That is the extra big bore big bore with the overlapping pistons!!

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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

That's the new upgrade for "overdrive", its called a "driveover rear end". Lucky it did not end up in a giant ball of punctured fuel tank induced flames.

First saw this Hypo Dart drop it draws on Gas Monkey demolition theater...

Beer assistant, hey beer assistant, where that guy go?

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Typo!

Try 3.445 bore!

DI, you know I run 215R75-14 street radials on 4.10's behind an a904 with 2500 stall.

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Part of Tyrde-Browne Racing

LOL... been a while since I had seen it on the street... it was that lapse of CRS you get when you're older...

Wow, thank you to Dart270, Ceej, Rick, ProCycle, and even DusterIdiot to a degree (yes, eventually I do want the turbo ). That is exactly the type of advice I was looking for!

To everybody else that chose to tear me down by assuming everything I said in my first post is serious or purposely ignored some parts in order to try to make me sound like a complete idiot... not so helpful. If you are a boring Human-being who likes things quiet or simple in your life, this is probably not the thread for you. I like a little excitement in my life, I work hard to afford what I have (I come from a poor immigrant family), and I mod my cars for me, not for others.

Dan, were you having a bad day or something? You kept making references to the car not driving well... how so? Too much heat/wear-and-tear? Too noisy (for your tastes)? Jumps a little too much due to the throttle being too hard to feather and the transmission shifting too firmly? Needs additional frame reinforcement? I'm sorry, but I'm looking for facts... like what the stated Cuda was doing with the mods it had that proved to be unstreetable in your opinion.

I also don't want a V8, because if I wanted to put one in, it would already be in there. The guy who sold me the car had a 318 and 340 lying around, and I can get 360's all day long... that was not the point of me being on slantsix.org.

For $7K there is a shop down the street that would stick a 400+hp LS1 motor and 6-speed in there... I don't want to do that because A.) not a Mopar, and B.) basically what every other person on the street has in their car, C.) is not a Slant Six with a stock forged crank which can accomplish everything that some people have been able to accomplish.

I know I overloaded my first post with questions/random information/attempt at humor, but here is my ultimate goal:

NA Slant that can run between 12.5 and 13 seconds in the quarter (ballpark give or take 0.5 seconds), but can technically run on the street with some vibration at idle... I don't want an incremental cam that barely does anything, as that truly would be a waste of money to me.

Yes, I meant .050" off the block AND the head for a total of 0.100" to make sure both surfaces are as flat as possible, I was planing to make-up the difference to that 10.1 compression with either pistons OR taking a few hundredths off from either the head or block based on the builder's advice when the time comes. The reason I want 10:1 or somewhere around there is to get the maximum power on premium pump gas instead of race fuel.

To get to my goals I'm building a 904, new differential, lighter/better disc brakes all around, electric fans, electronic ignition, modified and or lighted driveshaft, new lighter wheels, and lightening the car with fiberglass everywhere I can. The 904 is much lighter transmission than a 727 with a LOT less parasitic drag, and I'm not going OD, so the tallest gear I can realistically run is 3:55, but I may change my mind and get a different ratio rear later... there are lots of differential gear kits for the Ford 8.8"... starting with a rear that has at least some capacity to run on the highway.

There are also plenty of guys with big V8 engines running over 800hp with their V8-based 904's... I'm putting the guts of a V8 904 into my /6 904 and then replacing all bands, clutches, springs, valvebody, drums, planetaries, etc. with race-grade components reinforced with Kevlar where available. I have a separate thread to discuss the transmission build, no need to get into all of that here... I'm building the thing once to handle the 250-300hp build, and the later 450+hp turbo build. The stall of the torque converter will be a large part of what makes it driveable, so I'm starting low on purpose for the NA build.

I am not trying to build a "tow" motor with a ton of torque at low RPM, I am trying to spin the engine faster to build horsepower at over 5K RPM. I'm also cutting weight so that the torque becomes less relevant... not that my 72 Duster even weighs that much to begin with.

I don't drink and drive, so nobody has to hold my beer for me.

The cam WILL be swapped later for the turbo build. In order to decrease static compression I will do a combination of switching pistons and adding a very thick copper head gasket... that's one easy way of doing that, from what I know. Regardless, I'm not really looking for turbo advice just quite yet.

The 500cfm carb is what I have on the stockish motor and was purchased as a base for my engine upgrades, and as "pig rich" (inefficiently) as it runs, it easily added 30-40hp with my other mods and now at least stays up with a Prius and can pass Civics on highways.

Given some time and after tuning the 500 CFM carb with the built motor, I will eventually go to EFI as the next step before even thinking of turbo-charging the thing. Either way, will run wideband sensor to tune the AFR to where it needs to be with whatever carb or EFI I plan to run.

After the NA build is done, at that point I will have a larger stall (and smaller diameter) torque converter built to my cam specs. The 2500 RPM converter is an improvement over the 1700 RPM stock unit, and it is low on purpose to be able to work with my stockish motor with an extra 30 or so horses in a NEWly rebuilt transmission (why would I put my old tired unit back in?), while at least being drive-able with the new built motor... I like driving cars, not towing them everywhere. I also prefer to compromise on mods and do incremental increases to keep the car drive-able to be able to track the performance changes (have you tried searching for what impact some of these mods have on our cars?.. there is very little info).

