Two engine options, which for 650hp?

[65ShelbyClone]

The 351W is a brute for bottom end strength, the journals are larger than a big block.

The mains are only larger than that of an FE. 351Ws and 385s both have 3" mains. The early 351Ws are fairly strong, but the later roller blocks tend to fail 100-200hp higher than a 289/302.

I'm pretty sure the new Genisis block is like one of the top dogs for FE motors now.

As far as I know, the Genesis is the only aftermarket FE block available. The ironic part is that a rebuildable(and often sleeved) original side oiler 427 bare block goes for about the same as a Genesis aluminum. Which would you rather have?

Built what Y-block? You don't hear about that every day....

No kidding. My old man has a 4v 292 sitting in the yard with a Fordomatic stuck to the back. It came out of his '57 2-door 300 that coincidentally, is now getting a(dual quad) 390 GT engine and Toploader .

 

[brianj5600]

The mains are only larger than that of an FE. 351Ws and 385s both have 3" mains. The early 351Ws are fairly strong, but the later roller blocks tend to fail 100-200hp higher than a 289/302. .

I'm curious if you have ever seen a broken 351 block. I hear numbers thrown around, but never seen a cracked 351 block. 5.0's are easy to find cracked in half, but I've never seen or heard of a cracked 351. Roller 351 blocks fail at 100-200 hp higher than what? Does rpm play into this number?

 

[65ShelbyClone]

There's no concrete number that any block will fail at. For this reason I purposely left a wide window. Many will argue that roller 302s split at 500rwhp, but some have split stronger Sportsman blocks at 450 N/A and stock blocks as high as 650 F/I. Others will say early 289/302s can go higher. This makes a theoretical window of 650-850rwhp for a 351W, although they seem to have issues at the low end of that scale.

 

[Marc_G]

Well, I have been looking around and found a few cheap 351w's. I may just go that route, considering that motor work will be a pain in the ass with a 390. I was just under the impression that since some 67's came with 390's, that under the hood wouldnt be too tight, but I am wrong!
So say I go with a 351w. Probubly stroke it to a 408, can someone with a desktop dyno or sumthin of the sort build me a decent budget motor around 600-650hp. And one other thing, this is a drag race motor, so it needs to be reliable at the strip and thats it, streetable no way, N/A even a bigger no. Probubly a 150 or so shot of nitrous. So if anyone has made a combo or can give me info on a combo of the sort (like what parts, airflow, etc), I would greatly appreciate it, thanks!


Marc G

 

[10secgoal]

I'm curious if you have ever seen a broken 351 block. I hear numbers thrown around, but never seen a cracked 351 block. 5.0's are easy to find cracked in half, but I've never seen or heard of a cracked 351. Roller 351 blocks fail at 100-200 hp higher than what? Does rpm play into this number?

I think RPM has ton to do with it from what I have seen. Both early blocks. The first should had a main girdle. It was in a off road truck and took a nice peice out of the webbing in the block. Hit high RPM's everytime the thing left the ground. The other guy I believe may have had a little hard block. Not too much if he did. Still drove it around the street. It was a 408 that revved to 6800, and ran 5.60's (1/8). He burned pistons quite often, but never broke the block.

 

[RFMustangGT]

Built what Y-block? You don't hear about that every day....

My father has a 55 t-bird. we had a 292 bored .30 over, 312 heads, blue thunder alum intake, MSD distributor, MSD wire, MSD coil, holley 650 carb, sanderson headers, and an orignal holman and moody nascar race cam kit. then we had a toploader 4 speed made to bolt to the back of it. pretty fun car to drive. it's got some god awful low gear in the rear end that just snaps your neck. as much fun as it is we'll probly have something a little bit higher so we can actually drive it on the interstate for long periods of time. motor soul dbe putting out 350hp but it still has a lot left in cause the cam was dail back a little street and plus at teh time we were planning on using the orignal 2 speed. but due to a lack of strong parts for it, we chose a toploader 4 speed.