225 /6 at 250HP?

After 16 years she finally moved on her own.


My father gave me his '72 Dodge Dart Swinger Special when I was 2. Up until 1999 (when it was last running) he drove the car somewhat regularly until the front ball joints got bad and he didn't want to drive it around with me and my sisters in it. Fast forward to 2016 I got the car running and drove it 70 miles at about 70mph most of the time, with relatively no problems.

There's a whole story on that, but to stay on point. She drove great and has enough power to do what is needed... but as most I want more. What I really miss is my 1990 Mustang Vert. 5.0L (0-60 in under 7 and 14 some quarter mile) So basically that is my goal.

What would it take to make a reliable DD with about those kinds of numbers, while still being comfortable running 80 mph for hours at a time? (Basically I dont want to run 4.88 gears) I do want to turbo and go EFI for... well all the benefits of EFI. Budget, well I am cheap when I can be, as well as I can fabricate most of my own stuff and all the wiring and tuning the system would be something I really want to learn. But I understand certain thing cant be done cheap.

Just as a note I am currently attending Wyotech so I have decided to dedicate my life to mechanics in general. (Diesel, Gas, Turbo, N/A, Off-Road, Carb, EFI) I have already worked with most systems and am eager to learn the proper way on more. So learning a new system is actually a plus for me.

slant six will need help to get 250 horse ...At the very least a 4 barrel manifold or turbo......easier to put a 360 / 727 and a 3.23 gear should get you where you want to be...just use Shumacher coversion motor mounts from /6 to 360.....Lots of EFI companies out there for SBM....Or just go with a carb

turbo, fi, 2.73 gears and an overdrive transmission.

With the overdrive, you could use the lower ratio 1st gear (2.74:1) in the transmission. It would be quicker off the line to help out with that 2.73 gear.

I could do the v8 swap, but its so common and I understand why. But, if I go through the trouble of swapping to a different motor it is getting a modern EFI built engine with the transmission (maybe going to the extent of an AWD setup). My '72 Scout2 and '56 Willys Pickup are for the large V8's and high HP.

I would also like to try and get decent MPGs I know some who have turbo'd the slant six have gotten 30 mpg (not what I expect, but if it happens). I know my Mustang got 28 mpg even with the top down on the freeway at 80 mph. If I got 20 I would be happy (my father was getting 24 mpg the way it sits now).

Are you guys talking about the A883?

Edit; I did some more reading and found out that is a manual. I would like to stay auto though. There's plenty of reading for me to figure that out on my own though.

Keep in mind that the slant six is only 225 cubic inches. Doubling the stock HP puts you in the 1 HP/cu.in. range of 225 HP. Doubling your HP is never easy with any engine. To do that will take more cylinder pressure in the form of higher compression or turbo/supercharging. The most cost effective, in my opinion, is turbo charging. There is a lot of information around from others that have gone that route.

Congrats on wanting to further your technical education by going to Wyotech and kudos for wanting to upgrade the often over looked slant 6. I hear the same boring thing almost daily, why bother with my 318 when I can source out a 360 blah blah blah. Head over in yhe forums to the forced induction mopars tab and and at the top in the sticky's in turbo slants. Read up there and start to message the members on their setups. You'll find most members here are quite helpful in guiding new members to a descent combo that may reach your goals.

I just did a slant 6 build in my wife's cuda. Did the heads with 340 valves, did a cam upgrade, did headers, did intake, did electronic ignition, did a 4 barrel and did the dual exhaust. It probably makes 180 hp max.

I probably spent as much on it as a V8 swap. That being said, It runs great, pulls great on the road, gets 26 mpg and is different for sure. Probably wouldn't do it again though, as a stock small block would out perform this hopped up 6 any day.

The Slant Six.....we do it because it's difficult.

I also suggest turbo, for what you want.

I agree with badvert65. V8's will likely always be more cost effective to build for hot rodding. 250 Hp at flywheel is not impossible with a 225. But the more you "pump" up any engine, the more likely durability is going to decline. I think of the many 1.8 and 2.0L VW's I've seen running in the 9's in the quarter mile but grenade themselves every 10 passes unless rebuilt every 9 passes. An exaggeration but not by much. I love a hopped up slant but, if just starting out and on a limited budget, the V8 is more cost effective and doesn't have to be pumped up to the degree a six would to get to your stated goals of mid 14's and 0-60 times in the 6-7 sec. range.

momoparman said:

I just did a slant 6 build in my wife's cuda. Did the heads with 340 valves, did a cam upgrade, did headers, did intake, did electronic ignition, did a 4 barrel and did the dual exhaust. It probably makes 180 hp max.