Guys, all joking aside, please save your lectures. I don't text and drive, drink while driving, speed through neighborhoods, weave through traffic (especially without a turn signal), I let people through if they use their turn signals, and my mods also include bigger brakes, better seat belts, an extra mirror, and suspension. Most of the work to the motor and rear end will be done by a veteran hotrod/engine builder with at least 20 years of experience.

Tires going in back with 3:55 gears: Cooper Cobra GT 255/60R15 radials.

COMPLETELY OFF TOPIC AN IRRELEVANT: The 2005 CL65 AMG that is currently broken is broken because of it being a Mercedes... it needs both ignition coil packs and voltage regulator along with a new ABC suspension... it had nothing to do with what I did or did not do to it, other than maybe not driving it enough. The speed governor was removed by Renntech for speed competitions, and tuned by Speedriven, which allowed me to be able to hit 201 in a 1/4 mile from a 55 mph roll. All mods to the Benz were done by the prior owner. The Duster is meant to be fun to drive, like my '94 NSX. If I need another car to drive long distances (I live and work near home and drive less than 5K miles a year), then I can always use the unemployed Girlfriend's Range Rover or the C300 Mercedes I maintain for my early-retired Mother, which she does not even drive for many months at a time while she travels. It's not all about the money, either. I would simply enjoy pulling-up next to a V8 muscle car or a semi-quick modern performance car and be able to hang-in-there from a street light. Cut me some slack here, I'm not that bad of a guy.

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1972 Plymouth Duster:
- 225ci
- Offy 4-Barrel Intake
- Weber 38/38 DGES
- Clifford headers
- Split 2.25" dual exhaust
- Pertronix digital ignition conversion
- Black-out custom digital gauges
- Front disc brake conversion
- Viper Blue

Nope. Thanks for asking, though.
That's not what it sounds like to me, but that's fine. It's your car and your money and time; I'll leave you to it.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Some things in my post were clearly subjective, but it is factual when somebody likes or dislikes something, as long as it is specific.

For example: it is your opinion that I don't belong on the road, but it's a fact that you think that. lol

If a cam with some of the specs I've been asking for feedback on produce so much shaking that your eye glasses fall off at every street light, that would be something material to me... I wear sunglasses during the day.

If my fuel economy dips under 10mpg while still only producing 250 or so HP, that would be material to me.

If no matter how careful I am shifting 1-2 or even leaving it in full auto and it still chirps the tires and lurches forward at every single stop, that would me material to me.

If I'm not able to provide constant voltage to my sound system and AC, that would be material to me... then again, that's what batteries and capacitors are for, no?

Is my engine going to last more than a year and 5K miles with my build? That is material to me, as I don't intend to rebuild my motor every year. I'm rough on my drive-trains, so getting the most heavy-duty and correctly-built drive-train is important.

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1972 Plymouth Duster:
- 225ci
- Offy 4-Barrel Intake
- Weber 38/38 DGES
- Clifford headers
- Split 2.25" dual exhaust
- Pertronix digital ignition conversion
- Black-out custom digital gauges
- Front disc brake conversion
- Viper Blue

There is one more thing you could consider? If you want decent mileage with a somewhat radical engine, you really need to consider an OD. Since there are very few good options for the Slant 6 in a performance clutch and PP, you may consider a OD automatic. Not the Chrysler OD but the GM one with the adapter kit. Lou has one in his turbo car and my son has one for in his Duster. They are well supported and can handle some pretty big power. Just another option. It isn't cheap, but if you figure how much you will have in a good 904 and will still not have OD, it may look a little more affordable.

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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

A streetable automatic N/A Slant that runs 12.5/13.0 will be only slightly easier to find than a silver unicorn eating a rainbow and farting glitter.

Seymour has the baddest true N/A Slant streetcar on the planet. Follow his lead and make your car very, very light and put a stick in it.


Or, do like I did and build an overweight 14 second auto car and spray it to 12.0s.

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Official Cookie and Mater Tormentor.

I'll definitely check into that... I've also seen a company that make split-gear transmissions, which could be interesting.

The 904 for the time being is really only being used to have the least possible parasitic drag to drop the ET's a little, even at the expense of gas mileage. I don't see myself needing to take this thing over 80 mph ever, other than down the quarter mile, and I don't think it would be quite as peppy to run on the street or strip with a beefier OD transmission.

Realistically, this is something I would consider doing with the turbo setup if/when I ever get around to doing it, considering the extra power of the turbo would likely more than compensate for the powertrain loss of the NA build.

Not totally related to you, Rick, but let's also assume my head is getting the bigger valves (in fact 1.7/1.44 Engine Builder/SI Valves), my car already has a bigger aluminum radiator, a large electric fan, electronic ignition, a full set of poly urethane suspension bushings, and aftermarket 4-wheel disc brake kit well above OEM specs of my current drums.

