Heads and cam swap

[93ragtop]

Currently, I am working on plans to get a 5.9 magnum in a 87 4wd, 5speed 3.54 geared dakota.
I already have converted the trans to the nv3500 , and have installed an electric fuel pump.
My next step is to find a 5.9 magnum, convert to a carb setup, (already have a holley 670 carb) and use a hei ignition.
Plan to disassemble the motor and hopefully only have to freshen up with bearings, rings, and gaskets.
In time, I would like to upgrade the cam and heads.
Now, to my question,
I wanted opinions on the following parts, and what kind of power you think it may make. Please keep in mind, I will have to use stock manifolds or no more then shorty headers. Love to have long tubes, but no way to fit on this truck.
This is the heads I was looking at. EQ Cylinder Heads for 5.2L/5.9L Magnum V8 - STAGE 1
And this is the cam. Camshaft - Stage 2 Regrind

I know this is an a body forum, but it seems that there are some of the most knowledgeable magnum engine people on here to ask.
Thanks for your help and opinions.

 

[rumblefish360]

[email protected]/.520 lift will show a nice gain. I can't guarantee it'll make 360 hp, but it should be quite a powerful total street engine.

Your head selection will unleash the power potential very well with that cam.

A shame you can't squeeze headers in there. So to thtat end, make note of the exhaust manifolds casting numbers and check against the best one available. There outlet is IIRC, 2-1/4 inch. IMO, getting a dual 2-1/2 exhaust pipe exhaust bolted up to those manifolds would be very good for power output.

 

[dano]

Trucks need torque, 4x4's have lots of running gear loss. What tire size are you going to run? Estimated Weight? Pictures? I always like the pre-"goldfish" Dakotas.

 

[93ragtop]

[email protected]/.520 lift will show a nice gain. I can't guarantee it'll make 360 hp, but it should be quite a powerful total street engine.

Your head selection will unleash the power potential very well with that cam.

A shame you can't squeeze headers in there. So to thtat end, make note of the exhaust manifolds casting numbers and check against the best one available. There outlet is IIRC, 2-1/4 inch. IMO, getting a dual 2-1/2 exhaust pipe exhaust bolted up to those manifolds would be very good for power output.

Rumblefish, thank you for replying. You are one of the ones I hoped would answer.
Its my understanding that the 92-93 have the bigger manifolds. Funny thing cant find those new anywhere, but the smaller ones, everybody has. So I do need to be looking used for a decent set.
Another option that I considered was a set of stainless shorty headers, cut the flange off, and then use a band clamp to connect exhaust. The two questions would be, 1. is the collector at least 2.5 in.? and would there be room to make the down pipe fit.?
The exhaust basically has to cross over to the pass. side to go out....
Between the starter, torsion bar, front driveshaft, and transfer case, not much space left on the drivers side.
But again, thank you for your opinion!!

 

[318willrun]

If you get a good running 360 mag with under a 150k for miles, I wouldn't even do bearings/rings. These will push 300,000 miles without batting an eye.
They have around 245 hp (NET) hp from the factory, which would be about 300 gross. You'd get this with just a 4bbl.

• Heads are a nice upgrade
• Your 4bbl will add some top end power, as the keg intakes choke out the rpm's
• In a 4wd, you may only want to upgrade the heads. You may like the cam as it has good low end torque.
• You are correct with the manifolds, some have bigger outlets. A good dual exhaust ran off of those will aid in power too.
• Good Luck

 

[93ragtop]

Trucks need torque, 4x4's have lots of running gear loss. What tire size are you going to run? Estimated Weight? Pictures? I always like the pre-"goldfish" Dakotas.[/QUOTE

With me in it, weight across scales is about 4160 (im 190) with a full tank of gas. Tires are 255/70/15
The cam seems small, but I want idle close to stock.... But coming from the mighty 125hp, 195 tq. 3.9 motor, I feel sure anything is going to feel like a rocket compared to that!!

 

[93ragtop]

If you get a good running 360 mag with under a 150k for miles, I wouldn't even do bearings/rings. These will push 300,000 miles without batting an eye.
They have around 245 hp (NET) hp from the factory, which would be about 300 gross. You'd get this with just a 4bbl.

• Heads are a nice upgrade
• Your 4bbl will add some top end power, as the keg intakes choke out the rpm's
• In a 4wd, you may only want to upgrade the heads. You may like the cam as it has good low end torque.
• You are correct with the manifolds, some have bigger outlets. A good dual exhaust ran off of those will aid in power too.
• Good Luck

I will need to change the oil pan, so I could at least pull a few bearing caps and look..... Also, I assume a new timing chain, should be installed...... And would at least like to replace seals and gaskets before putting it in the truck. My plans are, if possible, keep it stock for now, and latter do the heads cam upgrade.
And thanks for your help!!

