OK, I'm dumb, need help

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Anyone else notice the last two six pics are of the Aussie inline Hemi six? I am curious if you have seen what it would take to adapt a tremec behind a \six and if you were looking at a new turnkey setup or adapting a used one over. If it were me, and I was building a truck with \6, I would look for a used Lakewood slant six bellhousing and a used Richmond Gear/Doug Nash 4+1 5 speed. Summit carries the individual gears to set up a progressive close ratio transmission. With that transmission, I would use 3.73 final drive gears, for give or take 2600 rpm at 65 with 31 inch tires. I would also plan on a hydraulic throwout bearing for the sake of simplicity. I am guessing you've already got a coilover 8-3/4? If not, then I would stay with the factory 8-3/8 (AKA 8-1/4) or 9-1/4 axle if you are staying with the factory width. Either one is more efficient and consumes less power than the 8-3/4, and you won't break either one of them behind the \6. I am guilty of towing a lot of things I shouldn't have with an 8-3/8 +NP435+ \6 '73 D100 and never had any problems out of it. On any crush sleeve pinion axle, it is advisable to use the Ratech crush sleeve eliminator. I wouldn't go through the hassle of coilovers either, I would fabricate spring and hanger mounts to use a Cal-Trac Mopar B Body kit, and even that's probably overkill for this combination. I would really be considering looking into a turbocharger build, I really think that's going to give the best performance for investment, and you've got a lot of room underhood to work with.
 
Appreciate the discussion. Much of what I'm thinking about hasn't been done before, and is why I have opened this thread. Maybe I'm just crazy. I like the modern Tremec. With it I get a lower 1st gear and an overdrive. This means I can run a numerically lower rear axle ratio (like 3.23 or lower) without sacrificing acceleration, and at the same time easy cruising on the freeway. At this point, my understanding is that my belhousing can be modified to accept the Tremec. Weld-in kits for front suspension and rear coil-overs are currently not available, so was assuming that these could be modified for my application. My new concern from this thread is wether or not I can put enough clutch behind this combo. Thanks for the input.
 
What year is your truck and how is it presently outfitted? You could get the great big iron anchor HD slant six bellhousing that came in front of the NP435 transmission, it uses an 11 inch clutch. Also a small block flywheel only needs one hole drilled in it to make it usable on a \6, a lot of slant six racers do this for an SFI flywheel, which is a must for any performance build.
 
Hey, this is new to me! If I can make a small block flywheel work, what belhousing is needed? This will be a 10" clutch? What about starter location? Thanks.
 
The factory used adapters in early a100s to mount a small block 727 to a slant six. The iron HD 11 inch \6 bellhousing would work, but I would contact Wilcap, they could pattern something up for you to be able to use a modern "catch-can" blow proof bellhousing to a tremec. They used to have one to adapt \6 to chevy V8 bolt pattern, this could get you into a used SFI bellhousing for a lot cheaper than a Chryco specific SFI bellhousing. I would be willing to bet the GM type Tremec would be cheaper than the Mopar specific one, too.
 
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Consider that more horsepower requires more cubes, more rpm, or more airflow With a given engine size, you only have rpm and airflow to work with. Since the slanty is severely limited in the airflow department;
about the only way a normally aspirated slanty can make significant power is to rev it. So consider how much higher you want to/can, rev it, then select the cam accordingly. That will give you an idea of it's power potential. Everything else you do to her will be to support that cam, so that it can get close to it's potential. And then you will have to match the new higher resulting powerband to the vehicle, with different gears, and a looser TC.
In the end you will have a lot of money tied up in what? Something like maybe an increase of 45hp at 5000rpm. How much does your loaded vehicle weigh? 3600 pounds? That comes to an increase of; 45/3600=.0122hp per pound........ and now the power peak is at ~5000 instead of 4000 . If you started with 125 hp, now you have decreased your loading from 3600/125=28.8 pounds per hp to 3600/170=21.18 pounds per hp. Hallelujah. Ok I get that you want to be different, to be unique, but maybe there's a reason almost nobody hops up a slanty for duty in a heavy vehicle.
Now in a lightweight-A, you might get 2800/170=16.47pds /hp...... but you started at 2800/125=22.4 about the same as the 3600/170=21.18pds per hp, from above.
If you want to have some real exciting street fun. I recommend 8 to 8.5 pounds per hp.
If you just want to relive your youth with like the memory of a 340Swinger, 10pds per hp
If you just want to squawk the tires now and then 13 will do it.
IDK what 21.18 will do for you, but ....... I don't see a line-up begging for a ride.

