13's, stock '71 318 short block.

[alan627b]

You can reach the 13's and probably even the 12's with a stock type 318 bottom end, the 13's fairly easily. Just don't be disappointed if it doesn't get there right way. Most of the guys who have mostly stock engines that run well might spend a very long time trying lots of little tricks and using their heads to trim a hundredth or two as opposed to going broke spending big chunks of money to no good end.
Some of these guys who do, may own the same car for years to get where they are, and are usually the guys everybody respects for their tuning ability.

I saw a stock eleminator class 67 Coronet with a 318 2 barrel running very respectable times at our 1/8th mile track. All steel, Carter or Stomberg 2 barrel, and was only shifting it at 4800 rpm (!) and still turning times that would put a lot of 340 cars to shame. It can be done!
Alan

 

[rmchrgr]

Hey T67POWER, thanks for the well-thought out reply.

I'm confident I can get it done, really it's just a matter of choosing parts wisely. Desktop Dyno has helped narrow down the choices.

In my mind, ET has a lot to do with chassis set up so instead of spending a disproportionate of money on an engine build, the plan is to spend an equal amount on the chassis to get it to hook.

Keeping the stock block in the chassis just allows me to move on to the next step quicker.

 

[myfirstmopar]

has anyone heard of a 318 HP head

 

[moper]

I think if it was me, knowing that these are really place holders but possibly could be tweaked to feed a better engine easily... I'd look into RHS LA-Xs with the 1.92 intake. I know Hughes has them for $875/pr but you'll need to upgrade the springs. My reasoning would be the EQs or stock Magnums would not be enough in any form to feed a decent engine nor will they accept larger cams later. So I think overall those heads might be "the best fit", knwoing there will be changes relatively soon after I'd get the heads with more potential from the get-go. For a camshaft... You almost need to look at "claimer" type cams because you can't do too much lift with no valve relief. So I'd try to spend the coin on a set of rockers and run a solid lifter cam in it. Also, the heads are decent enough that you don't need the dual patern cam. Something like the Magnum 270S would be great in it. Keep the intake dual plane (Performer 340/360, Crosswind maybe?) and carb under 650cfm and I think a basic 4150 series DP would be fine. I'd also run a convertor in the 3K range. I think if the lower end is ok that combo should get you close to mid 13s in bad heat, low 13s after it's all debugged in good air.

 

[rmchrgr]

I think if it was me, knowing that these are really place holders but possibly could be tweaked to feed a better engine easily... I'd look into RHS LA-Xs with the 1.92 intake. I know Hughes has them for $875/pr but you'll need to upgrade the springs. My reasoning would be the EQs or stock Magnums would not be enough in any form to feed a decent engine nor will they accept larger cams later. So I think overall those heads might be "the best fit", knwoing there will be changes relatively soon after I'd get the heads with more potential from the get-go.

I agree, however... using Desktop Dyno and the flow #s from Hughes' webpage, I plugged both the Iron Rams and the Indy/RHS heads into several different combos. The Iron Rams were better EVERY single time, didn't matter what cam/intake etc. I'd actually rather not use the Magnum valvetrain with all it's inherent compromises. I'm leaning towards the Indys for the above reasons, would work well ported on a future 340.

For a camshaft... You almost need to look at "claimer" type cams because you can't do too much lift with no valve relief. So I'd try to spend the coin on a set of rockers and run a solid lifter cam in it. Also, the heads are decent enough that you don't need the dual patern cam. Something like the Magnum 270S would be great in it.

I have a set of NOS adjustable rocker arms, thought about using the MP .490 solid in it. Hughes has a small solid too but it's not so great IMO. Thought about one of the Lunati Voodoo cams too, (hyd) they seem a tad bit better than some of the other 268 cams out there.

Keep the intake dual plane (Performer 340/360, Crosswind maybe?) and carb under 650cfm and I think a basic 4150 series DP would be fine.

I have an LD4B, should work OK. Was thinking about a 750 cfm 3310/4160 carb with vacuum secondaries. Quick fuel has a cool kit for 4160 carbs, they can be tricked out pretty easily. Maybe a 650 DP would be good too, not sure yet. 4160s are slightly more street friendly.

