 3100 springs and retainers, crosswind air gap intake and a cheap set of 1 5/8 headers. Add a 4.10 gear set with 26" tall tires and 3000 converter. Should put you where you want to be.

Without knowing what the budget really is, I'd say these are the things I would address first, $$$ permitting.
-for more power, mill the heads and try and get as close as you can to 9:1 without going nuts.
While they're off, a quicky bowl blend would be nice.
Install some cheap long tube headers.

-for the car, way more gear, and as good of a converter as you can afford.

The cam he is running is fairly small and very close to what I was running back in 1989.



Are you forgetting the catastrophic drop in compression running 340 heads?

Been there, done that. Cars with piggish throttle response and no torque are not fun. This I would imagine is what would explain the original posters dismal track performance.

My 318 Dart with "small port" heads would have have his car as it sits for lunch and spit the bones out.



Shall I post a time slip? I have already run the package suggested and it is track tested. The car made buckets of torque but was done by 5500 which is fine for the application.

The guy wants to run 13's, not reinvent the wheel.

I ran a couple numbers......

Assuming 68cc j heads, the "normal" passenger car cast type flat top piston with 4 small valve pockets, which should be down the hole about .080 and std composition head gaskets......
About 7.9cr.
It would take getting rid of about 12cc's to go from 7.9 to 9.0cr.

A thinner shim style gasket would get you about 4.5 of that, and if you milled the heads .045 or so you'd get most of the rest of it.

My 318 has dipped into the 11.70's at over 3400 pounds. It's not rocket science.
I have a dinky hydralic cam. It's 231/238@50.
Not much gear(4.10 with 28 tall tire)
Key is good heads( I have magnum RT's with 2.02 valves) good machining, and some compression... 10.44
Have a tight 8 inch convertor that helps a bunch. Car had been best of 1.639 60 foot on leafs with ultra cheap shocks. That is an area that needs work
This still with stock water pump and fan, and power steering. I would think high 13's should be no sweat with just a couple of things done right. Convertor being key, along with some modest compression.

Didn't Goody get his 318 cuda (heavy) into the 13's with nothing really crazy at Las Vegas which is notorious for crappy air?

Not a 318, but still low buck...... And not an a body either.

My Dads 79 Cordoba. This was a pretty bare bones car for a Chrysler. No a/c, no power windows, no cruise, no tilt wheel. Still..... Weighed 3960 with him in it.
360/TQ/lean burn, lock up trans, 2.76 gears.
Got some junk yard 3.91 gears out of some van, welded up the spider gears.
Put some bald g60-15's on it.
Got rid of the lean burn stuff, added headers.
Went 15.15 first time out.

He wanted to go faster.
Bought a pretty clapped out 71 fury 2 door that had a 360 2bbl.
71's had flat top pistons, not dished pistons.
Left the rotating assy installed and untouched.
Pulled the heads and tore them down, did a good job of removing the carbon from everything, installed some hp type single springs and new seals.
Got a used .480 lift cam at a swap meet, shoved that in.
He ended up using the 727 and converter that came out of the fury.
Back to the track....... 13.90's.

Got a swap meet early style Torker and a Holley 650dp. Went the same but ran much better.

After that he spent a little money going through the original motor and it was running mid-12's with slicks and a decent converter.
That was still a pretty mild build..... 8.8cr, pocket ported heads w 2.02 valves, and the 509 cam.
That was like 1990-1991. I dynoed the motor, it was right about 400hp, but I don't recall if it was just above or just below 400(I wanna say it was 398hp......I might still have a dyno sheet in my files).

this

And just as important(or probably more so), the skill level of the op to be able to do the bulk of the work himself to make each $$$ go a little farther.

Again, re read the thread. The compression part was addressed. Just what do you think a static compression ratio does besides raise cylinder pressure, and cylinder pressure makes torque. It can be manipulated with the static compression ratio, or with cam timing events, or both, which is what I said. Even at 8.5:1 CR respectable performance can be had.

The cam he is running is 221@.050" on the intake, and the lift is only .430". Compare that to the Lunati that is 213@.050" and .454" lift. The shorter duration and higher lift is going to fill the cylinder better on average, and I also suggested a 1.6 rocker to give even more area to an already better lobe. Now, the cam you said you used has 228 degrees @.050", and the same lift. That is 15 degrees bigger than the Lunati, and coupled with small port heads and relatively low lift, is going to have a narrower power band than the smaller cam and better flowing heads. Period!

