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D2B2 Racing Performance 1987-1993 Dodge - Shadow

Best set up for SCCA ProSolo

I have a 1993 Dodge Shadow ES that I used to AutoCross with. It has made appearances at places such as Summit Point, WV (as a reply to a yahoo groups challenge). I was wondering is there any way to increase the rear camber on it to help it corner a little better?


Sure. Just increase the camber shim pack at the lower stub-axle mounting holes. You can buy the OE shims, but many of the aftermarket ones are plastic, better if you just cut them out of scrap aluminum.

If you have rear discs, you may also need to shim the caliper mount to keep the caliper centered on the rotor.

I spent MANY happy laps at Summit Point, MANY in a tweaked Turbo II Lancer Shelby.


over 1 year ago
ERIC's Car info Performance 1967-1989 Dodge

Correct 4 bbl manifold for a 71 Challenger Conv. 318 ci


I have a 71 Challenger Conv. with a 318 engine 2 bbl carb and I was looking to upgrade it to a 4 bbl carb. I was looking online at different manifolds and there seems to be a variety of different products. Is it possible for you to recommend one and why it would be better(trying to learn). Thank you

Eric Williams


I’ll assume when you mean ‘correct’, you mean from a performance aspect — there were no factory 318 4-Bbl cars in the early 1970s.

Later in the ‘70s and ’80s, there were 318 (LA wedge) factory 318-4 engines, but they ALL used 360 heads, which have larger ports. If you use a 340/360 manifold, there would be some port mismatch, which isn’t the end of the world, I’d not hesitate to bolt one on. Even and OEM iron casting.

Alternately, try to find a used aluminum 318 (or 66-up 273) manifold, they were made, back in the day, by both Edelbrock and Offenhauser.


almost 2 years ago
Smitty's C Performance 1968-1971 Chrysler

68 to 71 Chrysler Ignition Systems

Is the OEM ignition system from Chrysler has good as MSD and other ignition system sold today?


Will conversion to electronic ignition buy you anything? If you are talking pure performance, nothing whatsoever. The rule of thumb: if there is no misfiring now, you can swap to an ‘arc welder’ ignition system and gain nothing.

The gains from breakerless systems are mostly related to maintenance reduction (down to near zero) and timing accuracy and consistency. Breaker point systems start deteriorating from day one.

The ’72-up Chrysler EM electronic systems were good, although the mag trigger design was not quite as consistent, or as good in low temperatures, as later Hall-effect triggers.


almost 2 years ago
Rooker Racing Performance 1957-1974 Chrysler

8 3/4 hog head

I have an 8 3/4 rear end with the 742 casting. I am wondering what is involved in changing to the bigger one. I think it’s a 784? Do I need to change the axles, u-joint, gear carrier? I want to run a LSD differential but don’t know what kind of modifications if any that I would need to make. If it’s just swap out the hog head and everything is interchangeable that would be great. What am I looking at with this swap?


The “742” IS the big one!

You can just change the diff in your current pig to any style LSD you wish: Clutch-type (drag racer’s favorite), Cone-type (constant bias, great for snow/ice), or a TrueTrac TorSen (all gears, no friction materials, smooth as silk).

Or change the entire pig to one that already has LSD. All that’s required is re-setting the wheel bearing endplay.

There are two sized of companion flanges (yokes): Small (7260) and larger (7290). Swapping yoke is easy, there are also “crossover” (conversion) U-joints.


almost 2 years ago
Rooker Racing Performance 1968-1975 Plymouth - Road Runner


I have a 74 Roadrunner That will have ET Streets. I want to do a little street driving but also take her the Drag Strip every now and then. My question is about the rear end. Currently I have 2. I have a posi 8 1/4 with 4.10 gears and a 8 3/4 with the smaller hog head number with 3.23 gears. I want to run an LSD. I don’t know if the 8 1/4 will handle the 440. The engine currently has 13 to 1 compression but will come down per your recommendation earlier this summer. I have found some Dana rears with 8 lug shafts. Don’t know if I need to go that route. What do you suggest for street use and an occasional pass at the strip?


