318 build problems & new direction

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cudaracer

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So I have posted in here several times seeking what to do with my stage II build, to mostly correct my stage I mistakes.

Stage I Build included,
-Top end rebuild on stock bottom end 72 318 with 904 auto, shift kit and 3.23 gears.
-Top end included 308 cast 360 heads (decked 20 thou), 0.028" head gasket, DP Weiand, eddie 600, dakota 360 log manifolds (love these btw) and a comp cam XE268h.

My complaints mostly had to do with no bottom end. Explained mostly due to lowered CR after decking at about 8-8.2, stock torque converter and the wrong automatic cam with a sweet spot at 1600-5500 ( especially since I never rev it past about 3500 rpms).

So now I have selected the following to correct and improve my situation, and thoughts and experiences would be greatly appreciated, as I also intend to write a lengthy piece about my experiences once done.

Stage II Build,
- since this is really a fix, as I am on a budget, I should really call this Stage Ia, but nonethelss, I am adding proform roller rockers (only $244 at summit) and the whiplash 318 cam.

The cam fits my automatic cruising drive style perfectly, with an idle - 4200 sweet spot and the Intake Valve Closing angle of only 30 deg ABDC, explains how they keep the dynamic CR so high with my stock CR. The comp cam was 60 deg by the way, explaining how I lost so much DCR as a result.

So with that cam sweet spot, regaining dynamic CR and roller adj rockers, I should see a significant gain to the pig I currently have.
Any thoughts on where I should be with hp and torque? I will have tested btw, so taking bets;)

Thanks.
 
I was also wondering why nobody lists IVO, IVC, EVO, EVC on their cam specs. Hughes does, as I was spec'n out my cam using the IVC number to keep a higer DCR, to work with my low static CR.
 
cudaracer said:
So I have posted in here several times seeking what to do with my stage II build, to mostly correct my stage I mistakes.

Stage I Build included,
-Top end rebuild on stock bottom end 72 318 with 904 auto, shift kit and 3.23 gears.
-Top end included 308 cast 360 heads (decked 20 thou), 0.028" head gasket, DP Weiand, eddie 600, dakota 360 log manifolds (love these btw) and a comp cam XE268h.

My complaints mostly had to do with no bottom end. Explained mostly due to lowered CR after decking at about 8-8.2, stock torque converter and the wrong automatic cam with a sweet spot at 1600-5500 ( especially since I never rev it past about 3500 rpms).
Click to expand...

My build is quite similar with the exception of the heads, I stuck with the stock teen heads. I think my 318 performs exceptionally well for what it is. I also run headers with dual 2.5 inch exhaust. Running the manifolds "might" be holding you back, I don't know.

Also timing, have you ironed that out?
 
I have no idea where my timing is as factory markings stop at 10 on both sides. I put tape on there, but it flung off like right away, even after cleaning it good.

I would guess about 18-20 advanced.
 
Try putting paint marks on the damper and timing tabs. I use white paint or white out.

Put the engine at TDC and mark the damper at TDC. Then put a mark at 10° on the damper. then rotate the engine 10° and make another mark for 20°, then another mark at 30° and repeat as you wish/need....


Paint won't fly off like tape....
 
A 1" or taller 4 hole carb spacer will help your bottom end also if you have the room.
 
I have my 318 at like 35°. I'm curious to follow this thread as I've never heard of a small block build for low end torque? Well I guess for the street? To pass cars in traffic on the way to work and stuff. 3500rpm's?
Truth be told, I do like to stir the pot a little. With that said - about 4 grand is where the fun starts with my 318! !! I'd say - don't be afraid to wind that thing up a bit! !
 
mguner said:
A 1" or taller 4 hole carb spacer will help your bottom end also if you have the room.
Click to expand...