I probably spent as much on it as a V8 swap. That being said, It runs great, pulls great on the road, gets 26 mpg and is different for sure. Probably wouldn't do it again though, as a stock small block would out perform this hopped up 6 any day.View attachment 1714949278

Click to expand...

Definitely wouldn't be getting 26mph though!

True.

I would add that MPG isn't really an issue for most rodders. Its SPM that matters. Smiles per mile.

No matter what you build, the goal is to get it out, drive it, and enjoy it!

I am not completely concerned with budget at this point, just figuring out what parts I need to start collecting at this point. If it takes me years to collect all the right parts and build the setup I would be fine with that. Right now I am happy enough with the power that I would not mind driving it daily. I would almost bet it is faster than my '96 Impreza that I am currently DD and would still get comparable MPG's to boot. (22-25mpg in the Impreza)

I already have done a GM 4pin Ignition Module swap. As well as the car already has a super six, so it's not a has to be done now kind of thing.

From what I have read it sounds like the 2.2L turbo pistons, 340 valves, Dizzy re-curve, Custom turbo exhaust, T3 turbo, and head porting should point me in the right direction.

I was Kinda wondering, is there any reason that I couldn't build a custom intake as well, using the same principles as the exhaust, just have to do a little more work for the Injector bungs, throttle plate and MAF?

When I get out of school I want to acquire a junk /6 and build a mock engine bay (or the front of a wrecked car) to do all the custom work so I can keep running mine until I'm ready to do the swap.
Is that an insane idea?

jollykreiger said:

I am not completely concerned with budget at this point, just figuring out what parts I need to start collecting at this point. If it takes me years to collect all the right parts and build the setup I would be fine with that. Right now I am happy enough with the power that I would not mind driving it daily. I would almost bet it is faster than my '96 Impreza that I am currently DD and would still get comparable MPG's to boot. (22-25mpg in the Impreza)

I already have done a GM 4pin Ignition Module swap. As well as the car already has a super six, so it's not a has to be done now kind of thing.

From what I have read it sounds like the 2.2L turbo pistons, 340 valves, Dizzy re-curve, Custom turbo exhaust, T3 turbo, and head porting should point me in the right direction.

I was Kinda wondering, is there any reason that I couldn't build a custom intake as well, using the same principles as the exhaust, just have to do a little more work for the Injector bungs, throttle plate and MAF?

When I get out of school I want to acquire a junk /6 and build a mock engine bay (or the front of a wrecked car) to do all the custom work so I can keep running mine until I'm ready to do the swap.
Is that an insane idea?

Click to expand...

This is a very interesting discussion with lots of possibilities... and, with several different ways to go. but, since it's YOUR car, you make all the decisions; I will offer what I think might work for you. The fact that you are only looking for a modeate amount of power (250 HP?) will make this a lot cheaper than if you wanted 450.... and, I will try to enumerate some pertinent facts along the way.

First off, the turbocharged slant six has some unique personality quirks, not the least of which is the strange final drive ratio gearing it seems to like best. Two guys (both FABO members) have turbo slant sixes that make a little over 500 horsepower each, and extensive testing has shown that they both run quicker and faster in the quarter-mile, with 2.76:1 gears. My own car, another turbo slant six, proved to show the same results.

So, you won't need an overdrive. You'll already have one. And, that negates the necessity for two ratios, one for the hiway and one for the strip... which means, you can install a cheap, plentiful, 8.25" unit out of a Dart, Duster, or Aspen/Volare (to replace your 7.25" weak, one-legger and be done with it.) Forever.

The 8.25" rears are getting expensive... and are just not necessary for this car.

The Buick V-6 that powers the Grand National has virtually the same engine size as your 225, so, that factory-installed turbo is the perfect size and, you might be lucky enough to find one used, online, or in a local junkyard.

The two-barrel Super Six manifold can be used to mount a Holley 350 or 500 CFM carb, with blow-thru mods, saving the cost and hassle of EFI.

The Pishta turbo-mount/ exhaust setup (pictured) is a cheap, easy way to handle the header problem. He (Pishta) is a FABO memeber too, and has lots of good advice. Just ask...

