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Discussion Starter #1
Today I started up a 5.0 i pulled from an explorer in March 2016. I don't know if its the split exhaust banks / cam / etc. -but- I have NEVER heard a motor sound this good!

My first project car motor was a stock 283- reminded me of a late 90's grand prix 3.8 at higher RPM - warble warble warble / bear in mind it was stock with a 500cfm 2 barrel

Next was a 350ZZ4 (replaced 283 above)- typical SBC sound / Flowmasters. Sounded nice but got harsh about 4-5K. Solid motor though

Next was a 350L82. I rebuilt it and added a 214/224 @ .050" flat tappet with vortec heads. I think the ZZ4 sounded better (the Flowmasters helped). I do run it through a full 2.5" exhaust though - nice rumble

But this 5.0 in the cobra? WOW. I built the motor with a trick flow TFS1 cam 221/225 with GT40 heads. Stock rods/pistons, new rings and a Autolite 4100 clone carb from summit. Nothing special in my mind -but- it sounds MEAN.

I think the more oversquare bore (vs. a 350SBC / 351W / -eg- longer stroke) plays a role in this because you need to rev the shorter stroke motors to get the air through them. It rev's quick and sounds nasty. The mains on the 5.0 are smaller too (lower bearing speed / helps with rev's)

Obviously you won't get the power of a 347/351/363 SBF out of a 5.0 -but- you get some serious bang for the buck that mates nicely to this car. I got the motor for $242 from a salvage yard and spent another $1498 to complete it. I did NOT bore it, only polished the crank, honed the cylinders and verified everything was still in spec. Nice thing about the late model windsors are the blocks are high nickel content so they don't wear as quickly (rings were low tension from the factory too). I could still see crosshatch after 189k miles! There was some cylinder taper, but well within spec. On the heads I replaced all the valves / springs / etc. (full rebuild) - didn't regrind the valve seats but lapped the new ones. Starting in 97, all explorers/mountainers came with GT40/GT40P heads and parts are plentiful and cheap (flow very well too up to .5" lift)

The two negatives I see with this approach
1- You add a fair amount of time to your build (I likely added 5-6 months)
2- You'll bite your nails until you start it the first time because of the extra unknowns that come with a high mileage donor as you assume extra risk.

Time will tell if I made the right decision, but so far its looking GOOOOOOD!
 

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FFCobra Fanatic
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Nice! A lot of the fun is in the build, mostly that first start.
 

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Discussion Starter #4
My love of gm in the build is 2 fold-

1. Simplicity - coil on top keeps the engine bay simple and it sparks up to 70000 volts. One annoyance with a gm distributor on a Windsor block - you greatly limit air cleaner options and the cap is biiiig/tall and of course, in the front. I ended up purchasing an offset base and I had to turn a unique spacer to clear the fuel rails. I hope (fingers crossed) I don't have a hood clearance issue and I have to go to a thinner element.

2- cheap (70$) - its a china special from eBay. Summit carries variants -but- (as you stated) - no steel gear there. I found mine on eBay. I almost switched the used cam position gear from the explorer with the new one for extra "is it really steel or China steel" insurance. Going to check after the shakedown to see if it's wearing.

I think msd sources much if their lower buck offerings from the same Far East sources - likely the same place.

If I was building a race motor, I likely wouldn't have gone this route but for a street motor, I see lots of value with hei

Thanks for the comments/compliments
 

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I built my own 5.0 as well, very similar to yours with stock '95 Mustang short block from the donor, rebuilt GT40p heads from a wrecked Exploder (I did some very mild port work to them but otherwise stock rebuild), E cam (similar in spec to TFS stage 1), and GM ignition. Only difference in my ignition is that I used the Duraspark distributor controlled by an HEI unit rather than a whole HEI distributor. As you say, definitely added time to my build (I also converted to carb'd intake, fuel pump, timing cover, water pump, etc which adds time) and a little nerve wracking on first start but big grins when it all works out. I don't think I've ever had it above 3k RPM yet though, I don't live in a neighborhood that would appreciate that amount of noise lol.
 

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Discussion Starter #7
Thanks guys - flaircraft - great minds think alike ;) / sounds like we have the same motor. How's it go when you are on the gas? I'm still adjusting the carb and have 500 miles or so ahead of me before I kick it down (and that's only after I license it!)
 

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Also what helps the engine rev fast is the flywheel and clutch weight/diameter = rotating inertia. You should hear my 363ci, with 13.5 to 1 compression and a 5.5" triple metal disk clutch!

 

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I started with a 1988 Mustang 5.0 engine, went with aluminum Brodix heads with 1.94/1.60 valves, stock 4" bore & 3" stroke, Eagle internally balanced forged crank, OEM forged pistons, OEM rods, ARP hardware, Engle cam, solid mechanical lifters, steel roller rockers, and aluminum flywheel with a King Cobra clutch. I'm hoping for a fairly quick-revving engine that's reliable and has a vintage sound to it. For now it's only got 44mm Weber IDFs but will either put 48s on it when I get bored with it or will swap it out for an LS to take some weight out of the car.
 

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That sounds like a nice build / were the Webers tough to tackle/you happy with the end product or are you switching to an ls because you aren't?

I have an ls in my future too / for my corvette though - you can find the lq4 blocks pretty easy/cheap (although I think those are typically iron so you might not save much on weight).

That king cobra clutch looks mighty nice too (small/compact) - I have a cheap 11" on mine / we'll see how it does. I added 295 radials and hopefully it can handle a warm day on hot asphalt :)
 

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So far I haven't run the engine much so I still need to figure out the tune. It wasn't hard, just have to pay attention to details. One thing that seems to be mentioned by all of the guys familiar with Webers is that the linkage is the key to it running right. The linkage cannot have any play in it. The turkey pan I built around them make it tough to get to the mixture screws near the base of the carbs. I'm also trying to figure out what I'm going to do for an air filter. The turkey pan will have bulb-seal around the top of it to seal against the nose and I'd like to cut a hole in the bubble on top of the nose like the originals have. But I'm thinking that I'd like to 'glass some rails onto the underside of the nose to slide a thin air filter into but I need to find such a filter.

I'd like to go with an LS because I keep reading that, along with more hp, you get a nice drop in weight with the all-aluminum engine over the iron-block Windsors. Plus, Peter Brock has an LS in his personal Coupe and, if CS had had his way, all the Cobras would have had Chevy engines in them so it just seems "right".
 

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Thanks guys - flaircraft - great minds think alike ;) / sounds like we have the same motor. How's it go when you are on the gas? I'm still adjusting the carb and have 500 miles or so ahead of me before I kick it down (and that's only after I license it!)
I'm at about the same stage you are, just got my title and haven't tuned the motor for anything other than idle yet so can't really get a good impression on how fast it is. I know the engine could use a much quicker advance curve than what's in the stock 5.0 distributor but haven't had the time to check the base curve and then re-curve it yet. Then it's on to mixture tuning, then after that I might see what it can do... of course by seat-of-the-pants it'll probably feel underwhelming since I'm used to my shifter kart lol.
 
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