There’s no question that the 8-1/4" will expire quickly with sticky tires and a 440, esp. in a heavy car. The small-pinion 8-3/4" is also not great.

Your choices come down to:

> An 8-3/4" with the larger pinion bearings and shaft, i.e., 489 or 742 casting number.
> A stock 71-up B-body Dana 60, hard to find and expensive
> A “new” Dana 60, such as the Strange Engineering S60.
> Or, the dark hose, my personal favorite: A ’71-up B-body (not wagon) 9-1/4". These are cheap, very easy to work on, and very strong.

A truck Dana 60 can be cut, the 8-lug axles discarded, narrowed, etc., but the downside is that they have no provision for axle windup limiters (slang: “pinion snubber”).


over 2 years ago
B5 Blue Performance 1958-1978 Plymouth

Lazy Roadrunner- continued

Hi Rick, thanks for your suggestions on waking up my ‘68 Roadrunner. We did a footbrake test of the torque converter the car started trying to move at 2200 RPM, I am suspicious of the stock tach to checked it with a digital which seems to record about 16% less making the stall more like 2000.
Checked compression one cylinder at 130, one at 145 rest at 135/140.
You mentioned checking the phasing without disassembly as per the FSM? My 1968 Plymouth Service Manual doesn’t seem to cover that. The car runs , idles and drives great no overheating ect. It just seems to run too well for the cam to be out. My only issues are lack of low end grunt, lack of vacuum and poor gas mileage about 12-13 mpg. I’m wondering if we have to pull the front off the engine to check the phasing maybe I should have a new, closer to stock, cam ready to stuff in it.


Like so many dyno shops, they begin their pull at way too high an RPM to be of any use in diagnosing this problem, but I will tell you that: Whatever carb was on there is pig fat. PIG.

The problem, beyond the carb (which, being so rich, can certainly kill any crisp throttle response) the problem could be “too much” cam, although the dyno sheet doesn’t point to that, cam misphased (see p. 9-54 of the 1968 Plymouth FSM), or simply a bad torque converter, which I am now leaning towards.

Gear vendors results in some pretty strange U-joint angles and I’ve never been a fan of the way it is cantilevered out in space.


over 2 years ago
hemi dayz Performance 1968-1971 Plymouth - Barracuda

Lead additive

I recently purchased a 70 cuda with a 426 (about 550 HP) and was wondering if you recomend a lead substitute. I normally run ethynol free 91 octane in my 440-6 and that runds good. Would that work for the hemi or should I add a lead substitute? The car will just be a cruiser and will not be on trips over 50 miles. I’ve heard pros and cons about a lead substitute but since I don’t have much info on the motor i thought I would ask.


No production 1G or 2G Hemis had hardened exhaust valve seats; Chrysler began induction-hardening exhaust valve seats midway though the 1972 model year, this was the only engineering change to accommodate unleaded fuel. Today, many engine rebuilders add hardened seats (press-in) during head work on pre-’73 engines. Yours may have these already.

If not, some guys run additives, but my experience has been that, unless the engine is subjected to nearly continuous WOT operation (road racing, towing, salt flats, etc.), exhaust valve seat recession has turned out to be virtually a non-problem.

Bottom line: Relax, just drive — and enjoy — your Hemi’Cuda.


over 2 years ago
Outer Space Plymouth Performance 1966-1967 Plymouth - Belvedere

Satellite vs. GTX

Mr. Ehrenberg-

I have a 1966 Satellite 2-door hardtop. I have cloned the exterior to look like a ’67 GTX. The car currently has a 383. What, exactly, was different about the GTX, suspension and powertrain?

David Berkman


We’ll start with the engine, and assume you are referring to the 440 Super Commando (not Hemi) The ’67 engine was one-year-only, having unique pistons, heads (915), carb (AFB), and manifolds. Later 440s were similar, but not the same. It was internally balanced, con rods and crankshaft were drop-forgings. Oil pan was 4-quart, unbaffled, and a “sandwich” type windage tray was fitted. A one-year-only dual-snorkel air cleaner was used, with a silkscreened-aluminum “440 Super Commando” nameplate (“pie tin”). The engine was painted turquoise, valve covers were chromium-plated.

