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.