Question about performance options

Looking to get more out of my truck without making it hopeless in terms of economy. I've got the 5.7 hemi in an 05 with the 5 speed auto and 2wd.

I was wondering if it'd be worth it to convert to a manual when the tranny goes, or swap in an 8-speed and/or a bigger engine{when the engine goes}

I've also contemplated a 4wd/awd conversion for traction since trucks are so light in the rear, and any power adders would only worsen that {turbos and blowers are both quite heavy. And typically in the front}

Looking to retain 12mpg city and about 17-18 highway if possible with 400-600 wheel HP. I also want a true 6-speed or better transmission.

5 seems like the gears are too long to me{not to mention, it's slow to respond to stomping on it because it'll shift twice. In two slow stages. And it has poor response when I only wanna give it a half stomp, probably due to not having enough gears}, and I've read that the 6-speeds just have second gear split or something?? Either way, it sounds kinda bass ackwards to me.

I figured if I swapped the engine AND went with a manual tranny, there would be as few problems as possible. Either way, I just want to know and learn more before I even decide on what path I might take.

What engine are you thinking of swapping in? There are a few good options with keeping your own engine and building it. The hemi is a great place to start.
I'm not sure an 8 speed swap is doable. Heard people bring it up but I don't think it's happened yet. I could be wrong.
Are you just wanting to change transmissions for more gears or just more holding power? A 46rh trans swap is pretty popular with your truck, it handles way more power, but you still only have a 4 or 5 speed.

I was thinking of going with a bigger Hemi. I want a little more RPM and more base power to work off of. So either a 6.1 or a 6.4.

If I were to build my current one, I don't wanna stroke it too far because I still want it to be optimal for a potential FI setup in the future{heard that anything past a 3.8" stroke isn't good for FI. And I still want it to rev to 6.5k {though I don't anticipate going past a 7k redline in a street/daily driver, full usage truck}

IDK if or how much you can overbore a 5.7, but starting there would seem like a better first step than going to stroke it. I want 6L-7L of displacement in the end. Probably on the lower end of that, with mild H.C.I.E. mods and a small-medium twin scroll turbo bringing it up to the end game power levels I want while [hopefully] increasing or retaining efficiency at low engine speeds/cruising.

As for the transmission, in something this heavy, I need more gears. A 4 speed would not only be horribly long, or have less top end, but it would get worse economy. So I'd have to have a 6-8 speed transmission that can hold more power than stock.

For my minimum wage ass, I wouldn't anticipate anything past 700HP and TQ at the wheels dead reliable. It also has to be able to tow. I also want to convert to a 4wd/awd system with 3 locking diffs that act as limited slip when unlocked. I like the 3.92 gears, but might go with 4.11's. Depends on my final tire/wheel combo [among everything else] with the 1/3 to 2/4 drop I want to do.

{{All a pipe dream, I know, but...}} Can you think of anything that might fit such an application?

Not for cheap haha. For a full built engine/transmission turbo build you are gonna spend 10 grand+ in a scary fast way. You'll find out very quickly Mopar vehicles are more expensive for parts. You'll be fine with a stroker and boost. A 5.7 will reliably stroke up to 6.4 (this is what I'm doing right now), you can use a 6.1 hemi block and I think get it up to about 440 cc. The 5.7 doesn't have much room to overbore, maybe only .030 or .040 over. The 6.1 has a bigger bore stock, with the same stroke.
With the transmission the final overdrive ratio is what's going to determine your highway mileage. I'm pretty sure they are all close to the same on the last gear. The 545 final overdrive gear ratio is .67. You might only be using more gas around town with only 4 gears.

Been doing research on this just now. Problem with a 4 speed is that most of my driving is in the city.

Good news is that there's a tranny that'll work. The ZF-8HP90 can handle 664 lb-ft and should have a version that comes with integrated torsen AWD, as the article shows an 8HP55 with it on there.

Supposedly, the ZF-8HP70 goes for 4k retail, so worst case is that the 90 would go for 5k? IDK if that would be WITH the AWD setup, though, so hmmmm.

This is a tranny that will bolt up to a hemi? If you do a different transmission, you probably need a standalone transmission control module, and possibly your own pcm flashed or replaced to a manual pcm so it won't know the trans is different. Also if you want a performance truck, the 4wd is kinda looked down on, mostly just extra weight. The majority of the race trucks with gas motors only use 2wd. If traction becomes an issue, buy some slicks

It's a chrysler product. It's a variant of the 8-speed already in 4g rams. It should have a bellhousing that will work.

Also, 2wd is a nono for me in a powerful truck. Especially when adding more weight to the front {turbo system}. Slicks won't work on the street. Too small of a rim, too high sidewall, too small of an overall height. It'd look like sht to me. I couldn't roll with it.

Plus, again, due to weight bias, it'd be a deathtrap in the rain. It's already pretty bad.

So unless we can get/figure out a cost effective IRS system with a corvette style transaxle and a rear mount turbo setup that won't lag horribly due to having to charge a ****load of volume {and therefore have poor throttle response} then I'll end up HAVING to go with an AWD for overall traction.

Especially since I want to run a 305/50r20 or 305/45r22 street/sport tire instead of a drag slick/radial, already. I mean, if they made SHP or UP tires or drag radials in a 31-33" overall height, 12" width, and for a 19-22" rim, I'd be game AF and might run 2wd if it would grip. But in a truck, rear grip will always be an issue due to weight bias, which is due to how they're designed.

Besides. AWD DOMINATES no prep events, both street and strip. Just look at that Tesla guy destroying 1500HP+ cars on the street and on no prep in the 8th.