I'd also run a convertor in the 3K range.

I research converters all the time. Seems a lot of guys run the Dynamic 9.5", but I'm thinking it may be too much for this combo. I have 4.10 gears and a low gear set for the trans, might allow me to run a higher stall.

I think if the lower end is ok that combo should get you close to mid 13s in bad heat, low 13s after it's all debugged in good air.

Car has like 60-something miles on it, not beat on or anything. Have yet to do a compression test. Probably won't at this point.

It's always hot and humid at E-Town.

 

[rumblefish360]

has anyone heard of a 318 HP head

Yes, the factory used the term loosely on there HP 318 4bbl. engines. It was a 360 head.

MoPar performance also sold 318 HP heads which were nothing more than OE heads with better valves back cut with a valve job.
They also sold "302" ported heads which were very good on high performance 318's. A better choice than a 360 head in most cases. Theres a time and a place for a 360 head on a 318.

 

[rumblefish360]

It may be hard to find the Pirple .490 cam. You could custom spec one out from Comp cams for pennies more.

I ran the LD4B and it was a good intake. The 750 cfm 4160 on top may be alot. Build dependent thing of course.

 

[Dago Red]

I think I've got a couple of .484 Purple Shafts floating around here someplace if you're interested. I have one in an 8:1 360 in a 3300# wagon and it goes mid/low 13's all day. Stock J heads and an Offy dual plane 360 intake, 1 5/8's headers, mufflers, pump gas, Holley DP. Been in the car for over a decade. Fish is right: that LD4B is a kick butt low compression intake.

 

[rmchrgr]

Done some more research into solid cams. Using Camquest, Comp recommends the XS268S for my application over the 270S. Plugged it into Desktop Dyno which says 355 hp with the RHS heads. Not too bad! Volumetric efficiency seems to suffer a little with a solid cam though. On paper the Voodoo 60403 still shows the best VE results with 96% @5,500.

In other news... have not been under the car recently but I will probably have to deal with a rear main seal leak before I start beating on it. Might replace the oil pump and pickup while the pan is off. When I have everything ready to go I'll address those things.

 

[MoparJoe20]

13.60's@101 1.77-1.80 60' In my old Duster - 318 shortblock with 262k, rings & bearings replaced, polished crank, windage tray and melling HV pump, Comp xe268 cam, 1.88 J heads with the bowls cleaned up, M1 single plane with 4777 650dp holley, headers & 2 1/2" duals Trans 998 non lockup, rebuilt, stock VB and MP 175k converter, Rear 8.75 with 3.91's & clutch sure grip, 275/50 drag radials.

Ths suspension was all stock, 6cyl leafs& T-bars, OE shocks, etc Body was stock except a lift off glass hood, still had a bench seat, battery up front etc, it also had centerlines, it weighed around 3100# wthout me in it.

 

[LXguy]

Best thread evar. Sounds like fun. I almost did this and still really wish I had.

Having a good hooking chassis can make a little horsepower go a long way. I had an (ahem) 5.0 Mustang. Bone stock throttle body to pan with some chassis improvements and lightening, went 12.90s with a 4.10 gear and slicks. Car still weighed 3200 pounds with me in it.

You're lucky on your shortblock. My '71 318 slugs were .110 in the hole. Combustion chambers were about 70cc also, but you'll alleviate at least that going with aftermarket heads. I would err on the side of small with the camshaft. Dynamic compression losses with a too-big cam will kill your horsepower. That camquest software is notoriously optimistic.

I'd highly recommend spending money on the converter. Done right, its really cheap ET $$$/tenth wise.

I'd go with a bigger carb if possible. My bone stock 318 was pretty well matched for a 670cfm Holley with that LD4B intake.

Oil control is a cheap place to pick up power. Windage tray and good oil pan (and good oil) are all worth ET.

My '71 Dart 318 car was 3150 approximately with bench seats, 50 lb air conditioning compressor, ridiculous heavy power steering, etc. I imagine you should be able to get it under 3000 pretty easy.

