I'm going to be building a what I hope will be a pretty decent running 400, reason being is me and my dad will be building a 62 Special Gasser to run , and they hit you hard with weight as your cid goes up, but to be competitive I'm going to need to run a 400. I'm planning on 12to1 or better, big cam, hogged out heads and Offy with 2x4s. What's been your guys results with a 400 if you've ever built one? Is 550hp obtainable with the above ? Not worried about TQ it will geared to at least a 4.30
If your block is thick bore to 4.3125- 455 . Ask Gary Paine . Flat tappet cam 308s . The Stage 2 makes 600 less the heads you could be there . old TRW stage 2 Pistons stock rods also .
Am I correct that you're limiting yourself to 400 cid max? The inexpensive way to do this is to stick with the '67 - '69 400 block's bore, but finding one that would clean up well enough and not need an overbore is going to be a challenge. On top of that, the bore is small enough that the larger Stage 1 valve sizes are a no-go performance-wise, and with higher valve lifts you could even have valve-to bore clearance issues, something I've heard possible, though I don't remember hearing anyone report it. Your next options start to cost more because you'd be destroking in order to get a larger bore to help the heads. Devon
Yea I'm limited to no more than a 430cid, one because you can't use an engine that wasn't available b4 1970 and two because the bigger the engine the more you have to weigh. I was thinking a nice set of small valve heads with a big cam to crutch them with a load of compression, to be honest 500hp would work need to run 6.40's to be competitive
That sounds like a relatively inexpensive way to go, a healthy 400 block should to go to to the 430 (and less) bore easily. You'd just have to look at piston availability for bores at 4.1875" (original 430 bore) and maybe smaller, or choose a custom piston. Devon
I would use a much more readily available 430 block, bore it to 4.250 for good ring availablity and then de-stroke the crank to control your CI... a .150 destroke builds a 425, and building a "reverse 494" would get you to 414ci combo. Custom pistons are required for anything your building here, and we have rods ready to drop in for a number of de-stroke combos. Just optimize the deck height with custom piston CD. HP only limited by your imagination and budget.
Question is do they go by the casting # to tell what size the motor is or do they pump it? If they go by numbers, the 400 is the way to go,
Use a 430 block like Jim said but only bore(actually just hone) to 4.195" where there are decent rings available, here is a quick Summit search; https://www.summitracing.com/search/part-type/piston-rings/bore-in/4-195-in?PageSize=100 Using 5.4L Ford mod engine rods that are 6.657" long; https://www.summitracing.com/parts/sca-6665754/overview/ A couple more different mod rod options; https://www.summitracing.com/search/part-type/connecting-rods/connecting-rod-length-center-to-center-in/6-657-in?N=4294925198+4294879970&PageSize=100&SortBy=DisplayPrice&SortOrder=Ascending&keyword=5.4L connecting rods If you want to keep your rod ratio closer to factory with a 3.740" stroke using a set of the mod rods .010" under bearings for a 413 CID economy build with more $$ left over for head work if that is allowed? If you want even less cubes you can go to a .050"(IIRC they make them up to .060" under) undersize mod rod bearing to go to a 3.700" stroke for 409 CID! To get the cubes down even more, a Nailhead crank with 3.640" stroke can be made to work in the 430 block with block spacers and new main caps. With this combo the crank can be stroked or destroked .050" or left where it is and use BBC rods of your choice, or the ones made to fit a BBB with a custom or customizable piston of your choice. With the N/H standard stroke you would net 402 cubes or 396.95 CID with the N/H crank destroked .050"!!! Of coarse the piston would be getting WAY tall, but using the Mod rods and a destroked N/H crank and you could even get the cubes down to 380.366 CID with a .200" destroked N/H crank!! Using the soon to be released 6.800" BBB 482 drop in rods the above would also be doable using the sbc undersize bearings available. With BBC rods and the N/H crank you could get them in a 7.100" length that will help make the pistons lighter if that's the way you prefer as well. Sounds like a fun project, wish my dad was into this stuff when he was alive. GL Derek
Yea, My Dad and Quain have known each other for 40+years and a couple of his friends run them so he wants to go build one here's our canvas, trans will be a Hightower 4speed
I reread the rules and actually at 8lbs per cubic inch a good ole 464 is fine 6.40s will be no problem , you get weight breaks for dual carbs, and a few other things so it would need to come in at 3600ish lb , most everyone runs small cid stuff but as always I'll go against the grain ha
That will make an awesome gasser. You guys going to run the whole circuit? If you do, I'll come see you when they run in Montgomery, AL.
Bingo, I was going to suggest this, back in the 70's I used a 430 bored enough to take advantage of the bigger stage1 valve head then de stroked to meet the ci requirement, thing reved like a small block chevy. Would be awesome in a light car . gary
Prices vary from shop to shop but that is in the ballpark for having a crank stroked, never had one destroked but should be the same? Derek
Offset grinding is the same procedure, regardless of which side of the journal you do it on. Cost varies depending on how much you offset it, and where you live. Up here, my guy over at Crank Supply in MPLS charges me about $250 to offset the rods .050 AND to index the rod throws, which insures proper timing/placement of each throw. An important process when you start changing the stroke on any crank, and it should not be overlooked. To go all the way to a .250 offset, it adds about $100 worth of grinding time. JW
With a .020" over 400 block and a standard stroke Nailhead crank the cubes would be 378. Would need to use BBC rods though so the rod journals would need to be taken down to 2.200". Can't use the rods made for a BBB 455 when using the N/H crank because the width of the rod journal is a bit wider for the N/H crank requiring a rod with a wider big end. Forgot about the N/H rods being wider than the 455 rods by .039" per rod so .078" wider per rod journal from my previous post so the new 482 soon to be available won't work with a N/H crank. N/H rod width = .967" BBB 455 rod width = .928" BBC rod width = .990" There should be good rings available with a 4.060" overbore as well. Wouldn't be the first time someone used a N/H crank in a BBB block, Finishline Performance has before so they didn't have to wait for Moldex to make one for them, I think that's how the story goes? Derek
