stick an 850 on a single plane intake and turn it 7500. no need for dominators and tunnel rams.

I ran dual 850's on my engine but my engine also isn't for street use. I'm switching to a dual 4.1" toilet system this winter.

How much of an induction system depends how you want to use the car. A tunnel ram on a street car is a bad choice. Tunnel rams are designed for 4000+ rpm and street cars rarely get that high. I spin my 540 to 7200 and have a 6000 stall converter so after I launch, the rpms never drop below 6000 until after the finish line. 13:1 compression on alcohol.

A single 850 on a Victor intake will do fine on your engine. That's what I used when I ran a 469 CID. I think the rectangular port heads may be too much for your engine. Some oval ports will be better or keep the rectangular port heads ans bump the compression up higher to around 12 and get a bigger cam.

sounds like a mismatched combo that you're trying to put together. weren't you talking about having a bigger crank and making a 496? and now you want to build smaller cubes, have too big of heads and want to slap on a small cam and a high rpm tunnel ram with too low of compression? It would be a dog on the street and track. Go look up other similar builds off different websites compared to their ETs and you'll get a better idea on how to build up a big block.

yeah man, 13:1, bigger solid roller and a single plane with an 850 would be BAD

well, the reason for going 468 is due to me having a forged 4" crank, I've got the 4.250" crank its cast steel eagle i picked for 150$ brand new, the heads i picked up were 650$ freshly reworked, so its either those, or my 1968 model 215 casting large oval, but there closed chambered heads and really aint work crap... as far as tunnel ram was an idea i was chunkin around the room, just curios on other peoples input. i could got 12-1, 740" 270 @.050 cam and a 5k stall converter, but the price of race fuel on a dual purpose car is not practical... especially if im gonna drive 4 hour to pigeon forge to the rod run... if i knew where to buy e85 in bulk i would do it and try running proform's e85 carb... seriously, the heads couldnt flow no more than 320 cfm's... the right intake and carb set up should be fine, i would think.

The heads on my 540 are only 310's. they're a little small for the engine. 345's would be better but I'm already running in the ET range I want to run at so I don't need bigger heads.

as far as how to build a big block, i think i have enough knowledge on how to build up a big block, If i had the money then i could do it right, but i got to work with what i got.... i just got bored and started lookin at tunnel rams, Ya i know a lot of people do it and they run like **** cuz the carbs arent synchronized right, are most likely too much carb, the cam being small, ya i know, but i alrady have it, done over cammed a 427 with it, and with 10-1 compression on a 468, it will be pretty well border lined. the rectangle ports is all i got, gonna use em, whether there too much or not........

But I do appreciate all advice i get from ya'll dont get me wrong, just bashing the subject isnt what im lookin 4....

we're not bashing the subject, just being real. you asked us what we thought, we gave you our educated opinions. if you're planning on using those cylinder heads, you NEED more camshaft...

geez give a guy an honest opinion that it's a mismatched combo and he bites my head off about "bashing the subject". If you had "enough knowledge on how to build up a big block" this wouldn't even be asked on a forum, you'd already know the parts are mismatched and you should sell off some of the components to make a good working combo before you build it and are unhappy with the results.

This is pretty close to the setup my buddy is running with a tunnel ram and a pair of 660 center squirters.

468
10.5:1 compression
GM rect. port open chamber heads mildly ported
ATI flat tappet cam (yes ATI the trans people)
Lift: 658 int 665 exh
Dur. 274 int 278 exh.
CL 106
Turbo 400
8" ATI converter flashes to 4800
5.13 gear
14 x 32 tires

Best ET 9.83 139mph in 3400lb 67 Chevelle. Shifts at 7200 and goes through at 7800

I know several people running this same cam and all run real well and deadly consistant. I think lunati make it for ATI to thier specs. I know you said you had a cam already but just thought I would give you a proven setup as an alternative.

a 1050 will run faster on this set-up, I tested both and discussed with carb shops all said the same thing, dominator is faster than the 850....tunnel ram more difficult to tune..Rob

if you want to rev a BBC that high get a 396/427 3.76" stroke forged steel crank.
Bore the 454 block .100" over for a 447ci motor.

Get a solid roller with 262 265deg@.050 in 270+ish ex on 108LSA lift is your friend on a BBC.
Crane #138811 or #138831

Use Edelbrock street ram or Weiand hi ram for your square port heads.
Use two Edelbrock 1407 carbs. (easy street tuning)
Get a 9" 4500 stall converter. big tube headers.