Hey guys I just wanted some advice currently I have a 300 i6 in my 85 150 but I would like to put a v8 in it and completly rebuild it. I am not sure which sort of engine i should go with. I have done some research and the transmission I have will bolt directly on with a 302 or a 351 windsor. I am leaning towards the 351 what do you all think? i have full access to a garage and all of the tools I would need as my friend drag races, but he is a dodge man and he does not know much about these engines. I am planning to start this build whenever i can get my hands on an engine for a relatively good price and build it through the winter I plan on re building it pretty much from the ground up new cams and pistons etc. any ideas?

thanks very much for your input, JWGCROWLEY

 

The 351W.
There's no substitute for cubic inches.
Before making any recommendations on engine builds - need to know what you plan to use the truck for (street cruiser, towing, off-road, etc.). Is gas mileage more important than TQ/HP?

 

You will need to start with a engine from one of these trucks, or any engine will do but you will need to get a oil pan, oil pump extension, and dipstick setup from one of these trucks and swap it on to your new engine.

 

This truck is going to be my toy I want to be able to go for a drive on a nice day and not cost me an arm and a leg. But at the same time I want to be able to use it like a truck and be able to take it to me camp. I would love to get optimal power out of it. I do not plan on getting a lift kit or big mud tires trying to make it more of a muscle car would be the only way I could explain what I want.

 

Also how much would it roughly cost for a 351w are they hard to come buy? And I'm in New Brunswick Canada othe than junk yards do you have any suggestions?

 

You could by a crate engine from some place like Summit FORD Engine Assemblies - Long block Engine Assembly Style - SummitRacing.com You can expect to spend around $3,500 to $4,000 USD for a ready to run performance engine. It always cost more to build these engine piece-by-piece (but that's what I enjoy most about this hobby).

If you can find a truck in your local junk yard and get the complete engine, mounts, wiring, brakets, accessories, etc., that would make your swap easier - but I don't know if you'll save much money when you factor in the machine shop work and buying all the parts individually (I'm talking about performace parts (pistons, cam, lifters, heads, carb, distrubutor, etc. - assuming that's the route your going).

 

That is the route I plan on going with it as I do not have a bunch of money banked and I kind of wanted to put my own work it to and know really how it tics I usually have an extra 200$ a week to work with but I am definately open to any suggest you have to offer

 

Yes, the 351W is the way to go. Put a mild cam in it, like a Comp Cams 252H and you will have a lot of low end torque. Add an Edelbrock intake, preferably the Performer and not the Performer RPM, and an E'brock 1406 carb and it will wind nicely.

As for cost, the machine work will cost a minimum of $1k US. That's the figure my friend gave me for all the parts (pistons, rings, gaskets, and valves) as well as the machine work. I'm confident you won't find anyone that will beat that price, and probably won't be able to match it. Add the cost of the block, crank, heads, rods, pan, and valve covers to that, but the best way to get them is by buying a used engine - making sure like Dave said to get one for a truck. I've seen them go for ~$200 on Craigslist. Then there's the intake and carb, and CL is the place to find those as well, with the intake going for ~$100+ and the carb for ~$100. In other words, you are looking at $1500 US minimum to start from scratch, and probably more like $2000.

But, you could spend more on the heads and get quite a bit more power. These trucks came with smog heads that are awful on the exhaust side. Check out Thumper's Heads for some that flow really well without going to aftermarket aluminum heads. They'll make quite a difference but mainly as the RPM goes up, not at lower R's. Anyway, watch CL for heads as well, but do some research as you do NOT want large valve/passage heads as they will kill low RPM power.

Considering MPG, you didn't say what transmission you are running nor what axle ratio you have. But, the C6 auto and 3.50 gears are pretty common in these trucks, and assuming that is what you have and you build the engine conservatively I'll guess you'll see 13 - 14 MPG on the highway running a steady 60 - 62 MPH. I say that because that's what I got with that tranny and gears and running an engine like described. Go to a manual tranny and expect another 1 MPG. Go to an overdrive tranny and you'll see another 1 - 2 MPG. But, better heads won't help you on MPG unless you raise the compression ratio with them, and that will help.

Good luck and let us know what your plans are and how it goes.

 

I have a 4 speed manual

 

That's good as you will see better mileage.

And, by the way, my prices were for pretty standard parts, not speed or performance parts. If you want forged pistons, which aren't needed, it'll cost more. If you want hypereutectic pistons, they'll cost a little bit more but less than forged. The $1000 included a no-name cam, but to go with a good one like Comp's then add $150. However, the pricing did include Fel-Pro gaskets, a name brand timing set, a new oil pump, name brand bearings, etc. You'll have a new engine with those prices, and it'll have spunk due to the cam and intake/carb. But, it won't be a serious high performance engine. And, you have to do all the assembly.

 

The assembly is not a problem there my friend has been doing this for 20+ years he just doesn't know anything other than mopar when looking for a used engine what should I make sure of? I'm probably going to call around in a couple weeks

 

As Dave said, you need to find an engine out of one of these trucks to get the right oil pan, pump extension, and dip stick. As CB said, it is best to get the whole truck as you need the mounts and perches, the things the mounts bolt to and which are riveted and bolted to the frame as they aren't the same for the 6. And, you also want the wiring harness from the V8 as it is slightly different than that of the 6, but only if you run a factory tach.

As for the engine itself, one that hasn't been rebuilt is preferable since there is a maximum things can be bored/turned. But, if the engine has been rebuilt make sure it hasn't been bored past .020" over as you can go to either .030 or .040 then to clean up the bores.

 

Perfect and my trick did not come with a tach but I am planning on putting a sunpro super tach 2 on it

 

I've been scoping out engine for a little bit and I have not had any luck at all finding a 351 but there are many 302's that I can get with the truck would I be able to crank a good amount of power out of the 5.0

 

Not nearly torque at low RPM unless you spend lots of money.