4" Stroke Crank
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Alright, so if I also wanted to walk down a similar (but not as large) path and create a 395 / 396 LTX via a 4.03 bore and 3.875 stroke, would the special Probe manufactured Ford 331 pistons, crankshaft shaving, and the "in-between" 5.8 inch con rods still be required?
I might choose this set-up vs. the 383 / 388 if it can be done w/o too much trouble, as I've been enjoying my 11 lbs of boost (via my STS) on my stock LT1, but I'm sure one of these days it'll be time for another rebuild!
I might choose this set-up vs. the 383 / 388 if it can be done w/o too much trouble, as I've been enjoying my 11 lbs of boost (via my STS) on my stock LT1, but I'm sure one of these days it'll be time for another rebuild!
The whole idea behind this 408 build is to make stump pulling torque as this will be primarily a street motor. I also have a lead foot like most guys on this board, and occasionally get out to the track. Well a street motor won't cut it at the track so I'm gonna spray a little giggle juice in it and make myself happy
. Plus I think it'll be down right fun to mop a few of the Cobras in the area and tell them they just got stepped on my a damn near 20 year old car.......It probably will be 20 by the time the build is done 
. Plus, how many times can you say that you've seen a 408 LT1 powered car? If Dart had decided to go ahead with their block I would have been holding out for a 434, but sometimes you have to deal with what you've got....... 
yah i wanted to do a 427 or 434 to.i say build the 408, and a k1 4340 4" crank for 750 isnt a bad price at all......i just scrapped a lt1 block 2 mounts ago. and after reading this i had a idea, to gring the pan of the block end to see how much grinding it would take till hit the water jackit.
The 396 ci motor is based on the 3.875 stroke, a 5.85 rod and a piston with a compression height of right around 1.23 give or take a couple of thousandths. All this is based on a deck height of 9.025 which is what factory spec is for a SBC, including the LT1. The 396 offers a slightly better rod/stroke ratio, so it would probably be better suited for an FI build. In the 396 there are no "special" procedures, as in grinding the counterweights, and needing "Ford" Pistons. In fact there are plenty of places to buy 396 packages without much issue at all. Most don't even need as much grinding on the pan rail, so they "may" not need the fill in the block as well.
The whole idea behind this 408 build is to make stump pulling torque as this will be primarily a street motor. I also have a lead foot like most guys on this board, and occasionally get out to the track. Well a street motor won't cut it at the track so I'm gonna spray a little giggle juice in it and make myself happy. Plus I think it'll be down right fun to mop a few of the Cobras in the area and tell them they just got stepped on my a damn near 20 year old car.......It probably will be 20 by the time the build is done . Plus, how many times can you say that you've seen a 408 LT1 powered car? If Dart had decided to go ahead with their block I would have been holding out for a 434, but sometimes you have to deal with what you've got.......
The whole idea behind this 408 build is to make stump pulling torque as this will be primarily a street motor. I also have a lead foot like most guys on this board, and occasionally get out to the track. Well a street motor won't cut it at the track so I'm gonna spray a little giggle juice in it and make myself happy
. Plus I think it'll be down right fun to mop a few of the Cobras in the area and tell them they just got stepped on my a damn near 20 year old car.......It probably will be 20 by the time the build is done . Plus, how many times can you say that you've seen a 408 LT1 powered car? If Dart had decided to go ahead with their block I would have been holding out for a 434, but sometimes you have to deal with what you've got.......Thanks for all the info!
I appreciate this so much more than "Do a search!" as there are only a few members who actually mod theirs internals; most just contimplate it, but for whatever reason (bills, life, divorce, etc...) never actually pull the trigger.
So, go ahead - built that 408, or (if I can be so bold), if you go with a bore of 4.035, you'll create a LT1-based small block 409!
I just thought I'd throw that one out there for your consideration.
Oh, and as for "stump pulling torque" - that's what a Pontiac 421 SD has! Of course, those motors do not rev over 5,500 easily...
Have fun and keep us posted!
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From: burbs of chi-town
Truthfully I'd love to do the 409.....I just would rather keep the pistons as an off the shelf item as opposed to a custom set. If I do ever have to replace something, it's so much easier if they have them already made as opposed to having to make one before I can get it....
I'd love my plates to read
MYFNE409
It'll be close enough at 408.2 Ci......
I'd love my plates to read
MYFNE409
It'll be close enough at 408.2 Ci......