That might help some, but timing first. If it isn't timed correctly or coming in quick enough it will feel lazy down low.
 
j par said:
I have my 318 at like 35°. I'm curious to follow this thread as I've never heard of a small block build for low end torque? Well I guess for the street? To pass cars in traffic on the way to work and stuff. 3500rpm's?
Truth be told, I do like to stir the pot a little. With that said - about 4 grand is where the fun starts with my 318! !! I'd say - don't be afraid to wind that thing up a bit! !
Click to expand...

I have an automatic setup for firm shifting at cruising speeds. It shifts firm into 2nd at about 2800-3K, then about 3K into 3rd or about 75mph. Taking her to 3800 puts me at about 110mph. I have little use for anything past that and don't really know how to rev it any higher.

And no I am not changing gears.
I see no reason why that 318 can't get nice torque right from idle and I bet I will be knocking on the door of 400 ftlbs peak.

That makes far more sense for an automatic, and it reminds me of the words of one of the best builders I have ever met......who said, build it for low end torque and don't care or look back at hp numbers.
 
Forgot to mention,
part of the reason I am leaving the bottom end alone (aside from cost, time and effort during cruise season), is that with only 84K babied miles and no smoke blowing, I makes little sense to tear into it based on the gains I seek.

And why is Hughes the only one who sets up a cam to work so well with low CR engines and aggressive lift.
 
Yes get a cam in there which will build some cyl psi & Dave Hughes is the man. Set the initial with the "vac gauge method" then with that initial timing number in hand shorten the slots to get 35 total (initial+slots) with vac can capped. then play with springs starting with tossing the 1 heavy spring with the elongated loop on one end & sub in a mr gasket or MP light spring along with keeping the OE light spring. You want the lightest spring combo that will keep you just under the pinging point at WOT up thru the gears on your hottest/driest (most likely to ping) day AND you want the curve to start no less than 200 RPM above your in gear idle speed which is what you will see at the stoplight then hookup the vac adv can & you want to stay just under the pinging point in everyday traffic under varying load (in hg) conditions and CW with a 3/32" allen wrench will make it come in sooner. The eng is an air pump & the most restricted part is generally the ex manifolds. I ain't sure if the ones you have are good ones or not. The best SB iron ex man combo is a 68-70 HP pass manifold and a 92-early 93 magnum dr side exhaust & the early magnum ones have an ~ 2& 1/4" if not larger outlet dia and the later ones have 1&7/8. quite a difference. jet the carb right & an innovate LM1 meter is the way to go hands down
 
Rapid Robert said:
Yes get a cam in there which will build some cyl psi & Dave Hughes is the man. Set the initial with the "vac gauge method" then with that initial timing number in hand shorten the slots to get 35 total (initial+slots) with vac can capped. then play with springs starting with tossing the 1 heavy spring with the elongated loop on one end & sub in a mr gasket or MP light spring along with keeping the OE light spring. You want the lightest spring combo that will keep you just under the pinging point at WOT up thru the gears on your hottest/driest (most likely to ping) day AND you want the curve to start no less than 200 RPM above your in gear idle speed which is what you will see at the stoplight then hookup the vac adv can & you want to stay just under the pinging point in everyday traffic under varying load (in hg) conditions and CW with a 3/32" allen wrench will make it come in sooner. The eng is an air pump & the most restricted part is generally the ex manifolds. I ain't sure if the ones you have are good ones or not. The best SB iron ex man combo is a 68-70 HP pass manifold and a 92-early 93 magnum dr side intake & the early magnum ones have an ~ 2& 1/4" if not larger outlet dia and the later ones have 1&7/8. quite a difference. jet the carb right & an innovate LM1 meter is the way to go hands down
Click to expand...

wow, awesome tips RR.
I will forward this to my builder, you all might know him on this forum as forced340
 
Thanks bro. My eddy 1406 600 was lean out of the box. A strip kit is a absolute neccessity. What is the idle vac? An Eddy can have a problem on an eng with low vac numbers with it's type of idle circuit
 
cudaracer said:
I have an automatic setup for firm shifting at cruising speeds. It shifts firm into 2nd at about 2800-3K, then about 3K into 3rd or about 75mph. Taking her to 3800 puts me at about 110mph. I have little use for anything past that and don't really know how to rev it any higher.

