So i've been searching both this board and mustangforums.com for a verdict on whether it's better to go with a stroker kit or a supercharger. The field seems to be passionately divided. Here's what i have, what i do, and what i want.

I have a 1966 coupe with a mostly stock 1987 5.0L EFI there are a set of custom headers to fit the 66 coupe body. They sound gnarly. I've got upgraded suspension with new sway bars, a T-5 transmission, and an recently rebuilt 8.8 rear end.

I live in Seattle and this is a weekend car durring the 3 months out of the year we're not getting pissed on.

I want some more hp but just for street fun. I have no intentions on taking it to the track or anything like that.

Being that i'm not planning on reving it up to 5000rpms and going 125 on the highway. So i've ruled out a turbo because everything i've read says you get the power at the high rpms instead of a more even power that spans the entire rpm range.

I hear two very split opinions.

opinion #1 - "Just slap a supercharger on it!" There is a crowd that pushes the fact that these 5.0 engines can easily handle 6-9psi of supercharger without stressing the engine. I'm not sure i want that high pitch whine to drone out the low rumble of the pipes but that's small potatoes.

opinion #2 - Stroker kit! I've seen three types of stroker kits and this is the direction i'm looking to go. I've heard people say to build the car from the ground up and stroking the engine seems like a great way to ensure that i've got a solid base for a supercharger in the future.

suboption #1 - 306 stroker kit - why would someone do this? increase the engine 4ci???? Makes no sense to me but i'm new.

suboption #2 - 331 stroker kit - I've been told this is the most common. Perhaps because after doing other mods (intake, fuel injectors, SC, O2 sensor) if I stress the engine i could just stroke it to a 347????? That seems like a good option. Increase HP, big beefier parts, and some room for error!!!!

suboption #3 - 347 stroker kit - Just go all the way and then the HP might be enough to where i don't need the SC at all. I've been told that this is the extreme and puts undue stress on the block. If this fails am i looking at a new engine. A lot of people have chimed in that at this point dropping a 351 in is a better option.


Okay let her rip! Also i hear a lot of about intake mods but i have yet to see any examples accept port and polish. It seems pretty simple and cost effective. Just need a detail oriented eye! Thanks for the help all!!!!

 

Well first off, horsepower is quite addicting. I don't think you can really have too much of it. With that said, all your options will work fine. A supercharged 302/306 will make good power. This goes the same for a well built 331 or 347. Note: A 306 is not a stroker. It is a 302 bored .30 over-quite standard when rebuilding a stock short-block. You can bore a stock 302 up to .60(310)

I have done all the options listed above. My favorite for speed is my Vortech'd 331. It's fast, comfortable and has excellent driveability. For a fun street cruiser, the nicely built 347 N/A gets the nod. Good lope, good power and fair driveability. You can not really go wrong with any of them. However, know that is is going to cost money, moreso if you decide to stroke the 302. Because GT-40 heads and an E-cam won't cut it on a 331 or 347. Best of luck!

 

With a 347 stroker you can have as much power as you would have with a 351W but have an engine that about 60-80# lighter. This wieght differance would be on the front wheels BTW.

 

I didn't realize that i would need a new cam and heads with the stroker kit. I thought it came with pretty much everything. That might put things on hold for a bit. Is there any downside with going the 347 instead of the 331? I see a lot more 331 cars online and only a couple 347s. Will i need an upgraded intake or fuel injectors with the stroker kit?

 

Im also debating this, apparently boosted 302s and 306s tend to be more reliable than fully built strokers, i've read several complaints of parts braking when you go 347 or 408 strokers. I guess it depends on who builds it but the concensus is the more power you put down the more parts break.

 

It's all about your building ability and the quality of the parts you combine. I just finished a very nice 347 build and on it's first time out, a valve spring broke. The bottom line is, when you build a fast car, stuff is going to break. If you're going to build a stroker, go for the 347 and never look back.

 

347 is the way to go if you are even going to mess with a stroker.
One other thing, what ever kit you use you are going to need it balanced with the flexplate/flywheel and harmonic balancer that you are going to use.
I really don't know how the story of the cheap/easy stroker motor came about because it isn't.

 

I am not really sure how a boosted 302 would be more reliable than a properly built stroker. From my own experience, it would be opposite. If you go the stroker route, as others have mentioned, go 347. 16 extra cubic inches for free; can't really go wrong.

As for building a cheap stroker? Sure you can! Just don't expect it too perform too well!