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5.0 and 3.8 compatibility?


spottedsquirl

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Hey everyone, long time since I've been on here. I really need to know how compatible a 5.0 is to a 3.8 as in internal parts; pistons and rings, rods and such. I'm trying to get my truck back on the road as a daily driver and save fuel. Any advice welcome thanks
 


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adsm08

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Pretty much none at all. The stock 302 has a 4 inch bore and a 3 inch stroke. The 3.8L by comparison has a 3.81" bore and a 3.39" stroke. Those are significant differences.

The two engines aren't even remotely related. The 302 is a stroked version of the 289, which replaced the Y-blocks, which were Ford's first OHV engines.

The 3.8 was stolen and then (poorly) copied from the GM 3.8L.
 

spottedsquirl

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Thanks for the reply. I wasn't hoping too much, just an idea I had.
 

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They do share the bellhousing boltpattern if that does you any good. Like if you have a v8 swapped truck with a bad engine.
 

spottedsquirl

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When I blew the rings out on the 3.8, I just swapped it with the 5.0 and used the same tranny.
 

ALMACK

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They do share the bellhousing boltpattern if that does you any good. Like if you have a v8 swapped truck with a bad engine.
I was reading somewhere that a 3.8 bellhousing can be used on a 302 but you must use a 164 tooth flywheel from a F150 in order for the starter to line up correctly ?

Just asking around to confirm...
 

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I was reading somewhere that a 3.8 bellhousing can be used on a 302 but you must use a 164 tooth flywheel from a F150 in order for the starter to line up correctly ?

Just asking around to confirm...
I don't know anything for sure, but with what I do know about it I would think a 157 tooth would be a better fit. The 164 tooths are huge.

I don't dick with 3.8s though, so I am not sure.
 

ALMACK

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I don't know anything for sure, but with what I do know about it I would think a 157 tooth would be a better fit. The 164 tooths are huge.

I don't dick with 3.8s though, so I am not sure.
I have both a 3.8 BH and a 5.0 BH from 95 Mustangs.

The starter location on the 3.8 is further out from the centerline of the crank.

So I kinda believe the larger f/w would work.

Not sure if the 164 would fit inside the b/h
 

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82 3.8's leaked oil because the only gaskets they used were head gaskets-everything else was RTV and that was before RTV was up to the task. Once the leaks were fixed we didn't have any trouble with 3.8's until they reworked the coolant flow for front wheel drive applications, then all hell broke loose. At the new model school when the 3.8 was introduced they told us it weighed 4 lbs more than a 2.3. If you're happy with the 3.8 rebuild it and save yourself some work and money. A v8 swap would mean new headers/manifolds, modified exhaust, probably radiator, and always things you don't expect. I'd rather have a v8 but you mentioned a budget.
 


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