Automatics used a Chrysler-Indy built aluminum single-point distributor, 4-speeds had the Prestolite ball-bearing-braker, iron-case dual point sparker. Ignition wires were hypalon insulated.

A standard fuel pump and pushrod (same as 383) and 5/16" fuel line was used, there was no vapor return line.

Automatics used a beefed (4-pinion planetaries, etc.) A727, 4-speeds used the “Hemi” (18-spline) A833. Automatics use an 8-3/4" rear axle (3.23:1) while 4-speeds were 3.54-cogged Dana 60s (9-3/4" ring gear)

Exhaust was 2-1/2" headpipes with “H” crossover, dual reverse-flow mufflers, bright angled exhaust tips which doubled as the tail pipe hangers.

Brakes were 11" HD drums, front discs (Bendix, 4-piston) were optional.

Suspension (and shocks) were HD, with special biased rear leafs designed for windup torque control. A front sway bar was standard.


about 3 years ago
Best Damn Garage in Babylon Performance 1957-1957 Plymouth - Fury

Heads – Up Pistons – Down

Hi Rick,

I missed an important item – is a 1957 Plymouth Fury 318 (Poly) – Dual Quads.

As a recap – I measured the compression thickness of a set of NOS head gaskets (1618 722) that I picked up from Brad’s NOS Parts, and they compressed to 0.025".

However I do not know the Fury engine combination of combustion chamber volume and piston volume that gives the 9.25:1 CR. I really don’t want to fudge it – I want this engine to be completely blueprinted to 1957 Fury 318 specifications but use the most modern parts and machine work that are available today.

It’s been eight months of searching for this data and Jeffrey Diamond said that on this engine you are the go to guy. I want to CC the chambers to the factory Fury specification.


My documentation for the 318 Poly only goes back to 1960, and the guy who would know for sure is in a nursing home with Alzheimer’s.

My best guess would be:

> Pistons 0.003" above deck
> Heads 66.5 CC

My earlier advice re: not shaving the head (or deck) stands. If this were my engine, I’d measure the head volume, deck height, rod length, stroke, etc., then order forged pistons to give the desired C.R.

The other possibility is to find a machine shop blueprint/dimension book from the early ’60s.


over 3 years ago
Best Damn Garage in Babylon Performance 1956-1989 Plymouth - Fury

Heads – UP; Pistons – Down

In order to get 9.25:1 CR – What is the combustion chamber volume on a Fury 318?


You’d need to give me at least a few hints – poly or wedge? If wedge in the late ’70 – 1989, 2 or 4-Bbl? Or swapped to a 318 Magnum engine? (Great idea, BTW). And a head casting number would be nice.

The common early/mid-’70s 318 blueprint specs (for 9.2:1) were piston 0.056: in the hole (below the deck), head gasket 0.032", and the #2843675 open chamber head at 61.5 CC.

If your CR is significantly below this, a piston swap is the only correct fix. Head gasket sealing was already enough of a problem with the 4-screws-per-hole setup.

Another great swap are ‘89-’92 360 heads (#308), total bolt-on, big HP boost.


over 3 years ago
Project Roxanne Performance 1962-1974 Dodge - Coronet

Tubular Upper A-Arms

In a recent MA you mentioned you feeling about tubular A-arms. I was thinking about Hotchkis and now I’m feeling concerned. Do you have an alternative recommendation to achieve better handling? Thanks, Duane


What Hotchkis does is swap brake anti-dive for a slightly improved camber curve. Does this result in “better handling”? Maybe, kinda, sort of. Without getting overly wordy, let me just say that I am not a fan of this modification, mainly because having almost no anti-dive can cause the suspension to bottom under the right (wrong?) conditions, and a bottomed suspension has an infinite spring rate, which equals massive understeer – the car will simply not turn. Hello tire wall, Armco barrier, tree, etc.

That upper bracket add-on kinda worries me, too. I don’t know if there was any durability testing done.

I’m also not a fan of heim joints, not at all. At least in this configuration, when they fail you won’t lose steering or a wheel.

