Hello,

I recently purchased a 99 Dakota r/t. Looking to turn it into a bit of a wild animal but I'm hoping to have some specific traits and I need some advice.

My overall power goals for the truck are still up in the air but considering everybody and their dog seems to be making a 1000hp plus with turbos these days I'd like to keep my options open. If I could turn the boost down for normal driving but have big power on tap when needed I'd be very happy, possibly with a bit of water/meth? This build will have a healthy budget, but I don't want to purchase anything twice, do it once and do it right is the general theme.

First of all, I love the low end grunt that the r/t has but the top end is a little flat. Would there be any advantage to upgrading the cam if I still want that off idle power, Or can I just rely on a turbo to take over the top end?

Also I see a lot of people seem to go with an S475. Is that best for driveability or drag racing where you can spool up first. The truck might see a variety of situations, drag, drift, road course or general bastard driving so I want very readily available power. Maybe twins is better for me? If so which turbo's are ideal? I just put compound turbos on my 12 valve so I have one HX35 leftover.

I guess the biggest question of all is should I build a 5.9 magnum or just start drinking the LS Kool-aid? I like that it is already in the truck with cruise control and A/C and I'm fine with doing heads, intake and forged internals heck maybe even a block if need be. But does it make any sense?

Thanks

 

How much power are you looking to make? If your looking to make 4 digit hp the LS is the way to go. The 5.9 isn’t gonna cut it there. The LS is just more cost effective.

 

Ya like I said total hp goal is still up in the air, just curious what's possible in case I go off the deep end. The reality is this thing with 500 to the wheels would be plenty of fun

 

Unless you love the Magnum, or really hate money there's really no reason to keep it if your goal is more than say 5-600 rwhp. The Ls is a much better platform with transmissions to match. That said, it's all what you like, just be aware that you'll spend more for much less. I'd personally go 5.7 Hemi if you're set on Mopar power.

 

I just don't get why there are guys making well over 1500hp on 4 and 6 cylinder engines but this isn't feasible on a 5.9 magnum

 

Ya it's not a mopar thing, I just don't get it. If it all comes down to money then fair enough.

 

Head flow, engine architecture, and rpm. A stout bottom end, ample head sealing, and 4 valve cyl heads.

 

Many of those 4-6 cyl's are not cheap builds either.

 

Ok cool, that makes sense. Thanks for the info

 

It's a money thing with the Ls. There are plenty of parts out there to build a stout La if you want to.

 

Here's the thing, last year about this time I bought an old 12 valve dually and once I started buying parts, my god things got out of hand quickly. I really don't need that kind of power yet but once you start it's hard to pull the pin and go in another direction. I have a rock crawler project in the works as well so this 5.9 with only 90,000 miles on it would be a great power plant for it.

 

I'm currently installing a rear mount turbo on my 51 with a 5.9 magnum. Its completely stock at the moment, I plan on adding a new intake manifold to it as the stocker totally sucks for performance use, also at some point will add after market efi and ditch the stock injection setup. I also have plans to change the cam and heads down the road because they are also poor for performance, the bottom end i hear is good for up to 600hp but thats just what i've been told and have no real world experience with that. I plan on starting out with 6psi and work up to no more than 12 psi max, which should put me right around the 500-550 hp mark i believe.

 

The magnums also tend to have a problem with heads cracking too. So you’d have to add heads cam intake to be on even ground but the bottom end strength is questionable at less than your power goal.The LS is hard to beat since they are strong straight out the factory. The newer hemi is pretty strong too.

 

Ya good info guys thanks. The more I think about it the more I realize I should just keep this one a bit more reasonable. 500 at the tires is almost triple the stock 180 or so rwhp. If serious drag racing becomes more of a priority I'll look at putting an LS in something a little lighter and more aerodynamic. I just don't see the point in pulling a motor that has this few miles.

 

Need to change the thread title now. lol

 

Ya good point how about "Daily driver Turbo Dakota R/T (REALITY CHECK)"

Who knows, I might push the envelope a bit...

 

I'll say this, until you've driven a true 500rwhp street car, don't go thinking you need more than that. That truck is probably around 4,000lb. 500 wheel in that would be very fun and borderline unsafe unless you've done suspension work and have sticky tires.

 

Ya man I appreciate the thought. My diesel should be well above those numbers but it weighs 6500-7000lbs. I've spent a lot of time on dirt bikes so more power than traction is definitely a familiar feeling.

 

Like some have stated above. 450 wheel on turbo would be a good goal for a stockish block/setup. If you went with a built and/or stroker block you could do like 650ish. Luckily nowadays the dakota's are easily tune-able. If it was me building a stout street truck: use stock block and find another to build(forged) in the mean time, new cam, new engine quest heads with 3 angle valve job, hughes intake/throttlebody and turbo setup (reversed shorties with t70 ish size turbo. Dont forget transmissions and torque converter $$. Probably run high 11's with the ability to run 10's once the suspension is tuned and the boost goes up.

or slap in a 904 trans, strip the truck,, and run a blow thru e85 carb.

 

How important is it to deck the block and surface and perhaps o-ring the head for these type of boost numbers? When I put compounds on my 12 Valve it blew a brand new head gasket with ARP headstuds within 2 days. Machine shop guy said I probably could have just surfaced and o-ringed the head but I decided to pull the engine, deck the block and rebuild it anyways because it had some blow by. A lot of work but glad it's done considering the high boost levels in a diesel.

What sort of boost numbers would I be looking at with this build, 14 or so tops? Initially this truck was gonna be a stripped down multipurpose bastard truck but the interior in it is like brand new so it is definitely gonna stay. Bringing it in tomorrow for the out of province vehicle inspection as I bought it out of Alberta. Wish me luck.

Here she is