Ok but how about super charging? See now we're thinking. It takes about 7 psi to double your power, and I heard the slanty will take 10 to 15 or more psi. Lets pick 12psi. So that's like (12/7x125) +125= 339hp. Lessee that comes to 3600/339=10.62 pounds per hp, right in the fun zone.
And you can leave whatever gear ratio that's in there alone. And you don't need 5 gears anymore. The A833 will take anything you can dish to it. And if you wanted to, you could even run the A833od. (Or a stout 904 with V8 guts.)
But if a manual, then you are gonna need a V8 clutch and a V8 rearend,with a SureGrip, and some serious traction control. But since you now already have 2/3rds of the V8 stuff............. just how unique are you?
you could get similar results with waaaaaaaaaaay less money spent just by adding a couple more cylinders.
Jus trying to help, not ragging on the reliable as a stone-axe, six.
 
If you really want to do something different, I myself haven’t seen any D100-D150 third gen hemi conversions yet... With some of the heads and intake options available (as well as the $$$ aluminum MP block), it would definitely be different.
 
Theres sites i have seen that talk about how to port one, and which head castings are best for performance, as well as limitations based on runner design because of pushrod location. Every little bit helps.

The problem with the 225 slant stems from the earlier design. Before the 225 was thought up chrysler had the 170 , and 190 slants. It was closer to a square engine. Small bore short throw crank. These were small inch but rev happy for a 6. Being that the bore spacing was already set, machining tooling was aleady on the assembly line, and the need to come up with a bigger engine popped up. Chrysler raised the deck height, and designed a different crank to go in the new block. This resulted in the same small bores with a longer stroke. Not the best in terms of performance.

My recommendation is to find either a 170, or a 190 slant, figure out which head to run. I believe slanty heads can be milled safely to .100", .120" to bring up the compression. In this case you will have to lop off about 1/8" of the bottom of all the head bolts so they dont bottom out before they torque the head down tightly.

I had a 69 dart slanty i did a head gasket job for somebody years ago. Took .100" off the head to get the warp out of it. Ended up cutting 1/8" off the ends of all the head bolts so they wouldent bottom out.

I could be wrong with some of my recommendations, however i am not wrong on the head milling and headbolts.
The pushrods are on the opposite side of the head..........................
The slanty port has a very good coeffecient of discharge for it's size when ported correctly,....the problem is finding someone to do it near You that can be trusted to......
The real "it won't make as much" has absolutely nothing to do with the head, it has to do with the 225 ci of displacement....which is why We should all go out and scrap our 'teeners, 383's etc.......and buy 528 crate motors and screw all this "bitty motor" bullsh*t.
Most guys'd be thrilled sh*tless if their 440's pumped out 587HP, which is the equivalent of a 300HP 225, but Yeah, it could use a better head.........................
 
Thats all well and good, but i do prefer the gutteral roar of an uncorked V8 to the buzzin half dozen.
 
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Been a Mopar nut all my life but have never really paid much attention to /6. Am considering a performance build of a /6. Have looked at the Clifford complete setup and am impressed but I would like to know what more is out there. Is more performance available? Can it be stroked? How about more cam? compression? Is better ignition available w/o a plastic drive gear? How far could a person go? Thanks for the input.

C'mon guys we're in their forum.....
Slanties and turbos were meant for eachother.