Either way, I'd pretty much have to go AWD for my safety, goals, and peace of mind. But it would be a hell of a ride, either way. Plus, If I ever wanted to go Ram Runner style.... Well, the AWD would already be in place. ;D

Gonna get into gears sometime in the next few months. Going 4.56's. Truck currently has an LSD and 3.92's as far as the tech told my dad when it was worked on last year on a recall.

After that, or perhaps before, I think I'm gonna do a full intake kit, as I'm starting to think that my K&N drop in is poorly affecting my fuel economy.

Is it? Should I try to return it and go with a stock paper filter? Or would a full intake kit do me better on both the economy problem and performance front?

I’m running an S&B intake on my 03. Honestly, by itself I couldn’t tell a difference. The only reason I did it was to complete an entire engine build with a full exhaust, headers, tune and eventually a cam and stroker. By the time it’s all finished I’m sure the stock air box wouldn’t be up to the task. But I watched my mpgs carefully before and after the intake, literally no change better or worse. Some other people may have had better results. I would only upgrade it if there are major plans down the road

My buddy had a 04 quad cab 1500 he had done over to make it a 6.1. Not sure if he had it bored over or what, I remember he had the 6.1 cam and whatever else put in, plus he had 4.56 gears swapped in. With a lil weight in the bed and a 1st gear launch that didn’t loose traction you could see daylight under the front tires, no lie. That thing ran good.

Well, you know me. Indeed there are. I'm just wondering what's making my mileage suck so bad. I'm getting an indicated 10-11 all city, and I know the display is consistently 1mpg off, so that's 9-10 all city, actual.

Before my dad passed, when he was driving it, it usually indicated in the 11.5-12.5 range.... And I've heard people say the K&N drop in was a potential culprite, getting claims of a dude getting 14 going down to 9, and then getting 14 again with the paper filter.

Of course, I'm stubborn and want the reusable thingy, but not if it's going to cost me in gas. Of course, with more mods planned, I'll need a full intake as is, but would going to a full intake kit be any different than the drop in, if, indeed, it IS the drop in causing this fuel economy issue?

Could it be the throttle body, plugs, or wires? Should I attempt changing the latter two, and cleaning the former?

EDIT:: BlackBeautyHemi; What size tires did he run? I'm not anticipating going to car tires, or anything shorter than a 32" overall height....

If it makes you feel better, I only average 10 mpg right now. Before the cam it was only 11.8.

Pipe dreams

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600hp turbo'd 3rd gen AWD possibly manual trans so much power it wont even be safe in RWD and errrrrrr minimum wage and is worried about MPG! [emoji23] o man pass that **** my way brotha lol

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Build a prius [emoji41]

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ramportin1 said:

600hp turbo'd 3rd gen AWD possibly manual trans so much power it wont even be safe in RWD and errrrrrr minimum wage and is worried about MPG! [emoji23] o man pass that **** my way brotha lol

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That’s a good summary haha. Hey I’m all for going for a dream build. But you also better understand all that is gonna cost you about 20 grand easily. At minimum. That’s doing it yourself, and you would have to be a very good mechanic to begin with. I don’t think the manual conversion awd thing is gonna work. There is soooooooo much stuff that goes into converting a transmission. Let alone turning a 2wd into a 4wd.

A turbo increases fuel efficiency power for power, displacement for displacement. If it's not driven like a *******, it should do okay.

I'm not building Leroy the savage of trucks, here. Just something that can get out of it's own way. The only reason it'll have such power in the first place is due to the large displacement being combined with the fact that it'll be turbo'd.

I mean, a 6.1 with a 'factory' sized turbo {sub 55mm} at 'factory' boost {sub 15 lbs} IS going to make power. Not 1000+ HP, but with a mild setup otherwise {cam, heads, intake, headers, etc} 600 or 700 isn't unreasonable, right? Cars from the factory get 300 out of a 2L and over 30MPG.

Is it not reasonable to believe that I can at least retain my current mileage by building the engine as if it were a factory turbo'd vehicle? Especially with an 8-speed trans and being slightly lowered with a few aero improvements?

chrisp2493 said:

That’s a good summary haha. Hey I’m all for going for a dream build. But you also better understand all that is gonna cost you about 20 grand easily. At minimum. That’s doing it yourself, and you would have to be a very good mechanic to begin with. I don’t think the manual conversion awd thing is gonna work. There is soooooooo much stuff that goes into converting a transmission. Let alone turning a 2wd into a 4wd.

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Lol yeah for sure man. You were being a good sport! Now time to get back to your frankenhemi [emoji41]

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ramportin1 said:

Lol yeah for sure man. You were being a good sport! Now time to get back to your frankenhemi [emoji41]

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Bro I’m trying, still waiting on my block to get back from the machine shop. Hopefully it will be back next week and I can get the kit ordered right after. Still about a month out

There’s no doubt you can get the power out of your hemi, that’s been done on ALOT of trucks and cars. That’s the “easy” part of all that. You might still keep a decent mpg. But as far as I’m aware nobody yet has successfully gotten an 8 speed converted over, I think I saw some people flat out say it won’t work for a bunch of reasons. If it was possible and practical, someone would have definitely have had it done by now. And if not, and you wanna be the first one, I’ll say it again “EXPENSIVE” haha.
Most of your plan is doable, I would say the full time awd is the only thing that’s alittle far fetched. Hang around some Performance truck forums for awhile. There’s a lot of knowledgeable guys who have already wasted a lot of money on different things, it’s good learning from that first. Good luck!

@op, if you want to achieve all that minus the awd theory, then go get yourself a bank loan for 25k$, if your credit is shot then pm me I know a guy. Lol