A water-injection unit (Snowperformance.com makes a good one) will negate the necessity for an intercooler.

This should be a pump-gas motor.

A stock, electronic ignition distributor hooked to an MSD Blaster coil, with an MSD 6-AL module (usually available on eBay, used) will handle the ignition with probably no problems.

Your stock cam and valvetrain should work fine for this. It will still idle like a stock motor.

You can run a manual transmission OR a 904 automatic with this setup, but, the manual-transmission clutches seem to be problematic in trying to deal with the gobs of torque these boosted engines make. My advice would be to run an automatic because turbos seem to like them...

Iskenderiam (the cam guy) rents an O-Ring cutter so you can cut your own O-Ring receiver grooves in the block and it is FOOLPROOF... I know that because ~I~ did it... successfully.

At this point, I should tell you that the nicest thing you could do for yourself is, buy a wideband, data-logging oxygen sensor (Air-Fuel) meter. This is an absolutely CRITICAL part of this build and will save you time and money. You simply cannot do this build without one. That should be in all capital lettters. I just learned that, for the first time, somebody is selling these A/F meters with the capability of measuring the exhaust of vehicles running on leaded fuel... Lead would always kill the O2 sensor in there units, before. $91.00.... Ask me how I know...

The cylinder head needs bigger valves, but the ports are OK, untouched with 1.74"/1.5" valves... They are on eBay, too, I think.

A stock converter and stock tranny should work fine...

You WILL have to buy a wastegate and a blow-off valve, and I would recommend buying a boost controller from Racin' Jason Kramer in Utah. He has a website. About $50.00, but, worth it.

Keep your Air-Fuel ratio about 11.5:1 at full throttle under boost, and you limit your igniton timing to 18 degrees. You will have to run a vacuum diaphragm to get better gas mileage, but it quits creating spark advance when it comes under boost, because the vacuum goes away.

With those settings, you should be abot to avoid detonation, entirely, and 93 octane should work well in yhay motor.

Make your redline 5,000 rpm.

This, with 12 pounds of boost, should give you the 250 horsepower you are looking for, and maybe a ittle more.

Wallace calculatirs says that amount of power should generate quarter mile times of about 13.90 at 97+ mph, if you can get it hooked up. That's in a car with a total weight of 3,400 pounds, including driver.

It's not easy; tuning the carb for an 11.5:1 mixture under coost is the hardest part. The A/F mewter makes it a lot easier...

I forgot the fuel system...

Stock pump with a boost-referencing line running from a fitting the top of the pump. to the intake manifold. This will raise your fuel pressure at the carb to 5 or 6 pound more than whatever the boost is, guaranteeing a suficient supply of fuel under boost.
Below is a picture of the Pishta-designed J-pipe (you'll have to build it, yourself.) And, some picture of my junk.

That is one beautiful setup.

Thank you for all that information.

So just to clarify a few things. I dont need to mess with the engine much (just larger valves).

But, it is crucial to get the AF correct to both get the most power and not lean out and burn valves.

So if I modified the Holley 2300 (500cfm) I have sitting on my Scout that would be an almost perfect carburetor to start with?

And the O ring cutter, that I am guessing is for the Oil cooling lines to and from the turbo?

jollykreiger said:

That is one beautiful setup.

Thank you for all that information.

So just to clarify a few things. I dont need to mess with the engine much (just larger valves).

But, it is crucial to get the AF correct to both get the most power and not lean out and burn valves.

So if I modified the Holley 2300 (500cfm) I have sitting on my Scout that would be an almost perfect carburetor to start with?

And the O ring cutter, that I am guessing is for the Oil cooling lines to and from the turbo?

Click to expand...

Yes, that is the perfect carburetor for this buildup. Perfect! Use the modifications described in "Hangar 18" website and monitor the A/F ratio with you new O-2 meter and you'll be fine. Holley sells a 2-box set of jets (all sizes) to enable that. Get a set...


The O-Rings are for cylinder-sealing and encircle the tops of the cylinders on top of the clock. See picture below...

O-Rings are common practice for forced induction motors because cylinder pressure under boost goes high enough that a standard head gasket won't contain it; it will blow out. The O-Rings form a high-pressure seal and prevent that. The cutter is pretty much fool-proof, so don't sweat doing it; the way the tool is designed, it's pretty much impossible to mess it up. They give you copper wire to fit into the groove. Cometic doesn't make a multi-layered-steel head-gasket for the slant six, so I used a Fel Pro gasket that has a fire ring around the cylinder. I centered the O-Ring on that fire ring (it's about an eighth of an inch wide, and it wasn't hard to do because the cutter is adjustable as to width.) There are two different-size cutters available; you'll need the smaller of the two.