Trust me folks, I'm not just trying to stick the largest cam into a motor and be done with it. Shaving the 0.100" off the block and head (combined) is a base line to get to the 10.1 compression and also depends on the pistons I will ultimately buy (I don't have those yet). All of the measuring for clearances will finally be left to the engine builder, but just wanted to have a good starting point with the cam choice, which is the main purpose of this thread.

I definitely want the engine to be able to spin above 6K RPM's and intend to get all parts needed to make that happen. The Comp Cams unit is a Mechanical Flat Tappet, Adv. Duration 264/264, Lift .440/.440, so thinking something more radical than that if I want to squeeze the last few horses out of the engine to get to my 250+ goal. I believe most people running a similar cam with bigger bore and such are generally capping-out near 250, I could be wrong.

No, this build will not be cheap and I am very well aware of that fact. My primary goal is to have a fun car for the street that feels a bit like a race car and can run something between mid 12's and 13's in the 1/4 after I put the car on a diet. It has no other purpose than to be fun. It will never be taken on long road trips, either.

Just wanted to provide some additional clarity to my initial post.

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1972 Plymouth Duster:
- 225ci
- Offy 4-Barrel Intake
- Weber 38/38 DGES
- Clifford headers
- Split 2.25" dual exhaust
- Pertronix digital ignition conversion
- Black-out custom digital gauges
- Front disc brake conversion
- Viper Blue

I'm thinking fiber glass hood, trunk, bumpers, fenders, lighter front seats, aftermarket heater instead of the heavy box unit, rear seat delete, dry cell car battery in the trunk, and well... the car already does not have much more than that in it, short of A/C which is needed in Texas.

Probably would need to talk to the hotroder to see where he thinks a hole saw could go.

The displacement and cam are going to be a big part of what could potentially make the difference on the speed portion... hence why I'm here.

Also, the Ford 8.8" is quite a bit lighter than the 8.75" from Mopar (not to mention a fraction of the cost) to help with the weight issue... really hoping that is the only non-Mopar part I use with this thing.

Lastly, I am not ruling-out nitrous, but hoping to not have to rely on it too much to get to my numbers.

At the end of the day, all things considered, and with what I already have for the car or planning to get, the cam choice is going to determine my final attainable speed/time on the track, so my goals would definitely move based on what I can and can not live with.

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1972 Plymouth Duster:
- 225ci
- Offy 4-Barrel Intake
- Weber 38/38 DGES
- Clifford headers
- Split 2.25" dual exhaust
- Pertronix digital ignition conversion
- Black-out custom digital gauges
- Front disc brake conversion
- Viper Blue

"short of A/C which is needed in Texas" Must have missed that, the plot thickens.

If you are wanting to buzz it over 6k routinely, you might be happier with a 170 over a 225.

It needs A/C, a rudimentary heating system... possibly a plug-in, and a basic 4-speaker sound system. That's right, all of maybe 70 lbs total weight to make the drives bearable year-round if needed.

The A/C is already converted and blows cold, still doing research on the heater, and the sound system is a simple 200 watt Alpine Bluetooth unit with 4 speakers I got last Black Friday for around $100 shipped.

So hence, this thread is for a semi-street-able car. It won't be completely stripped and live at the track. Why in the world do we have to choose just one thing for the car to do if it can reasonably well do everything I need it to do?

My budget it immaterial as I spend a lot of time researching things and getting things with pretty good value. I don't do "the best," I do what gives me the best bang for buck on a specific project, which excludes me stuffing an LS1 under the hood.

The Duster entered my life after I got tired of spending $3K-5K per trip to the mechanic (not even the dealer) with a certain German car I was not even equipped well enough to work on myself... then it got hailed on but somehow was not considered a total loss (screwed by the insurance company), and now I just rather put that repair money into the Duster until I get around to fixing the Benz and sell.

The cost of the Duster was $4,500 in rough shape + repair money from German car = fun and clean Duster that may be slower, but more of an experience to drive as the car will not have assists to do everything for me. I don't think I'm being unreasonable or too brag-y here.
I get that a 225 is not as "peppy" as its smaller brother, but unless I'm missing something, it's also just a smaller 225 with a different stroke... and it makes way less power at the top end of the RPM spectrum compared to the 225 at most parts of the spectrum. I admit, I'm a bit ignorant to 170's, however I also don't really feel like swapping the original 225 out of this thing. If I'm doing swaps, I might as well go for a V8, right?

I will not be constantly running it over 6K, but I want the thing to be able to hit 7K so that I could rev limit it to 6-6.6K and be able to drive it normally at whatever RPM the transmission takes it to in traffic OR to 6-6.6K if I mesh it at the track. I'm thinking of this engine as a diesel, however while the base line RPM of the stock motor is low, I do not know of another way to make an NA motor make more power other than to spin it, and I definitely know some of you do.... looking at Lou here.

I fully understand I will need stronger connecting rods, pistons, and push rods, and the whole thing needs to be balanced.

_________________
1972 Plymouth Duster:
- 225ci
- Offy 4-Barrel Intake
- Weber 38/38 DGES
- Clifford headers
- Split 2.25" dual exhaust
- Pertronix digital ignition conversion
- Black-out custom digital gauges
- Front disc brake conversion
- Viper Blue