The normally aspirated slanty could do OK ,too,
you know,
on something around 1200 pounds ;
Or even up to 2000 pounds if you hop it up.
but not at over 3000
 
Turbo slanty, now that i could get into. Read an article somewhere where a guy used a junkyard Garett T3 from a mopar 2.2 engine on a stock slanty. Heck if you go turbo you dont even need anymore than 8.0 to 1 static compression.
 
If a 5 speed O/D is what you want, just use the slant 6 4 speed bellhousing and a Passon 5 speed setup. Bolts right up to stock bellhousing
 
If planning on coil over four link on a truck, then your into pro street categoriy anyway. Usually, some sort of stroker or hemi with a tunnel ram or blower is the norm just because of the general weight of trucks. If you want to go fast with a slant six in a truck, the ‘80-92 D100 or 150 ram becomes a better option with its lighter thinner gauge sheet metal. Up to 87 if you want to keep the stock frame, as they went to the 239 odd fire six (318 less two cylinders). Go with manual steering, the factory truck/van box is fine. Saves a lot of weight over the great iron anchor power box, frees up power for the driveline, too. Dodge Dakota plastic tank aluminum radiator or the like for more weight reduction. Replace the side and back glass with Lexan. If I was going to run coilover rears, I would replace the frame from the forward cab mounts back on the frame with rectangular chromoly tubing to the forward bed mounts, and then go to round chromoly tubing on back. Even if taking NHRA specs and increasing gauge and tube size by a “streetable safety” factor of 50%, the weight reduction would still be worth it. Want to get even more weight off of “old porky”? Check out U.S. Body source. Fiberglass body components in any form and rating imaginable...
 
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A 300hp slanty with a 5 speed; that ought to be a blast, lol.
But I have an intense dislike for the sound of the BOV.
Ima thinking more along the lines of an automatic, and 2.76 gears; power with economy,cruising at 65= 2250, and 60@5300 in first gear, badaboom

Now about your little traction problem.................. lol
 
Vroooom pshttttt vroooooom pshttttt vroooom pshtttt. Whats wrong with that? Used to use a first gen DSM BOV on my turbo 2.2s thought it sounded cool when it would dump pressure every shift.
 
Greetings again AJ! My mind is a little (actually a lot) slow right now, I take it BOV is blow off valve for the turbo? It surprises me no one has made a muffler for those yet, but the import crowd generally likes to annoy people so the majority of the market wouldn’t buy one anyway. I guess if you can’t go fast for a whole summer without breaking something, or your car slows down 2-1/2 seconds because you take your girlfriend down the strip (seen it in person, Honda Power!) you have to make up for it somehow...
 
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I thought my early combo was pretty powerful. At 106 in the Qtr that's around 350 hp. But one day some friends piled in, totaling 5 of us, and the skinniest was me at 200. So the extra 800plus pounds was easy to feel, even in 10.97 starter gear. I kept it low key,lol. That combo was 3650, so about 10.4 pounds per horsepower. Adding 800 put it at 12.7. It kindof felt like an early teener. Not long after, I took the rear seat out,and it's never been back in.

If I had deeper pockets, and if I thought the World was gonna be here for longer than I do, I would for sure turbo something;
I think an old thick-wall teener. I have a 69 here I think could make a good foundation; or maybe one of these 340s under the bench. Or heck, I even got a 65- 273 in the shed. Yeah Ima thinking 273@ 400 should make some torque, and with 3.23s and overdrive I should be able to squeak some serious mpgs out of her. But then I recall that 367HO currently under the hood,Hyup I could detune that a fair bit, and then the turbo could kick it back up a few notches.
Hmmmmmmmmmmmmmm, decisions decisions.
But the slanty is staying in the Volare,lol.
 
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Friend of mine has a Dart 4 dr sdn. Slant six, FI, turbo, 200R4 trans. Drives it all over the country, including to the drag strip. Runs mid 12's in the 1/4 mile, and mid 20's MPG. Granted not a low buck project, but he did most everything, himself, except for the trans build, and conversion parts.
 
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