Fox mustang 5.0 to 351

What would you do

  • Try to fix the 5.0

    Votes: 2 25.0%
  • Adapt a 351w EFI

    Votes: 5 62.5%
  • Risk another junkyard 5.0

    Votes: 1 12.5%

  • Total voters
    8

Scott 303

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Hi everyone. I have a 1990 Mustang, had a 2.3 4 cylinder. I saved up and got a wrecked rusted 5.0 car and swapped the 5.0, 8.8, T5, got all the wiring done, took a year to finish and now the engine has a knock. A friend will sell me a good running 351w EFI for $500 but I don't know how to adapt it to my 5.0 fuel injection. The local u-pull has some Ford F150 pickups, one should have a 5.0/302 and engines are $320

Would you use the running 351, take a chance on another 302 from a wreck, or try and fix the knocking 5.0 in it now? Keep in mind I am on a real tight budget compared to most around here.

Thanks

Scott
 

Lead-Farmer

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I don't believe anyone still has one that does not have a LS in it. In all seriousness I would probably get a Explorer 302 from the junkyard for a couple hundred and be done with it since you already have everything for a 8.2 block.
 
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r1pilot

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Hi everyone. I have a 1990 Mustang, had a 2.3 4 cylinder. I saved up and got a wrecked rusted 5.0 car and swapped the 5.0, 8.8, T5, got all the wiring done, took a year to finish and now the engine has a knock. A friend will sell me a good running 351w EFI for $500 but I don't know how to adapt it to my 5.0 fuel injection. The local u-pull has some Ford F150 pickups, one should have a 5.0/302 and engines are $320

Would you use the running 351, take a chance on another 302 from a wreck, or try and fix the knocking 5.0 in it now? Keep in mind I am on a real tight budget compared to most around here.

Thanks

Scott
I have been there, done that with several 5.0 mustangs. Get the 351. Last time I did this was in mid 90s, so some memory loss... so bare with me.
The 351 is a naturally torquey engine.

I built a 427 stroker from 351W and I have to say I thought it was more torquey than a GM LS7.


351 OPTION $$ cha ching, just thinking least expensive options:

Fuel Rails: All you need to do is widen the fuel rails w/fuel line in center. Obviously, aftermarket rails are better. Lowered motor mounts I believe 3/4" are better and available.

Distributor: You can use the shaft from a 351 and add the 302 distributor components on it for EFI. make sure firing order is same. I forget if old 351s were different. I had a newer roller 351 in mine. a retune can also compensate here for firing order.

Motor Mounts: 3/4" drop mounts are avail.

A/C Compressor or Alternator: I took a 3/4 or 1" wide piece of metal and extended the bracket w/welder. The 302 bracket is too narrow for the 351 due to the deck height of the 351.

Intake: A 302 upper will go on a 351 Lower for most aftermarket intakes. I would just get an aftermarket intake for the 351.

Starter: consider a small one.

EFI: note, stock pcm = 5.0L. A plug up tune is probably needed.

Radiator: get a 4 core or something better.

subframes: That unibody does not stay istraight under power.

Probably lots I forgot been a while..


REAL TIGHT BUDGET OPTION:


Take 302 apart. Probably a set of bearings will fix it....>>>> probably. She has paper thin webbing, but last a long time if run n/a


MAYBE A BETTER OPTION, SERIOUSLY:


LSX. The LS did not exist when I had my car. I wish it had. You can get a cheap one. Don't underestimate even a 5.3L LS.
 

Scott 303

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Thanks for all the advice. I'll look in to the LS idea and see if it can be done on my tight budget. Even the $500 is a stretch now, and I can set aside $100 or $200 every month for the car so the more I spend the longer its off the road for.
 

Scott 303

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What kind of knock?
Take the engine you have now apart before deciding anything.
Sounds like bottom end to me. I had to replace the pulley, damper, water pump and timing cover as the front got hit in the wrecked I bought. The crank snout looked fine and it turned over easy but maybe it took too much of a hit.

That's good advice to take it apart now. Its the one thing that won't cost me any money. Thanks.
 

lumen8

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Thanks for all the advice. I'll look in to the LS idea and see if it can be done on my tight budget. Even the $500 is a stretch now, and I can set aside $100 or $200 every month for the car so the more I spend the longer its off the road for.
The LS swap really can depend on how you go about it and how much you can do yourself. for example if you want to stay EFI or use a carb...and if EFI, you are willing to use a junkyard ecu and loom, and strip off the stuff you dont need, which is probably the most inexpensive way. Ive done that myself a few times now.

Then you still need to buy hp tuners or similar though to tune it.

The stuff can add up real quick if you start buying everything new, and using aftermarket ECU's

I'd be tempted to go 351W but you'd need to figure out how to tune it.

Ironically the LS ECU can run windsors also (and other engines, people have run everything from clevelands to BBC's and mopars with them)

 

Scott 303

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Thank you for the information. I've been working on pulling the old 5.0 and will tear it down. Selling what parts I can salvage might even get me a couple hundred dollars towards the next engine too.
 

STR-LGL-70

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Thank you for the information. I've been working on pulling the old 5.0 and will tear it down. Selling what parts I can salvage might even get me a couple hundred dollars towards the next engine too.
Have you cut open the oil filter? That's where I would start if you think it's in the bottom end.
 
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