Hi everyone,
I have a 89 5.0 out of a truck that I am planning on building and putting it in my jeep. It will be going into a c-6 trans that has a shift kit installed in it. I have been looking around for the best way to build this motor. I want to make some serious power. I am open to doing about anything to this motor, Stroker, heads, cam, intake, or whatever else, Now it seems like there is alot of parts for the mass airflow style 5.0's but not the one i have with like the twin throttle body setup, should i switch to the mass airflow? will that get me some more buildable parts, If i do that will i need to get the whole harness and computer and stuff or what? I dont care about gas millage or anything I want something that will just make that thing go like no other. The only thing i dont want to get into is a new computer system, but i know if i do alot of mods to it i will need to get bigger injectors and stuff but what would be the best combination to go with, and still use the stock computer. Is there anyone that can give some input that has maybe done this with a truck block and had really good results. All info appreciated, Thanks Steve

 

The 302 is notorious for not having enough low end torque. For your application that is pretty much what you need. You cold stroke to 347 and get the torque, but that would cost more than just going to 351 W.

 

First off Steve, let me say welcome aboard!

Secondly, on top of the info from GA302, you will also need to consider what trans you are using. Not too many C6's came behind the small block, unless they are intending to hammer the heck out of it. The C6 will also suck down about 30% of your power. What are your intentions with the recipient vehicle? If you just want to go fast, get something different to do it in. Considering you are talking FI and such, you will need the wire harness from the donor to go with the motor. There is going to be a lot to get this together, hopefully time and money are not a factor for you...

--Mike

 

the c6 is a great tranny, one of fords best IMO. it does use about 40-60 hp to run though, but if you are just mudding and such then it is perfect for you.

 

Stroke it to a 331, and put a blower on it, lot's of boost and it will fly.

 

Well I intend on using this for mostly offroading, but it will also have its fare share of time on road also. The motor i had in there befour was pretty doggy and didnt really spin over the tires too well, I got a good deal on this truck here that has the 5.0 in it so i got that since the 5.0 is a pretty standard swap into most jeeps. I like the fuel injection because ive had too much proublems with the carbs getting on hills or on rough terrain. I really had no idea that the c6 took that much power to run, but i would like to keep it since it is pretty bullet proof. And i would also like to keep the 5.0 rather than looking for a 351 because i already have this motor. Now if I were to stroke this motor to a 347 would it have comperable power to a 351? Would i also neew to get oversized injectors to get more fuel in there, or will the 347 work well with the stock components. I was thinking about getting a cam and maybe some heads also, but im not sure if that would be a waste of money and would not add much more power. Thankyou for the help I am pretty excited to rebuild this motor, I have all winter to work on this to get it readdy for spring but if i want to do a good job I need to start this soon. Thankyou very much, Steve

 

A 331, or 347 will make a butt load of power, and although we may get at high RPM arguments, gears will always put you in your power band.

 

they make holley carbs with spring loaded jets for offroading.

 

I agree, but it would be cheaper to buy and build 351 than stroke 302. No fuel system problems either.

 

I am doing a 5.0 swap in a jeep as well. It's an 89 wrangler.

I would not recommend the 351 in a jeep....the weight is a big factor as well as clearance. The 351 is wider and taller...as well as over 100lbs heavier when assembled. The 351 would fit but...be a lot tighter. It's not necessarily cheaper to build a 351 over a stroked 302. Maybe the shortblock is more expensive, but in this guys situation he'd have to buy a block (351s arn't as pleantiful), and change over all the parts that don't interchange (like the distributor, balancer, flywheel, exhaust y-pipe...etc etc). In the end a 351 build is going to be way more.

Don't go 347 as it's longevity is short, either do a 302 or 331. The 347 is not a bad motor, but better left to drag racers. About the 302/331, building the top of the engine is the same on either version, the only differences in the bottom are cost (assembly is only a little different), and probably 30ish ft-lbs of torque more. The jeep is pretty light so either one would work great, the torque is not a massive consideration with the light jeep. We're probably going to do a 331 in the jeep wranger I'm working on. My truck weighs close to 6000lbs so the 393 was needed for torque.

The C6 is not the only tranny that takes power to run it, all auto trannies are like that (did I mention I hate auto trannies...)....but the c6 is a perfectly fine transmission to use so go for it. My dad had one in his F-250 and I was very happy with that transmission, 140k error free miles (probably maintance free as well, dad is not good about that stuff).

The EFI will be easy to run, the fuel system will have to be modified, but do-able. I havn't started this swap in the jeep yet, it's in the planning stage. You could use the wiring harness of the motor you have, I'd look over it for bad connections and re-work it. Ford built these wiring harnesses very well, so don't hesitate to re-use one if it's in good shape.

I say get a 331 with some GT-40Y heads from diversified products, $700 for a take off head. It's a brand new GT-40Y head that was bolted on a crate motor, never fired, but removed so they could put a different head (the Z head) on the crate motor. I just bought some and they came the other day. With a mild cam and 1.7 rockers, that motor would push out about 360-370 hp. Nothing serious needs to be done on the bottom end (don't need forged pistons or H-beam rods), be about a 5800-6k rpm redline as well. Check out coasthigh.com for some prices on 331 kits, they're tech is very helpful (I've talked to Mike like 10 times about my 393, great guy). You can buy their shortblocks or since you already have a block, buy their kit and install it. They've got some good stuff, I bought my 393 from them and it should be here in a week or two. Whatever you do about the heads...don't have to get the GT-40Y's....get aluminum heads. It will take another 50lbs off that front end. It's important to keep that front end weight as low as possible (I recommend even putting the battery in the back). With that much power you need that rear end planted well and have as close to 50/50 weight distribution as possible for optimum performance.

Definitely switch to MAF...you might want to hit up a mustang GT in the junkyard. ****** it's wiring harness, computer, upper/lower intake, etc etc..anything. The mustang and the F-150 use the EEC-IV EFI...but the mustang's has MAF and the stock computer will run that engine fine. You may want to get a custom computer chip for it to tune it for better power though. I think the truck intake will be too tall for the jeep hood (not sure about fitments yet as I havn't actually done it) but it is also an intake made for low end torque. The mustang intake would be better, look better, and the aftermarket throttle bodies/air intakes are cheap/good.

 

well i think im going to go with the 331 since it seems like the power bands are mostly the same? right? Now if i go to mass air flow, is this really any better? what is the difference? can you tune in thefuel more then the truck style? Will the 331 or 347 run well good with just the stock injectors and stuff or is it going to need an adjustible mapp sensor? Thankyou for all the information, i still have some more questions but this is all i can really think of right now, sorry it takes me so long to respond but i have been super busy these last few days. Steve

 

make sure you get the efi stuff off of a 89-93 5.0 get or lx mustang.

 

331 would be a great choice, I think that is what we'll end up doing in our jeep. The MAF is definitely better, it's what will allow you to run that motor w/ the stock computer. The MAF can adapt to flow changes (more horsepower) so there is little tuning to be done on your own. It will probably need 24# injectors or higher, but it depends on what kind of power you plan on making. It's best to leave a little comfort room w/ injectors and not have them at max capacity. I believe you meant to say adjustable fuel pressure regulator. That is not necessary with the correct injectors. Sometimes people will use an adjustable FPR to compensate for injectors on a speed density system (not MAF), but mainly the adjustable regulator is for racers who need to fine tune.