I'm a little confused. Are you saying that the transmission upshifts around 3k at wide open throttle? That shift point is too low for even a stock 2v 318. Have you tried shifting it manually? If you don't intend on ever taking the engine over 3800, you would probably be better off with a stock cam.
Click to expand...
 
good lift, short durations, valve timing that does not kill my CR.
That is my goal.

And nobody does it better, it seems, than a whiplash.
 
Hey everyone, been gone for while but back to planning for cuda.

I have thought about several scenarios for the 318 in the past, and I have FINALLY decided to go absolutely cheap as I only need to add pistons and block machining. So check out my latest plan, and feel free to guess at my expected power. Also, is my CR too high with that cam for 91 oct?

1. Using same 308 cast with 1.88/1.60 valves and mild porting in bowl and gasket matching
2. Bore to 3.97" same 3.31 stroke
3. KB167 pistons
4. CR = 10:1 with 0.020 gasket (65cc chamber)
5. Comp XE268 (268/280) hyd cam
4. DP Weiand 4 bbl
5. Eddie 650 carb
6. Magnum exh manifolds - ported
7. 2.5" dual exh with Thrush mufflers


So that is the setup I would like to add to a mild original 318 with about 87K miles.
What can I expect from the rods and crank, and should I modify those?

Thanks
 
If you are going to take it that far then new rod bolts and rods resized. Crank machined as necessary with new bearings, rods, mains and cam. Also I would recommend only boring as much as needed. .060 might be too much and make less power than .020 or .030 . I did this build with 302 heads no porting and shorty headers. No slouch for sure. Good luck.
 
Lelo Dart said:
If you are going to take it that far then new rod bolts and rods resized. Crank machined as necessary with new bearings, rods, mains and cam. Also I would recommend only boring as much as needed. .060 might be too much and make less power than .020 or .030 . I did this build with 302 heads no porting and shorty headers. No slouch for sure. Good luck.
Click to expand...

thanks, but, how is boring too much bad for power? I already have heads that are designed for 360 bore, so my hope was to add cubes and further unshroud those valves. What am I missing?

Also, what can I expect to pay for rod machining and bolts, because I can get brand new rods for about $250
 
It can make the cylinder walls too thin and they can actually flex losing power. Taking the bores all the way out is not always the best answer.
 
cudaracer said:
Hey everyone, been gone for while but back to planning for cuda.

I have thought about several scenarios for the 318 in the past, and I have FINALLY decided to go absolutely cheap as I only need to add pistons and block machining. So check out my latest plan, and feel free to guess at my expected power. Also, is my CR too high with that cam for 91 oct?

1. Using same 308 cast with 1.88/1.60 valves and mild porting in bowl and gasket matching
2. Bore to 3.97" same 3.31 stroke
3. KB167 pistons
4. CR = 10:1 with 0.020 gasket (65cc chamber)
5. Comp XE268 (268/280) hyd cam
4. DP Weiand 4 bbl
5. Eddie 650 carb
6. Magnum exh manifolds - ported
7. 2.5" dual exh with Thrush muffler

So that is the setup I would like to add to a mild original 318 with about 87K miles.
What can I expect from the rods and crank, and should I modify those?

Thanks
Click to expand...
Yours is similar to mine other than the heads and pistons...same CH piston but mine are 2618 forged and the heads are Indy 192/162...single plane eddy, holley 4150. Same comp cam.

Wouldn't idle right until I set the vacuum advance can up right, or to my liking anyway. got an adjustable vac can that is all in @ 10" of vacuum. Put a limiter on the vacuum advance arm that only allows 24* timing at idle. initial is 18* so the can is only giving 6* additional at idle. It's all in by 3100 at 40* and at 3200 cruise it's giving 46* total. had to do something...vacuum was too low in gear to idle below 900...that fixed it to a point...then I learned about T port sync, set that up correctly and made a huge difference in idle quality and exhaust stench.