 

[rumblefish360]

Rumblefish, thank you for replying.
1. is the collector at least 2.5 in.? and would there be room to make the down pipe fit.?
The exhaust basically has to cross over to the pass. side to go out....
Between the starter, torsion bar, front driveshaft, and transfer case, not much space left on the drivers side.
But again, thank you for your opinion!!

No problem. This issue is solved by true "Hot Rodding" techniques! Use your head and follow along below with some imagination. The problem being no Dakota is listed at Summit as having a V8 until '93.

The collector size should be listed by the maker (and/or seller) of the header.
Look here at Summit. As said. Earliest year for a V8 would be '93. If there are changes, I am unaware. But it may, repeat, MAY WORK.

https://www.summitracing.com/search/part-type/headers/header-style/shorty/drivetrain/4wd/year/1992/make/dodge/model/dakota?N=4294924068+4294924002+4294948686
I don't know how much room is available. I have not been down this road.

These shorty headers often exit somewhere in the same - ish area that exhaust manifolds do. I don't think they will bolt up to the OE exhaust or exact location. BUT it could be done IF the header fits in with reasonable clearance. You would have to fab up your own. DONT be afraid of such things. I had a similar issue with a Jeep Cheif Wagoneer, 360, 4X4, auto. Installed headers, used the OE pipes cut up with auto parts store exhaust pipe connectors.

Both sides of the exhaust off the header connected together and into the stock exhaust there on back. Drivers side took a J bend off the connector and then another J bend to run it parrael with the passenger side exhaust pipe off the header. A 2 into 1 merged connector joined them into the exhaust pipe.

The same could be done for you or use some generic pre bent pipes. You'll need at least 2 maybe 3 J bends at the exhaust size you want and 3 exhaust pipe connectors. Cut to fit down, below, around the oil pan and then into merge with the other passebger side pipes.

https://www.summitracing.com/search/outside-diameter-in/2-250-in?N=4294895313&SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=individual exhaust pipes

Summit also sells "Y" adapters to connect the two sides. Or dual pipes into a single cat and/or just a muffler.

https://www.summitracing.com/search?SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=2 into 1 exhaust pipes

2 in, 2 out muffler thought;
1-1/4
https://www.summitracing.com/parts/wlk-17552/overview/
or 2-1/2
https://www.summitracing.com/parts/wlk-17553/overview/

An "X" pipe instead of a muffler is a fine idea as well. That leaves you with muffler choice where you want to put it. (Or them, as in a pair of mufflers.)

Do a search at Summit for Dakota exhaust kits.

 

[mderoy340]

You may want to call Magnum Mopar (Evan) and ask about a different regrind. That Stage 1 and 2 grind is on a wide LSA to work with the FI computer. With a carb and 3.55 gear I would go with a narrower LSA.

 

[318willrun]

No problem. This issue is solved by true "Hot Rodding" techniques! Use your head and follow along below with some imagination. The problem being no Dakota is listed at Summit as having a V8 until '93.

The collector size should be listed by the maker (and/or seller) of the header.
Look here at Summit. As said. Earliest year for a V8 would be '93. If there are changes, I am unaware. But it may, repeat, MAY WORK.

https://www.summitracing.com/search/part-type/headers/header-style/shorty/drivetrain/4wd/year/1992/make/dodge/model/dakota?N=4294924068+4294924002+4294948686

V8 (318) was offerered before '93. '92 had 318 mag, and 1991 had LA 318 TBI, and I think as far back as '89 shelby's had 318's. Not alot of difference in bodies, so I amd with you and would take a chance on the headers fitting.

 

[rumblefish360]

V8 (318) was offerered before '93. '92 had 318 mag, and 1991 had LA 318 TBI, and I think as far back as '89 shelby's had 318's. Not alot of difference in bodies, so I amd with you and would take a chance on the headers fitting.

Oh thanks! I thought they did BUT it wasn't listed at summit so I errored on the side of caution.

I also would give it a go.
Just remember once you try to install those headers and put a scratch in it or a bolt on it they're yours, nonreturnable.

 

[93ragtop]

That is my understanding as well.
The 87-90 are the flat nose trucks. All were 4cyl and V6. Except the 89 shelby 5.2L package. It is my understanding they used a different engine cradle, moving the engine slightly backwards so the pulleys would just clear the radiator. (still used V-belts) Then they sandwiched 2 electric fans between the radiator and condenser. The shelby was only available in automatic and 2wd.
91 was a 5.2L (LA) motor, but I think it had a serpentine belt system with a clutch fan. But the nose of the truck was redesigned, allowing 3-4 in more clearance. That along with the serpentine system gave enough clearance....
92-96 had the magnum series engines.

I think I could use any of the shorty headers made for the 5.2 magnum. The problem is the flange is going to be made to bolt to the small headpipe.
There may be room to cut that flange off, go with the slip connector on a 2.5 in collector, and make the exhaust......

The only long tube headers I have found for a 1st gen dakota (87-96) are the hookers. https://www.summitracing.com/parts/...year/1989/make/dodge/model/dakota?prefilter=1

Thanks to everyone for their input!!