Good luck! You're gonna LOVE the way that thing runs...

momoparman said:

I just did a slant 6 build in my wife's cuda. Did the heads with 340 valves, did a cam upgrade, did headers, did intake, did electronic ignition, did a 4 barrel and did the dual exhaust. It probably makes 180 hp max.

I probably spent as much on it as a V8 swap. That being said, It runs great, pulls great on the road, gets 26 mpg and is different for sure. Probably wouldn't do it again though, as a stock small block would out perform this hopped up 6 any day.View attachment 1714949278

Click to expand...

Man! that's nice.

Bill Dedman said:

Good luck! You're gonna LOVE the way that thing runs...View attachment 1714949479

Click to expand...

UM....
I just noticed what appears to be a bolt in the head of a piston. Whutt???

That bolt appears to be in the piston, but, it's not...

I machined a cylinder-size (less .010") piece if eighth-inch-thick aluminum to catch the shavings when I cut the O-Rings, so that when I was done cutting, I could just pull the aluminum piece out the top of the bore, and, the shavings would be lifted out, leaving a relatively-clean bore. Easy clean-up.... The (very short) bolt ran through the top of that aluminum disk and was just something to grasp with pliers, to lift the disk out.

That's about as "high-tech" as this engine gets... LOL!

My dad (who gets smarter in my memory as I get older,) once told me, "If there's a hard job, give it a lazy guy; he'll figure out the easiest way to do it."

I can't argue with what's been said, but I'd like to throw in another option.

To travel 80 mph for hours atta time and realize good fuel economy, and hit 14's is not rocket science. But the roads to get both are a bit at odds withe eachother.
The tricks for the former are relatively simple; light weight, low rpm, and small engine.
The tricks for the latter are just as simple; a favorable power to weight ratio.
The turbo is a very effective tool to make both happen.
If your pockets are deep and you have lots of time, then the turbo route will certainly get you there.
But your goals do not necessarily REQUIRE a turbo slanty
But in NA (normally aspirated) mode 14s are easy with 275 hp, and certainly possible with a tad less. So that means almost any 360 will get you there, even a LowCompression 2bbl 360 has the potential. It however will need some help. And a 3 speed automatic is not gonna do it.
To cruise at 80, comfortably requires an rpm of under 3000. To get favorable fuel mileage, the Rs will need to get down to 2000 or thereabouts.
So here are the final drive ratios(FD) to hit all the bases NA.
Quarter mile; With a junkyard 360 hoping to hit 90 at mid 14s you are gonna need to trap optimally at something like 5200, so 4.56FD will do it. You will want at least 3 gears to get you there.
80 mph cruise; to hit 2000 will require a 1.92FD ratio.
There are no current appropriate 4-speed autos that can turn a 4.68 into a 1.92, as this requires a .42 o/d ratio.So a compromise will be required. A .69 is available.
So now we need to bias things a bit.
No 1, the junkyard LC360 is out. You are gonna need more power to pull a lower gear to 90 mph and you are gonna need more efficiency to up the mpgs at a higher cruise rpm.
So what kindof ratios might be more appropriate?
Well with a .69 o/d, lets bias for mpgs and choose 2200 for a cruise rpm, and 27 inch tall tires(255/60-15). This will be 3.23s. So then it remains to build enough power to hit 90 with 3.23s. With a 360 as a base this is pretty easy. You just need the usual mods such as headers, a 4bbl and reasonably high compression. The stock 360 cam will maybe get you there. A 220ish fast-rate is almost guaranteed to break 100mph, and I built one that hit 106 with 3.55s and a 4speed.That's a PW of 10.8, so at Dart weight of 3350 say(car and driver), that is 310hp.(Did I mention it was easy?). (106 is actually in the twelves)

So there is your NA recipe; small high efficiency engine(360) with an O/D auto and 3.23 gears, plus light weight(3350)

It should be said that mid-14s could just as easily be achieved with a teener. Hitting 14.5 requires a pw of just .060. At 3350 pounds, this is 200 hp. The teener however is gonna need optimum gearing. It's not gonna do it with 3.23s. So you will have to bias the teener for the ET, and then your 80 mph targets will be compromised. Well the teener could do it, with a stroker kit.