After break in it went on the local chassis dyno. iirc it put 286 hp and 261 tq to the rear wheels. That's around 350/360 horse at the crank...the dyno tec said. It's a stout screamer and does come on HARD between 4500 and 6000.

I run 3.23's also, stepping up to 3.55's now and going 408 stroker. I love the screamin like a banshee thing but...Put a rev limiter on it. It'll spin up so fast when you break em loose you can hit 7grand easy. I did and now the motor is being assembled again after putting a new rod and piston in it. I hit 7 grand plus at 25 mph when I stomped on it. It broke em loose and over revved instantly and smoked a wrist pin...thought I had valve contact from float but the heads are fine...just got a new rod and piston to balance the same as the bad one. I'm finishing up putting the motor back in this weekend...it was a strong motor and will be again...but with a rev limiter. In a few months the 318 will need a new home...I don't regret the 318, I love it....just don't want to have to rev to 6 grand to get the power...therefore I go 408 this time.
 
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cudaracer said:
Hey everyone, been gone for while but back to planning for cuda.

I have thought about several scenarios for the 318 in the past, and I have FINALLY decided to go absolutely cheap as I only need to add pistons and block machining. So check out my latest plan, and feel free to guess at my expected power. Also, is my CR too high with that cam for 91 oct?

1. Using same 308 cast with 1.88/1.60 valves and mild porting in bowl and gasket matching
2. Bore to 3.97" same 3.31 stroke
3. KB167 pistons
4. CR = 10:1 with 0.020 gasket (65cc chamber)
5. Comp XE268 (268/280) hyd cam
4. DP Weiand 4 bbl
5. Eddie 650 carb
6. Magnum exh manifolds - ported
7. 2.5" dual exh with Thrush mufflers

So that is the setup I would like to add to a mild original 318 with about 87K miles.
What can I expect from the rods and crank, and should I modify those?
Click to expand...
Stock torque converter ;I never rev it past about 3500 rpms.
Click to expand...

Headers! That cam wants headers.Without 'em you will be sacrificing 10 to 20odd horsepower at the peak, and torque through out the rev range.
Your Scr looks to be 8.22@165psi, probably too high even for 91gas, depending on your squish dimension.With a smaller cam, 10/1 may be too much.
>I'm not a fan of the thin headgasket.I also question the use roller rockers and, the use of that cam if you never rev it past 3500; both overkill in a 3500 engine. At that rpm the 268* is just waking up, and you have sacrificed the stout bottom end that comes from installing the proper cam for your intended useage. Also that cam will not be happy without help from a hi-stall TC and 3.23s is the lower limit for it.
That cam does not have a 30* ICA, more like 60* in at 106
Even a 2bbl 240 cam has an ICA of around 50*

>Here's how to figure the ICA:
360 plus (intake duration divided by 2, less the installed centerline) less the intake duration, less 180, change sign on the calculator,equals ICA
Example 1; 360+(240/2,-110),-240,-180,signchange=50*, for a 240*/114
Example 2; 360+(268/2,-106),-268,-180,signchange=60*, for a 268*/110
Example 3; 360+(292/2,-104),-292,-180,signchange=70*, for a 292*/108

>You're confusing me. Why are you building a 6500 rpm engine, to spin it only to 3500 and saddling it with handicaps like a stock convertor and 3.23s and too much compression? This is all messed up.And why the pre-occupation with how much power will it make if you never explore that power?

Here's an idea;Try to evaluate what you really want.
Pick one only, from each line, and highlight it.
Low-rpm cruiser.Tire fryer.
One gear bomber.Zero-to-60 screamer.
Punch it at 32mph and light up the tires.
This is a DD,or weekend bomber, or street/strip,drag-racer,other?
I care about what gas I have to burn;................. not a bit,some,a lot.
Cruising at hiway speed in comfort means to me; not a bit,some,a lot
I care about fuel mileage;................................... not a bit, some ,a lot
Then I,for one, will come out of confusion,hopefully.
 
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