3v engine savvy guys step in please

[DVEST8R]

I have a 5.4 3v short block sitting around collecting dust and have an idea. I have a very good machine shop and im thinking of having the block sleeved to a 3.7 bore. With a stock stroke/rod legenth im looking at 358 ci. Will likely deck block/heads to compensate for the piston being further in the hole. With the right h/c/I combo can good power be made 7-7500? What power out put could be expected with say 11:1 compression?

 

[skwerl]

What will you do for an intake manifold?

 

[retfr8flyr]

I think it would be much easier to pick up a set of 4v heads. That way everything for the GT500 would work on the setup. With the 3v heads you're going to need a custom intake and exhaust manifold setup.

 

[G.T]

if you're thinking of using that 5.4L Block with the 3V heads.. the only way forward will be a custom sheet metal manifold.. or something out of a F150 :S

 

[Department Of Boost]

You will need some pretty big cams to feed that 358. And ported heads would help a lot too. Making the motor bigger without improving cylinder filling doesn't do a whole lot of good.

You can use any 4.6 3v intake, it will just need some adapter plates. They would be pretty easy to make (with a CNC). I have all the drawings in CAD to be able to put some plans together in no time.

With ported heads, cams, etc I don't see why it can't make 450-460 ish. But it will cost you way more than putting a blower on it.

 

[DVEST8R]

NO adapters exist to make the 4.6 3v intake work?

 

[Department Of Boost]

NO adapters exist to make the 4.6 3v intake work?

No..........

 

[AlbertD]

Not sure if he is still on the forum or not, but Spyder7724 had one of the baddest all motor 3Vs back in the day.

His build thread... http://www.s197forum.com/forum/showthread.php?t=6047&highlight=spyder7724

also... http://www.s197forum.com/forum/showthread.php?t=26603

 

[SStang]

I've always wanted to do a 5.4 3V! I know you said 3V, but if you use the 4V heads, you can use the Boss intake with adapter plates from MMR, or weld some tabs to the heads, to bolt the intake down. I'm not sure if the price of sleeving the block would be worth the price. Could use that money buy a good set of custom cams.

SStang.

 

[BruceH]

Custom pistons with a proper compression height would take care of the .122 in the hole a normal 5.4 is. 1.300" -1.340" would do it I think. There might even be pistons available that are close to that compression height and bore. IIRC some GM motors are fairly close. You could spend some time on Summit and see what's available.

 

[Roush fun]

If you had money for a blower you could pick up the stuff off a roush nightmare

 

[s8v4o]

You will need some pretty big cams to feed that 358. And ported heads would help a lot too. Making the motor bigger without improving cylinder filling doesn't do a whole lot of good.

You can use any 4.6 3v intake, it will just need some adapter plates. They would be pretty easy to make (with a CNC). I have all the drawings in CAD to be able to put some plans together in no time.

With ported heads, cams, etc I don't see why it can't make 450-460 ish. But it will cost you way more than putting a blower on it.

What would a set of plates cost out of curiosity?

 

[Department Of Boost]

What would a set of plates cost out of curiosity?

I would guess $600-750. They would be a "one off". If they were a production unit and I could run 20 they would be about half that.

In theory that could be done by hand (not CNC) for less then $600-750. But they would be "prototype" looking.

 

[s8v4o]

Thanks for the info!

 

[BruceH]

Would there be an issue using a F150 intake? Besides it using a different throttle body?

 

[skwerl]

Would there be an issue using a F150 intake? Besides it using a different throttle body?

Only the minor issue of needing a 3" scoop in order to be able to close the hood.