So now what remains is cost and uniqueness, and time.
As to cost;
So sure the turbo slant can do it without the O/D. But the stock 7.25 is not gonna last long putting up with all that torque. So the slanty needs a rebuild with a hi-flo head, plus a complete rear and beefed up tranny, plus the turbo kit.
The NA kit is a Hi-Compression unported 360, with an O/D auto and the stock 7.25 will last a long time with nothing more than a good-working SG.
As to uniqueness,
yes the turbo slanty fits the bill.
As to time
Since you will be doing all the engineering on the Turbo kit, Things take time. A lot of time. And one day the thought will enter your mind;"sheit if I would put a V-8 in this thing, I coulda been driving it 2 summers ago"

See the V8/904 route is quick and easy, and the combo can be fine-tuned as you go.Even with 2.76s out back, the V8 will motor along nicely doing a reasonable job in stock form.That gives you time to find and build a suitable O/D tranny, and then your car will only be down a week or two, as you fit it into your chassis. And as to the engine, again you can spend an entire winter building your powerhouse the way you want it, and drop it in in the spring, over a long weekend.Eventually you might decide that the gears are just too low, and so you gather up the parts, and when it's ready, it rolls in in a matter of hours.
With the turbo combo, It is more or less an all-or-nothing deal. If you don't upgrade the tranny and rear at the same time, it just breaks. And then there you sit, all sad-faced knowing the clock is ticking.

And don't forget the suspension, steering and brakes. With added power, comes added speed requiring the chassis to keep up. Again, with the turbo, you can get into an awful lot of trouble relatively quickly. The V8 is a little more relaxed outta the gate, and doesn't usually wake up until a later on down the road.

Obviously only you can make the final decision, so all the best to you, and may all your schooling end in A-Plusses.

AJ/FormS said:

I can't argue with what's been said, but I'd like to throw in another option.

To travel 80 mph for hours atta time and realize good fuel economy, and hit 14's is not rocket science. But the roads to get both are a bit at odds withe eachother.
The tricks for the former are relatively simple; light weight, low rpm, and small engine.
The tricks for the latter are just as simple; a favorable power to weight ratio.
The turbo is a very effective tool to make both happen.
If your pockets are deep and you have lots of time, then the turbo route will certainly get you there.
But your goals do not necessarily REQUIRE a turbo slanty
But in NA (normally aspirated) mode 14s are easy with 275 hp, and certainly possible with a tad less. So that means almost any 360 will get you there, even a LowCompression 2bbl 360 has the potential. It however will need some help. And a 3 speed automatic is not gonna do it.
To cruise at 80, comfortably requires an rpm of under 3000. To get favorable fuel mileage, the Rs will need to get down to 2000 or thereabouts.
So here are the final drive ratios(FD) to hit all the bases NA.
Quarter mile; With a junkyard 360 hoping to hit 90 at mid 14s you are gonna need to trap optimally at something like 5200, so 4.56FD will do it. You will want at least 3 gears to get you there.
80 mph cruise; to hit 2000 will require a 1.92FD ratio.
There are no current appropriate 4-speed autos that can turn a 4.68 into a 1.92, as this requires a .42 o/d ratio.So a compromise will be required. A .69 is available.
So now we need to bias things a bit.
No 1, the junkyard LC360 is out. You are gonna need more power to pull a lower gear to 90 mph and you are gonna need more efficiency to up the mpgs at a higher cruise rpm.
So what kindof ratios might be more appropriate?
Well with a .69 o/d, lets bias for mpgs and choose 2200 for a cruise rpm, and 27 inch tall tires(255/60-15). This will be 3.23s. So then it remains to build enough power to hit 90 with 3.23s. With a 360 as a base this is pretty easy. You just need the usual mods such as headers, a 4bbl and reasonably high compression. The stock 360 cam will maybe get you there. A 220ish fast-rate is almost guaranteed to break 100mph, and I built one that hit 106 with 3.55s and a 4speed.That's a PW of 10.8, so at Dart weight of 3350 say(car and driver), that is 310hp.(Did I mention it was easy?). (106 is actually in the twelves)

So there is your NA recipe; small high efficiency engine(360) with an O/D auto and 3.23 gears, plus light weight(3350)

It should be said that mid-14s could just as easily be achieved with a teener. Hitting 14.5 requires a pw of just .060. At 3350 pounds, this is 200 hp. The teener however is gonna need optimum gearing. It's not gonna do it with 3.23s. So you will have to bias the teener for the ET, and then your 80 mph targets will be compromised. Well the teener could do it, with a stroker kit.