So your car would have his for lunch the way it sits? I guess if it ran really well he wouldn't have started this thread, right? The magic word is "COMBINATION". The j head has much better potential, and he already has them, so build a good combination around them. You mentioned poor throttle response which reminded me of something. I wonder if the OP has locked out his distributor and is running the proper timing. That in itself could make a big impact on performance with low cylinder pressure.

And last, post all the 14 second time slips you want. I'll try not to get the vapors. Btw, I don't reinvent the wheel, I build great combinations. I wouldn't be surprised to see my suggestions put the car in the 12's if the chassis and tune were right. Again, as long as the motor isn't wore out.

The old school MP grind has 39deg of hydraulic intensity?

Using Mopars 85% formula, Yes. That is what Summit advertises as well. It would be nice to have one to measure for verification, though.

I'd be very surprised if it measured better than 50deg.

I'm not sure what checking height MP uses to determine their "advertised" duration numbers(and I've never seen it advertised anywhere), but it doesn't appear to be .006 tappet lift like several other cam grinders use.
As measured in a motor, the SB "292" cam was 305deg @.006.
I came up with 250.5@.050, which puts the (actual) intensity at 54.5deg.
And, supposedly the 284 and 292 cams had better intensity than the smaller grinds.

I have seen 318 cars running 11's, not what the guy is asking for.

Dwayne, I wouldn't be a bit surprised if those numbers were inaccurate, but at this point, that's all we have to go by. An apples to apples comparison would be too much to ask of MP, I guess. If the lobes are slower than that, it makes it even worse. I'd really like to see some numbers at .200" to eliminate the ramps and see how quick (or slow) the lobes are above .050".

In a low compression 318 that had a roughly 185@.050" stock cam, going to the 220 range is a pretty big jump. Like you said, it would need a lot of gear and a lot of converter.

You're right, I suppose a 13 second combination that overachieves would be a bad thing. I guess I'll sign up for unemployment this morning.

To shed some light on how far off the MP 85% rule can be.....

Looking at the 2007 MP catalog, they show cam # p4452782 as the "factory original" replacement cam, and that it has .429/.444 lift and 228/235 duration @.050.
The factory replacement cam is actually 210/220@.050........ But if you take their "advertised" numbers(268/276) and apply the 85% theory you get 228/235.

I have to believe that the MP "performance" hyd grinds(not the OE replacements) are all based on the same math.
As such, they should all have the same intensity.
The problem with using the 85% theory is that as the duration gets shorter, the intensity "looks" better.
The smallest MP hyd cam is 248/256, which shows a hyd intensity of 37deg, while the 320/320 shows 48deg, the 292 shows 44, the 284 shows 43, etc.

The MP cams are known as being smooth and stable grinds, not cams that have noticeably quicker intensity rates than the newest, fastest .904 stuff available from companies that make their living from cam design.

I guess what I'm getting at is, while I agree there are likely better cams for this application than the MP 260/268 cam, I seriously doubt it's really "too big" for this combo to run 13's.
If I had to choose between buying a new cam and lifters or milling the heads for more compression........ I'd take the compression.

A few years back I had Comp do some fast rate .904 lobes for me, based off the XE/HL .904 designs. The intake lobe is 265@.006, 221@.050(44deg intensity), .505 lift with a 1.5

I know the MP cams aren't accurate to the 85% factor, but it's really the only info we have to work with. It could be smaller, or larger. Who knows without actual measurements.

I don't disagree with your logic on the cam vs. compression. We agree that the cylinder pressure needs to increase, and milling the heads would do that but it might take a pretty good cut to get up to where the slow cam isn't softening the bottom end, and pull hard across a broad range. That's why I suggested helping things with a cam swap, and the 1.6 rockers. Not the only way, but will get the best results IMO.


I don't expect the OP to run out spend a bunch of money at once. I think he would be better served to make incremental changes and see what the results are. Then he has a good idea how beneficial each change was. Within a year, he could be deep into the 13s, and the bugs can be worked out at each change, instead of dealing with them all at once. That's just what my approach would be if it were my money.

Nice to know we can run 13's with a V8 Mopar engine and not need NITROUS. Lmao.

My first step would be a cranking compression test, followed by measuring the cam that's in the motor now to see how it looks in an apples to apples comparison to some of the more popular choices.......so I really knew where I was at with it.

If the cranking compression test yielded better than expected results(say, 130-135+), then I'd go right for the headers and converter.