5.0 vs 5.8

[kntr]

Does the 5.8efi have a lot more noticeable torque over the 5.0efi? Anyone swap out their 5.0 for the 5.8 and be disappointed? I cant decide if I want to throw a good set of heads on the 5.0 or swap out the 5.0 for the 5.8.

Thanks

 

[COBlu77]

I wasn't overwhelmed by the difference. It wasn't a WOW. There's more torque, but worse mileage. If you have a tired 5.0 or you get the right deal on a 5.8, it's a natural upgrade. It's a bigger pain to go EFI with the 5.8.

I just happened to run across a 5.8 that the guy was getting ready to put into a 65 Mustang, so it already had everything I needed. I just dropped it in and conneted the injectors and other sensors. I think if I get it dyno tuned and programmed, it could be better.

 

[bigmuddy]

kanter, I don't recall the numbers off hand but the 5.8 has more torque and less overall HP. Unless you find one real cheap, I would consider doing a head/cam swap and or stroke the 5.0 but thats just my opinion.

Ben

 

[kntr]

The 5.0 I have only has about 55k on it but its just..... well slow. I drive it on the street and I just want a little more out of it. I dont use it for offroad much and I want it to be reliable.

I run a built AOD, 4.56s, and 34" tires. I was just hoping for a little more.

 

[Slick]

:-[

that's kind of funny, it seems this topic comes up a few times a year and each time it seems there are diffrent opinions forming the majority...

My Hoop-dee is sport'n a 351... BUT it is pretty well built to the hilt (and came that way) and I've not driven an EB with a 302.

That said, I HAVE driven F150's with a 302 AND a nearly identical F150 with a 351. NOW, I am not able to site HP or torque specifications to you HOWEVER, my observation is that the 351 seems a better mate to truck type vehicles. There just seems to be more... "Ooomf" for the lack of a better term.

On the other side of that coin, I KNOW a 302 in a car like a mustang ends up be'n quicker than the 351's... in feel if nothing else. MY OBSERVATIONS are that the 302's get MOST their power at a bit higher rpm's BUT they also seem to get those R's faster... and the stroker 302/347's SEEM to perfom like a 2 stroke dirt bike, sort of like they have a power band... IE, once ya get the RPM's up and you keep them up you have MONSTER power, but if you feather the accelorator it drops off and sort of needs to spool back up...

so all that be'n said, it all depends on your drive'n needs/style, the tune of the specific engine etc etc. BUT in short it's my opinion that while there is not MUCH diffrence between a stock 302 or 351, the 351's GENERALLY are a bit better aplication for trucks & SUV's.

%) hope this actually help'd ya & you don't feel less smart after read'n this.

...I digress

 

[classic4x4s]

This is not exactly an equal comparison, but I have a '74 with a built 351efi and a '71 with a carb'd 302...the 351 is a lot more fun!

 

[Slick]

%)

LoL... check that out, ya basically said what took me 2 pages to say (or try'n to say) in 1 sentance!!!

hehe, if we got paid by the word my post is better... BUT I think the point get's to ya A-lot sooner how yer relay'n it! ;D

 

[kntr]

It would probably be a little cheaper to change cam and heads on the 5.0L though, correct?

 

[Slick]

...depends on what ya want to gain. they have the complete stroker KITS for the 302 w/all ya need in the same box. Or it's pretty cheap to find a good running 351 from a donor vehicle.

You'll see a sum-what noticable improvment with heads & cam, but if yer look'n for NOTICABLE power gain... you'll need a bit more... all depends on 2 things, #1-YOUR vision/goal & #2- amount of $$$ to spend.

 

[kntr]

Lets say around $1000

 

[Slick]

well, if what you have is basically in stock form you can find a decent 351 for about $500 and you'd have the other $500 spent by the time you drop it in.

And you'd have to check jegs & summit to see what you'd be spending on the parts to make yer 302 you have now nice and trick.

so... 6 in 1 & 1/2 doz in the other. I'd pick which sounds easiest to you, an engine swap OR tear'n into what you have and beef'n it up.

AS you know you can drop $10k on parts alone for a Focus motor if you want, ya just need to figure out what ya want to get in the end and decide what suits you best in-so-far-as achieve'n that.