If you want tubular uppers, I’d go with the ones from Firm Feel. They move the upper ball joint rearward enough so you can have plenty of caster and camber, and use a bulletproof stock-type upper bush.


over 3 years ago
James' Junkers Performance 1971-2002 Dodge

Best smallblock heads?

I am building a 360 for street use (iron heads). This is on a tight budget! Which heads do you recommend?




360 heads can be broken down into two major categories, LA (1971-‘92) and Magnum (’93-up). There’s a certain amount of interchangeability between the families, but enough stuff must change to make the switch that, for the purposes of this Q&A, we’ll consider them as different animals.

Since you mentioned “budget”, I’ll assume we’re talking street use.

The best LA heads (i.e., 1971-‘92) are unquestionably the #308 casting (’88-92). For all intents and purposes, they are identical to the vaunted “X” castings with two major upgrades:

> The exhaust side is far superior – virtually the equal of the W-2 race head.

> They have hardened intake seats

Now, if, instead, we’re talkin’ Magnum (‘93-02 360) the OEM heads are all the same, and all flow like gangbusters with virtually no work. The problem is that any you’re likely to find will have cracked exhaust seats. They usually don’t leak water until somewhere over 200K+, but few guys want to swap cracked heads ON to a buildup. The solution are the inexpensive EQ (EngineQuest) heads, which make crazy power. I recently bolted a set of stock-valve-size EQs on a junkyard 360 and made over 470 HP, and now EQ is selling them with 2.02" valves!

They are also available with the LA intake bolt pattern, which is what I used.


over 3 years ago
Twisted Monkey Garage Performance 1976-1963 Dodge - Dart

How to give a 225 cid slant six more power

I am trying to keep my original 225 Slant Six in my 67 dart GT convertible, but it’s all stock, and I just blew the head gasket (which is one of many problems). Anyway, I am putting a more solid 225 in the car that will take much less work. However, I would like to keep my original 225 coming out of the car, and build a respectable street car motor out of it. I am thinking of putting a 4bbl on it, but have heard that that takes a lot of extra work compared to a two bbl swap. I’m just looking for suggestions that you think would let a 1967 225 slant put out more horsepower and torque that no one would expect from a 225. Thanks for your input, it is very much appreciated!


The slant six responds well to normal hop-ups, however, before delving too deeply into this, be sure you understand that most mods that increase the power output also require more RPM. Torque X RPM = HP!

A junkyard 2-Bbl swap is surely the easiest place to start, but a 4-BBl swap isn’t all that much more difficult. The best 2-Bbl manifold, however, as well as the current-best 4-Bbl, come from down under:

To make any real power, you need either a split exhaust manifold setup (Dutra), or headers.

A mild cam, some head work, and shaving the head at least 0.060", and you’ll be good to go. How good? That depends. The junkyard 2-Bbl bolt-on might pick you up 10HP, the full boogie 4-bbl, hot cam, header, head porting deal might gain 75 or more.

Have fun!


over 3 years ago
Girraffe Performance 1967-1969 Plymouth - Barracuda

Best wheel and tire size for drag radials on A body Barracuda

I want to get drag radials for track use on my 1967 Barracuda. I have two related questions.
Can I safely use the current fornt radial tires with a rear pair of drag radials?
What is your recommendation for rear wheel size and offset as well as tire size to maximize performance without creating clearance problems or other road driving safety issues?


Yes, in fact, drag radials were conceived for exactly the situation and useage you present. They’ll be fine.

8" wide wheels, with zero offset, present no problems, in 15", 16", or 17" diameter. 9" width also clears but things start to get cozy.

Section widths of 225mm are fine, 245 will also clear, but also gets pretty tight. I have seen 255 work but it is too close my comfort in my view.

Overall diameter should not go much over 25" if you’ll be using full suspension travel (cornering, loads, potholes).