 

[rmchrgr]

Best thread evar. Sounds like fun. I almost did this and still really wish I had.

Hey, thanks for chiming in. I think it's a good plan. As said before, it will be the easiest way to get it down the track without spending a fortune. I just have to save up a little more green for the major components. Caltracs are close to a grand, heads are $900+, wheels and tires are several hundred and on and on. Even a 'budget build' is super expensive. I could buy cheaper stuff I suppose but these things will translate well for the future 340.

Having a good hooking chassis can make a little horsepower go a long way. I had an (ahem) 5.0 Mustang. Bone stock throttle body to pan with some chassis improvements and lightening, went 12.90s with a 4.10 gear and slicks. Car still weighed 3200 pounds with me in it.

Chassis is ET, horsepower is MPH AFAIK.

I've been interested in NHRA stockers for a while now, those guys really seem to understand how to maximize a factory-type chassis set-up with a comparatively limited amount of horsepower on tap. It's basically gears, good converter and Caltracs. I suppose that's the way any car could run no matter what the class though.

Steep gears on the street can be the toughest part, no one wants to drive on the highway with 4.56:1 gears. The low gear set in the 904 should help this combo, makes a more advantageous final drive ratio in first and second.

You're lucky on your shortblock. My '71 318 slugs were .110 in the hole. Combustion chambers were about 70cc also, but you'll alleviate at least that going with aftermarket heads. I would err on the side of small with the camshaft. Dynamic compression losses with a too-big cam will kill your horsepower. That camquest software is notoriously optimistic.

I've read in a few places that the '71 in particular had higher compression than some other years. Not sure about my own block though. I hoping it's no more than .060" down. I'll report on that when the heads come off.

In regards to the cam, I actually asked Comp for a suggestion and they said the XS268S would be good.

I'd highly recommend spending money on the converter. Done right, its really cheap ET $$$/tenth wise.

Custom converters are not cheap. Probably over a couple G in some cases. I'm hoping an off-the-shelf one will work OK, something under $500.

I'd go with a bigger carb if possible. My bone stock 318 was pretty well matched for a 670cfm Holley with that LD4B intake.

If I get the RHS heads I could run a 750. The intake runner is 179cc or something like that.

Oil control is a cheap place to pick up power. Windage tray and good oil pan (and good oil) are all worth ET.

Not sure I'd install a windage tray with the block still in the car. I've read in some places that it's not worth a whole lot and other sources say they are a must have. I'm on the fence about this one.

My '71 Dart 318 car was 3150 approximately with bench seats, 50 lb air conditioning compressor, ridiculous heavy power steering, etc. I imagine you should be able to get it under 3000 pretty easy.

On my NY registration card it says 2985 but I'm thinking that can't be right. Maybe without any fluids.

Either way, the diet has already begun - A/C system is out, heater box is out, radio is out. Thinking a fiberglass hood will help. Have lightweight Wilwood calipers from another project that never got used, an aluminum master cylinder and skinny front wheels. Converted to floor shift/manual steering. Aluminum intake (yours!) aluminum water pump, taking out the bench and putting my A100 van seats in yada yada yada. Shooting for 3,150 with me in it, I'm 170.

Whew, that's a lot of talk. Hope I can get this thing rolling soon, I'm crawling out of my skin thinking about it. Just have to wait for the money to come in. Sold my beloved magnesium wheels last year in hopes of using the cash for the Dart and ended up paying bills with the money instead - kills me to think about that.

Was thinking about asking for a raise at work soon, haven't destroyed anything lately...

 

[LXguy]

With a dual plane intake, you can run a pretty big vacuum secondary unit without worry.

Good luck with it, man. Call Lenny at Ultimate. I've got his custom T-brake, balloon plate converter in mine, cost about $850.00. He says the street stuff is right around $500 so I think he could help you out, and I know it would work better than a shelf converter.

Tell him Steve sent ya-LOL ;)

I wish I was closer. I'd love to help you out with this.

Steve