Real GM modules are on Rock Auto. I personally have never had any trouble with the cheap ones either. Running them on 4 vehicles for the last 6-8 years. No relays either. Maybe I am just lucky.

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

I hope you guys don't have me for lunch for saying this, but

The last 318 that I hopped up a bit, was in a 83 3/4 ton that I used the snot out of, and what I did woke it up quite noticeably for truck duty and yes the mileage was much improved as well.
It was originally a 2 bbl motor, and always ran good but more power never hurt in a truck.
I put a set of hooker super comp headers on it with true duals,(no, no cats) converted it to Magnum heads with the stud rockers at a stock for a Magnum 1.6 rockers, added a stock replacement 360-2bbl cam, (extremely close to identical to a COMP 252 small block cam) and topped it with a Carterbrock 625 carb on a standard Performer (not the RPM version) and had many that didn't believe it was still a stock 318 bottom end under those parts when they seen what I was towing with that truck. It had a 727 in it and 3.55 gears. I left those alone.

Similarly smaller combustion Chambers, slightly higher compression, a little more carb, and a little more cam would certainly not hurt a /6.

Since the thread has gone down the path of extreme emissions control, I might as well mention that my son and I have a dream to replace the Slant with an electric motor or hydrogen fuel cell or whatever is available years from now. With this build I'm just trying to get the Slant burning fuel as efficiently as it can while keeping things simple for my first time rebuilding a motor. I know it will still be a big polluter compared to a new car, but I hope it will be better than it has been.

Today's news is I picked up a 4-wheel 1000 lb rated engine stand at Harbor Freight for $48 with a coupon. I plan to borrow a hoist from a coworker, maybe next weekend. I think I have most of the tools I'll need other than that.

I also talked to one of the two machinists in my area today. I'll meet the other guy in a couple of weeks and decide who to go with. In the mean time I'll start pulling the engine as soon as I get the hoist.

I wouldn't go to "extreme emission control" extent. Just a basic rebuild, bringing all machine clearances back within tolerance, and a careful job of tweaking and tuning will help with power, performance and emissions. Clean up the block deck and head sealing surfaces, at least you don't have to worry about shaving the intake mount surfaces as you would with a V style engine. make sure carb is in good shape, throttle shaft bushed if needed and all adjustments made as they are supposed to be. Timing and carb adjustments need to be made as per engine needs and wants, ,may not exactly be by the tune up guide from back in the day. make sure distributor isn't worn out, and advance mechanism works freely without binding and that the vac advance can isn't blown.
Tweaks to advance curve welcomed. for mileage, max advance without detonation (again regardless of what the sticker may say, production tolerances plus 40 years of wear and tear means those sticker specs only make a good starting point) slightly more cam and a Super 6 setup would be my main deviations from stock... and keep a vacuum gauge handy, check it often.... especially after "break in".... the highest vacuum you can achieve and retain with whatever your setup may wind up as, brings smoothest running, best performance and mileage you can get out of "your" setup. along with lowest emissions youre gonna get.... remember... K.I.S.S. principle. no need to overcomplicate.


I don't worry about Prius style MPG numbers but I strive for the best I can get "out of what I have".... I clearly am not a fan of newer cars.... my newest is a 2001 (newest I have ever owned also) and some of IT's electronic crap drives me crazy let alone the newer crap I have to deal with at work.... its all fine as long as its working but when something isn't right, hair gets pulled out, tools get thrown towards the bench and wall, and yes sometimes problem vehicles get pushed aside...…

http://www.slantsix.org/forum/viewtopic ... 4&start=15 Is this your post? Plugs still look look like that?

Read your old posts, exhaust smell mentioned a lot ,even in traffic, smell after hot soak,fuel in oil. But runs good hot and Cold. Old float still in the carb. There were some old bulletins TSB that discuss things close to what you have there,pertain to holley 1945 carbs,high fuel level More testing needed before taking things apart.

Yes, that was my post. I appreciate you taking the time to help me troubleshoot. Replacing the spark plug wires and adjusting the choke solved those particular problems. I have rebuilt the carburetor, which was NOS 5 years ago and only has about 12k miles on it. I've adjusted the valves several times using the while-running method, and the last few times they were not far out of adjustment. I've adjusted the timing, checked vacuum advance, adjusted idle mixture, checked vacuum, etc. etc.