So now what remains is cost and uniqueness, and time.
As to cost;
So sure the turbo slant can do it without the O/D. But the stock 7.25 is not gonna last long putting up with all that torque. So the slanty needs a rebuild with a hi-flo head, plus a complete rear and beefed up tranny, plus the turbo kit.
The NA kit is a Hi-Compression unported 360, with an O/D auto and the stock 7.25 will last a long time with nothing more than a good-working SG.
As to uniqueness,
yes the turbo slanty fits the bill.
As to time
Since you will be doing all the engineering on the Turbo kit, Things take time. A lot of time. And one day the thought will enter your mind;"sheit if I would put a V-8 in this thing, I coulda been driving it 2 summers ago"

See the V8/904 route is quick and easy, and the combo can be fine-tuned as you go.Even with 2.76s out back, the V8 will motor along nicely doing a reasonable job in stock form.That gives you time to find and build a suitable O/D tranny, and then your car will only be down a week or two, as you fit it into your chassis. And as to the engine, again you can spend an entire winter building your powerhouse the way you want it, and drop it in in the spring, over a long weekend.Eventually you might decide that the gears are just too low, and so you gather up the parts, and when it's ready, it rolls in in a matter of hours.
With the turbo combo, It is more or less an all-or-nothing deal. If you don't upgrade the tranny and rear at the same time, it just breaks. And then there you sit, all sad-faced knowing the clock is ticking.

And don't forget the suspension, steering and brakes. With added power, comes added speed requiring the chassis to keep up. Again, with the turbo, you can get into an awful lot of trouble relatively quickly. The V8 is a little more relaxed outta the gate, and doesn't usually wake up until a later on down the road.

Obviously only you can make the final decision, so all the best to you, and may all your schooling end in A-Plusses.

Click to expand...

I half disagree. Any drivetrain mods you state would be required for either a 360 or a slant six. The drivetrain, doesn't know what engine is in frontof it, only the amount of torque applied. The amount of torque required for a particular result is the same, no matter what engine is used. Any inexpensive (relative) auto OD trand, will require floor and crossmember mods, in an "A" body. Actually the suspension, steering and brake uogrades required, would be greater for the 360, do to the increased weight, over the turbo slant. A 7 1/4 rear woiuld not hold up any better to a 360 then for a slant. (PS I ran a 7 1/4 SG behind a 3200 lb nitroused slant for many years, with out breaking it) My slant was making about 400 ft/lbs torque at 3,000rpm. Either way can work, and each has it's own challenges, and expenses, just different.

If you want a car that can do mid 14's and get 30 mpg on a budget, buy a used late model something.

I did a draw thru turbo 170 slant, back in 1979. Now you must keep in mind, back then there was not much turbo info available to hot rodders. No, "boost timing masters", no AFR gauges, etc. I did break parts learning how to tune it. 65 valiant street/strip car. About 2900 lbs with me. mid 13's at 100 mph, and about 18 mpg on the street. 7 1/4 rear 3.91 SG, 22 inch tall slick on the track and a 28 inch tall tire on the street, 904 auto, with a 9 inch converter. Turbo was a Rajay off a Corvair.

Well, I'm glad you only half disagree.
I have already built a 360 to go 106 in qtr and to get 32 mpgUS, and with just a 223 cam .
The turbo'd slanty will not be significantly lighter than the NA360.
And the turbo slanty can be set up to make a lot of torque a little off idle, perhaps more than the NA 360 with an 1800TC. So if it hits too hard and goes up in smoke, perhaps a lazier V8 might 60ft better on the street.
I too have put lots of torque through a 7.25. I choose the 8.75 cuz I can slam a different chunk into it in about 75 minutes or less, laying on my back in the hot sun.Everybody has had different experiences with 7.25s, mostly not so good.
I just wanted the OP to hear a bit about the NA side of things.I was purposely vague.
And I left the chassis paragraph until the end as a reminder that money has to be budgeted for these upgrades, regardless of which powerplant the OP chooses,cuz upside down and on fire is not an option, for anybody except maybe JohnForce .