LoL, I know I sound like a politican, but it's a personal kind of decision.

 

[kntr]

I called my Mustang guru budy. He said try a kit like this;
http://store.summitracing.com/partd...25232+400098+1011+4294857931+115&autoview=sku

But I dont know how that would work in a bronco every day driver and its $2k.

 

[Slick]

Try LKQ for the 351 swap. You can find a 351 out of OJ's white bronco all the way down to the CPU, EFI % roller cams for about $2k and that's basically a simple engine swap.

the only down side to the build up on a 302 is that it seems that in SUV's or trucks, if you let the RPM's drop the power dosen't come right back like a switch/instand.

The whoop ass neck break'n way to go seems to be the 351 stroked out to 408!!! I haven't herd too much bad about those aside from the kit cost and how often you are seen @ the gas pump.

 

[SaddleUp]

I paid $800 for my 5.8 and it was a very noticeable difference in power. Especially when pulling with it. Only a slight improvement in fuel economy though. (Gained about 1 MPG over the 5.0 it replaced although that one had gained a couple MPG over the 302 so the 5.8 ended up about 3 MPG better than the orginal carbed motor)

 

[BUCKETOBOLTS]

I've always been told "There's no replacement for displacement." I decided to build a 351W to replace my 30 year old 302. It wasn't any more expensive to buy a stroker crank than to have the stock one turned. So fo about the same money as a stock rebuild I have 393ci. And yes you can feel a difference! When you can bark 36's on dry pavement(not recomended with factory Trak Loc, ask me why) I'd say there is a considerable gain in torque.

 

[tabascom16]

In stock form you problaby won't see horrible noticeable difference (although I know someone with a fuel injected 351 from a Thunderbird and it has some good power.

If I just had a 302 to work with I would get an aftermarket intake, cam, and headers. That will really help the engine out. I wouldnt waste money putting aftermarket heads on an engine until you have at least those 3 things above. And if I would waste the money on all that I would definatley be putting it on a 351 and not a 302.

I went the 408 route with everything aftermarket so I can't tell you from personal experience but a few aftermarket parts can do you wonders even with stock heads. I get about 7-8mpg but even with 35inch tires my Bronco could give a new GT Mustang a good run for its money.

If you want fuel economy you cant have balls of fun with tons of power. It just depends what you really are looking for.

 

[kntr]

Ive decided on keeping the 5.0 and just leaving it stock for now. One day Ill do the 351stroker.

 

[tabascom16]

You will problaby get the urge to do the 351 stroker sooner than you think. Get the parts yourself though and have a machine shop put it together for you. It was way cheaper for me to go that route and I know I have all good quality parts in my engine. I'm a strong believer in crate engine manufacters cutting corners. I feel there is a reason they just get descriptive on some engine parts and not mention name brand stuff.

For about $5250-$5500 ($1300 of that was labor and balanceing from the best machine shop in the area) I have myself a pretty nice 408.

 

[rjlougee]

Having driven a 302, 5.0 and 5.8 in the same basic EB, I'd take the 5.8 over the other two and say it's WAY more fun, etc... If I had $1000 or so to spend, I'd try and get $600 or so for the 5.0 and sink that into the 5.8.

The later model 5.8s are roller cam equipped, and that makes them rev quicker like the 5.0s, a few more HP due to the lower frictional losses and there's not a lot of difference price-wise.

I can buy a '94-97 5.8 for $750 or so, add the Fox swap 'Stang pan for $150 and a low profile intake (to get it under the hood) $300-600 and you've got a lot more engine and it's going to make you smile!

Personally, I'd never stroke a 5.0 vs. swapping in a 5.8 UNLESS class rules required it. Bigger mains and bearings in the 5.8, etc... Then, when you're bored of it in a couple of years a $350 crank and you're at 396 CI. Same truck rods, no block clearancing, etc...

An AOD is like a C-6, a HP drain. The 5.8 won't care, the 5.0 feels it.
Joe

 

[kntr]

Im going to call the local junk yard and just see if they have a 94-97 5.8 and find out how much tomorrow. Im just curious now.

Will the stock 19lb injectors be enough? What all will I need out of the truck?