Thread: Quest for 10s 396/402 Big Block build (Big Block Guru's welcome)

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Originally Posted by jerry clayton

a 454 crank is 4.00----I think that in a 396 block you have a lot to grind away for rod clearance
Pistons for a BBC type head in a 396 bore size will be custom for any different stroke---
I suggest you find a different block for a starting point -----------

no its not bad customer built one about 4 years ago club member sleeve 396 . KB makes a hyper piston that made to do just this Jerry .new starting .i know this guy that has a 511.498.496.489. that will sell you one and ship it to your door shake that piggy bank

the 4.000 can be a 454 crank it this point if you used a stock Gm 454 crank or stock replace ment crank you will have a external crank so will need a 454 damper and fly wheel . if you go after market on the 4.000 crank i think you can get one internal cut for the 6.135 stock rod . you have to look in to this i have one at the shop i was not going to use it .i have to see what the counter weigths are cut for what size rod. for moving up to the 4.000 crank should not be a very big deal 366to 427 and 396/402 all use the same stroke crank that is 3.760 or 3.765 so 240 more stroke is not much if you use a cap screw rod and not a threw bolt rod that will help with room . i am not going to say that you will not have to check it and you may want to clean it here not a big deal

Sorry Pat----I know that there are shelf cast pistons, but I was thinking along the lines of custom forged stuff---and Capscrew steel rods would take less clearancing than the stock thru bolt and especially the aluminum rods of yea day--------
I remember back in early mid 70s using tall deck truck blocks with .400 long rods and 454 pistons, cutting block decks way down and machining flats of pistons to get bigger dome CCs---------

Any good brand forged cranks I should look at? I know in LT1s amd LS1 eagle and scat are terrible. I don't know how good they are in older motors

Originally Posted by Bigblock76fbody

Any good brand forged cranks I should look at? I know in LT1s amd LS1 eagle and scat are terrible. I don't know how good they are in older motors

used many scats there fine better then some others out there

We use mostly Scat and Callies---sometimes Scats arrive in an iron reinforced pallet that has to be cut apart to get to them----------

That can be accomplished. Yet=?? remember -you have now traded more weight(basic engine sizes) for the small block so that alone must be overcome . Good heads , big cam & intake is ness. Yet - you must run some high octane race fuel also. High octane(not=pump gas!!) equalls more heat & =more power. must have some 11-1 comp ratio or higher. Seems you =like most of us are trying to build on a budget-thats ok -just remember when ur @ tyhe track there will also be thos that built with big bucks.

i've heard many horror stories of scat and eagle, a guy in charleston sc, has a 355 Lt1 in his 94 z28, broke 2 forged eagle cranks. Went with an Ohio forged crank and no issues. So i wasnt sure of the quality of that brand in the older engines.

Heres a link to the heads Pat, are these the AFR your talking about?
AFR 265cc Oval Port Magnum BBC Cylinder Heads 3610-1 - SummitRacing.com
or these Brodix
Brodix Cylinder Heads Race-Rite Oval Port Cylinder Heads for Big Block Chevy 2061001 - SummitRacing.com
or trickflow
Trick Flow® PowerOval® 280 Cylinder Heads for Big Block Chevrolet TFS-41300001 - SummitRacing.com

I wanted you to take a peak at those flow #s and see which one you think would be good for this build. Im leaning more of AFR because you mentioned it, and everybody has had good results with them. I just wanted to run the other brands by you to see what you thought.

Would this crankshaft fit? it's a 4.00 Callies Callies Compstar Crankshafts BBO425-CS - SummitRacing.com
or if you've got one at your shop that you think will benefit me i could purchase it from you. Im looking for forged because i do want to spray at the track unless you guys don't think i need a forged bottom end. Im only seeing the track maybe 3 or 4 times a year

Sorry to be such a nuisance with a bunch of dumb questions. I'm new to big blocks and learning as i go

Originally Posted by Bigblock76fbody

i've heard many horror stories of scat and eagle, a guy in charleston sc, has a 355 Lt1 in his 94 z28, broke 2 forged eagle cranks. Went with an Ohio forged crank and no issues. So i wasnt sure of the quality of that brand in the older engines.

Heres a link to the heads Pat, are these the AFR your talking about?
AFR 265cc Oval Port Magnum BBC Cylinder Heads 3610-1 - SummitRacing.com
or these Brodix
Brodix Cylinder Heads Race-Rite Oval Port Cylinder Heads for Big Block Chevy 2061001 - SummitRacing.com
or trickflow
Trick Flow® PowerOval® 280 Cylinder Heads for Big Block Chevrolet TFS-41300001 - SummitRacing.com

I wanted you to take a peak at those flow #s and see which one you think would be good for this build. Im leaning more of AFR because you mentioned it, and everybody has had good results with them. I just wanted to run the other brands by you to see what you thought.

Would this crankshaft fit? it's a 4.00 Callies Callies Compstar Crankshafts BBO425-CS - SummitRacing.com
or if you've got one at your shop that you think will benefit me i could purchase it from you. Im looking for forged because i do want to spray at the track unless you guys don't think i need a forged bottom end. Im only seeing the track maybe 3 or 4 times a year

oh bull shit i have more of them scat cranks making more power in things they should not be in scats are not no way shape or form eagle cranks . and i use many of the ohio stuff has this is a open post i not going to blast some of them companys on here but i use just about all of them and some i would never use again . i have used.eagle. cats .scats . rpm,elgins . ohios .compstars .howard. brc. callies some in the shop at the same time ..so some dumb ass thinks they can just drop parts in with out checking any thing cuz they pickup a crank kit ...then cry on the net.. there is allways more to it.... compstar are ok i use them and the mangum when the steam is on i know what they flow have the sheets on the race rites right here were we had them flowed my valve job my bowl work .not posted there numbers the AFR is what chamber size use on this build if you going to spay how much ????? better re think hyper pistons cast steel crank will hold out loner then them pistons will

i had a feeling those AFR's would be the winner for my tax return check

The spraying wont be for awhile down the road, but when the time comes, i'll start off with a 75 shot and work my way up. But the motor will probably be sprayed a handful of times a year. Most of the time the motor will be NA, no spray or anything. Thats why i was debating of going with a forged bottom end or not because i wont be spraying that much. Im sure i can still run 10s all day without a forged bottom end

so was that your 94 that broke the 2 cranks?

No my 94 was stock with headers

I'd bet that the reason the two cranks failed is that they were/were not balanced and had wrong combo of flywheel/flex plate------------

That could've been the issue, im not sure if it's a home built motor or a shop assembled but heres a link to it on youtube

https://www.youtube.com/watch?v=Cqsg...feature=fvwrel