I’m assuming that you’re using a stock-width axle housing and 4.5" bolt circle axles.


over 3 years ago
Dudes Restorations Performance 1964-1969 Plymouth - Barracuda

Engine Upgrade

Richard, I have a 66 Barricuda with a 273-2bbl. How hard is it to make it a 340? Are the valves the same in the 273-318-340? I just bought a refurbished 4-bbl stock intake manifold and a Carter 650 carb. Would they increase the horsepower or do I have to put in a cam? Its so nice to have someone with your expearience to go to for answers.Thank you for your time. I do have a lot of questions/


The basic valve and valvetrain geometry is nearly identical in all LA engines, this family included all 273s, 340s, ‘71-’92 360s, and ‘67-’91 318s; however, generally speaking, as the displacement and HP levels increased, the cylinder head castings had increased flow in lockstep. The “best” production cylinder heads for LA engines are considered to be the early 340 castings (“X” and “J”), and the ’89-92 360 (308 casting). These require a bore notch to use on a 273.

As far as “making it [your 273] a 340”, that’s out of the question, for a whole host of reasons. For a large power increase, the sensible swap is a ‘93-’02 360. It is amazingly easy to make almost 500HP from these engines without spending much $$$, and it is a very easy swap. Very.

Bolting on a 4-Bbl induction setup will make a noticeable difference, but realize that the factory 273-4 had high compression pistons, a more radical camshaft and springs, and a low-restriction exhaust system.


over 3 years ago

What causes my ignition system to cut out?

My electronic ignition keeps cutting out. What causes this? Too much heat?


First, the purpose of the small hole is to permit the ozone buildup (from the arcing inside) to escape, not for cooling. Later-design caps have a shrouded vent for that purpose. But that’s not your problem.

Next, let’s get back to some basic electricity. Voltage doesn’t “go” anywhere. It’s a potential. Thinking of it this way may help: If you hook up a garden hose to the fitting on the side of your house, attach a nozzle – closed – to the other end of the hose, and open the valve on the house, no water flows, even though there’s full city water pressure in the hose (and at the nozzle). That’s voltage! Now, open the nozzle – and lots of water pours out, even though the pressure at the nozzle is much lower now. That’s current, measured in amperes. How much total water flows out is roughly analogous to power (watts), Which, you can see, will vary depending on both the voltage (pressure) and the diameter of the pipe and/or nozzle throttling restricting the flow (resistance [ohms]).

OK, back to the Challenge®! With the engine idling, running normally, the coil positive side will usually have about 8 to 9 volts present. This varies due to several factors: battery voltage, coil resistance, ballast resistance and temperature, and RPM. Anything from about 7 to 11 volts could be considered normal, at least to the extent of: “that’s not your problem”. Consistently high supply voltage, however, can fry ECUs and coils, and is usually caused by a wiring error (jumped ballast),

If you swapped distributors, that would seem to eliminate the pickup (mag trigger) coil as being a trouble source. Of course, nobody says that you can’t have two bad ones in a row! Of course, be sure that the pickup gap is correctly set (0.006 – 0.008" w/ brass feeler gauge)

That leaves just 3 areas: Bad ECU, bad wiring/ballast/ignition switch, or bad ignition coil. You seem to have covered the first few areas (exc. the ballast!), but the “misfiring” you describe tends to point to the coil, I’d try a new one first.


over 3 years ago
Randy's Rumblers Performance 1960-1989 Plymouth

Overheating: Does turning on the heater help?

I have had two big-block Mopars with 22 inch radiators that were marginal on cooling. Someone recently told me that if I had turned on the heater, it would have cooled down the engine. Is that true?

- Randy


In general, yes.

Some Mopars of the muscle era had heater water-control valves, others had water always flowing through the heater core (with a “blend air” door to shut off the flow of air over the core). Either way, the heater core had a BTU removal capacity of close to 10% of that of the radiator, so, if you could stand the heat, it definitely worked. In fact, Detroit engineers are planning on tapping that capacity on upcoming models to reduce the size of the underhood cooling components. They’ll be arranged to blow the heat outside, probably under the car, in times of cooling system stress.

Still, I should mention that, in general, if your cars didn’t actually boil over, there was nothing to worry about — a hotter-running engine is actually more efficient, and the hotter the coolant, the more efficient the cooling system becomes. At 16PSi, a typical antifreeze mix won’t boil until 260 degrees plus — so there’s plenty of safety margin. Most new cars are equipped with 195 to 203 def. F. thermostats, and I use 195 in all new builds.


over 3 years ago
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