As you might have seen in my old posts, I had reasonably good results when I did a compression test (multiple times over a period of months, decent results each time). However, I've had 2 shops do a leak-down test and both reported significant leakdown on various cylinders. I've been pretty mystified as to how the good compression test can be consistent with the bad leakdown test.

I appreciate the advice to check more accessible things before tearing the engine apart. But (1) I've done a lot of that already, and (2) I actually want to tear the engine apart. Some folks spend their time and money on golf or travel, I am using mine to learn about engines.

I wonder if you can find a core motor to rebuid, and your car can be running the whole time you are learning and building...

Lou

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Home of Slant6-powered fun machines since 1988

Good thought, but I don't depend on my Dart for transportation and this time of year I often don't want to drive it anyway (they salt the roads if anyone mentions snow). Plus the block that's in there is stamped with the car's VIN, so I'd like to keep the same one, and I don't want to do multiple engine swaps.

In preparation for pulling the motor, I got everything disconnected except for the 2 upper engine to bell housing bolts. I was about to hook up my borrowed Harbor Freight 1-ton hoist to the block when I discovered its arm isn't long enough to reach the lift point. D'oh. All the Harbor Freights in my area are out of stock on the 2-ton hoist with the longer arm, and won't get deliveries until Friday. Is this what's meant by "taking it slow?"

I did try moving the hoist around to the passenger side of the car, but it still doesn't reach.

So for future reference for anyone that might be reading this, you'll need the 2-ton hoist with the extra 16 inches of boom length. Especially if your car is a later model Dart with pointy hood and big bumpers.

As I'm about to take my disassembled motor to the machine shop, I'm starting to think about cams and compression ratios. A few folks have recommended the RV-10RDP or 2106r grind. Oregon Cam can turn my old cam into a 2106r for $89, which seems quite reasonable.

The stock 1974 cam has these specs:
Open/Close: Intake 16/48, Exh 54/10 (Duration 244/244, Overlap 26, Lobe Sep 110)
Lift: Intake .406" Exh .414"

The RV-10RDP/2106r has:
Open/Close: Intake 19/55, Exh 55/19 (Duration 254/254, Overlap 38, Lobe Sep 108)
Lift: Intake .444" Exh .434"

If I understand correctly, the 2106 will give me a bit more torque at low RPM due to the higher lift and longer duration, but the idle may be less smooth. How will those effects combine with increased compression? What's a reasonably high but "safe" static compression ratio? By "safe" I mean not likely to be overly hard to tune on 87 octane.

Do I understand correctly that higher compression makes it harder to find the tuning sweet spot where idle is smooth and you don't get ping under load? Do I also understand correctly that this is why you would recurve the distributor, to get more initial timing with less total timing?

First you need to measure your TDC deck height from piston to block deck. That will help you plan your build properly. Also, you'll need to cc the head once they are done with valve work.

You are correct in your assumptions. That cam is not RDP (reverse dual pattern) since the duration is same on int and exh, however, it will work well. Also, please post the duration at 0.050" lift since that has more effect on running/tuning. I can't see you noticing a difference in idle between the stock cam and the 2106.

I would shoot for a true 8.5 - 8.8:1 static comp with that cam and to use 87 octane and not have difficult tuning.

Lou

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Home of Slant6-powered fun machines since 1988

2106 cam: 214/210 @ .050"
I don't have the 0.050" lift numbers for the stock cam to compare.

Deck height: between 0.152 and 0.161 for the most part. I measured front and rear of each piston using a straight edge across the deck and a digital caliper. #5 was the most extreme high and low with front 0.162" and rear 0.146". I don't stand by my measurements 100% because the deck was pretty uneven (following the bossed pattern of the OEM head gasket), the piston tops were a bit crudded up, the caliper probe is flexible, and I was never quite sure if the caliper was truly perpendicular to the deck.

OK, so the 0.050" numbers say it is RDP. That should work very well with mid-high 8s static comp.

I wonder if your block was decked (milled down) before? 0.150-0.160" is quite low for all the forged-crank engines I have measured. What year is the engine again? If that is right, you won't need to deck the block very much.

Lou

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Home of Slant6-powered fun machines since 1988

I don't think the engine has been taken apart before. Wasn't the factory spec 0.145 deck height? This is the numbers-matching 1974 block.