This is topic 351 swap - advice & pointers please in forum Tech Talk at Northern California Ford Owners  .


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Posted by hard jokur (Member # 3360) on :
 
I'm looking at upgrading my tired 302 in my 91GT. It's basically a daily driver, maybe an occasional stip run.
I'm hoping to be able to use most of my 302 bolt-ons as well (is this possible?) like my EQ length shorties.
What about head selection (can I use 302 heads or do I need 351 specific?? Intake (the main concern is lower intake) ?? Cam (I'm pickin up a B303 cam this weekend)?? Serpentine belt and factory accessories?

Above all else must pass CA smog...

Any one that has done this can you give me some pointers??

Thanks
[Confused]
 
Posted by stoauto (Member # 2803) on :
 
you will NOT be able to use the headers off of your current 302. summit racing sells EVERYTHING you need. give them a call.
 
Posted by JohnB (Member # 969) on :
 
Here ya go..

351 Swap info

[ July 17, 2004, 07:50 AM: Message edited by: JohnB ]
 
Posted by hard jokur (Member # 3360) on :
 
Great info...

I'll be running it as EFI.
I also have a Mach1 style hood (not installed yet), will this provide enough clearance?
How is the B303 cam for this app?

[ July 17, 2004, 08:17 AM: Message edited by: hard jokur ]
 
Posted by FasterDamnit (Member # 442) on :
 
The B will be a very torquey but run out of steam before 5k. More displacement means you can run more cam w/out worrying about idle problems.

FYI- IF you get a smog tech that knows what he is looking at, the 351 will not be legal (unless you drive a '93 since the Cobra R of that year was a 351). Any smog techs want to coment?
 
Posted by hard jokur (Member # 3360) on :
 
SMOG was brought up before, after reading the thread, I was under the impression that as long as you used the smog equipment for your year car.

so my 91 would have to retain 91 smog equip. The after market goodies (not many) I have so far have CARB numbers.

Good point about that cam, I'm not one of those wind'em up drivers so I "should be okay" then again [burnout]
 
Posted by JoeT (Member # 298) on :
 
quote:
Originally posted by FasterDamnit:


FYI- IF you get a smog tech that knows what he is looking at, the 351 will not be legal (unless you drive a '93 since the Cobra R of that year was a 351). Any smog techs want to coment?
that's not my understanding, my understanding is that any 79-95 mustang can be a legal 351 car if you work with a state smog ref because you can in general swap any engine of a later year into a car so long as it was manufactured *after* your car was. so basically take a '95 crown vic 351w smog system into your car and you're good.

BTW since when does a '93 cobra R come with a 351?

However, most people I have talked to in CA admit that they # of gas-station smog techs that can identify a 351 vs a 302 are few and far between. It's probably easier to smog a stock looking 351 than it is to smog a 302 with a blower in terms of the dirty looks you'll get from the smog guys.


For instance other swaps I have researched are the LC2 (turbo buick) into an '88 RX7. Last year of the GN was '87, so it's technically illegal to do that swap. Find a '87 RX7 (or earlier) and you're good.

So with a fox there's 2 strategies: claim the engine is from a crown vic (safest) or a lightning/F-250/E-250 (smog equipment may not be identical between passenger cars and trucks though), and that the engine is newer than your car.

Or... just try to look as stock as possible and the smog guys will generally never know. Even a cowl hood is so common on mustangs they probably won't think motorswap by seeing a cowl hood. I bet 95% of cowl-hooded mustangs have a stock 302.

just my understanding...
 
Posted by 88DroptopGT (Member # 2535) on :
 
The only way they know the smog techs will know you have a 351w swapped is if they run the engine block number or pull out the ruler to check the 9.5" deck height (which they won't).

My advice is making the engine look as stock as possible and have all the smog equipment to eliminate all questions. I have seen people do legit smogs with 331 and 351w EFI swaps without any questions. Those engines all were h/i/c'd but looked stock and had all smog equipment. In fact, I've read a post where a certains owner 331 D.S.S stroker had cleaner readings than his old 165k 302 he replaced.

The trick is to make the engine look as stock as possible and have paperwork verifying carb e.o #s for the aftermarket parts that you do have. It's not that hard if you don't have radical setup.

BTW: the '93 R did NOT have a 351 in it.
 
Posted by 87 Saleen (Member # 1549) on :
 
93 cobra R doesn' have smog equipment either.

They didn't let Ron of Mustangs plus register his in California becuase of that.
 
Posted by JohnB (Member # 969) on :
 
Yes, 93 R's have smog equipment. The car couldn't be legit for sale to the general public if it didn't. And no, they came with 302's. Same engine as the standard Cobras. About the only differences was a cheesy de-gas system on the radiator, a cooling radiator for the PS, no back seat (with delete), 5 lug setup that was slated for the 94's, radio/power equip group delete..and you got red, crappy Tri-bars..That's it.

I'm willing to bet..you drop a 351w in, NO run-of-the-mill smog tech will know the difference. I say go for it!
 




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