Got a free 6-71 Dyer. Need info to put on my 454

[DarKnight]

Got this 6-71 from dad. It spent a few years on his 355 sbc.

I have a Stock replacement 454 with oval ports iron heads, 4-bolt stock bottom end, hydraulic " R.V. " cam the previous owner had no info on, crane gold-series roller rockers.

i know i need to get a BBC intake for it, but i just want to make sure the motor wont bust under pressure and how much it can handle.

Any thoughts, advice and opinions are greatly appreciated.

this is for my 72 montecarlo. trans is 700r4 custom built with 2200 torque converter

[DarKnight]

test

[GetMore]

Do you know what compression ratio you are currently running?

[Fast01]

If you can research the engine a little more, that would help. You say it's a replacement 454. A lot of the GMPP replacement big blocks, if not all, have forged cranks, rods and pistons along with very low compression (<9:1) which would be a great starting point for a blower and boost friendly. As far as how much boost you can run, it's all dependant on your scr, state of tune, fuel type etc. All in all I think, if done correctly, it'll be a blast to drive and have that "aura" that only a big blower sticking out of the hood can bring! Oh yeah, I love those 1st gen. Montes!

I just saw you have a 700R4....kiss it good bye. It will never hold up under anything other than street cruising. I don't care how it's built. Ask me how I know. Also, if it's not a 12 bolt car, the 8.2 will scatter like leaves as well.

[DarKnight]

actually, this is my daily driver :)
no races for now. i'm mainly thinking of putting this supercharger on just for fun. i don't really need it. but it's free other than a new manifold and hood.

the trans should hold up since it's not being raced. the rear end is a stock 12-bolt 2.73 (don't hit me) that came with the car, but that will be upgraded also.

as for the motor. i think this was your basic 454 you put in your K3500 pick up when the old one died. just a crate replacement, no frills, peanut-port headed big-block

i got this motor from a guy a year ago. it was in his rotting 71 chevy kingswood. the car started to rust away but the motor had only been in the car a couple years, he claimed only 10k miles on it.

from the research i did, i found out its a Gen. V motor

[DarKnight]

forgot to mention that i believe the c.r. is 8.5:1. i only use 91 octane or better in my cars.

[DaviRotten]

Mos def need to change out that rear end gear or its gonna be a dog.. shove a 3;73 or 411 in it and call it a day.

[DarKnight]

well, i'm thinking 3:08 to 3:55. still a daily driver after all and like to keep some of the fuel mileage

[69camarokid]

well, i'm thinking 3:08 to 3:55. still a daily driver after all and like to keep some of the fuel mileage

...seriously?
Its a supercharged 454 and your worried about gas mileage... hahaha:hammer:

[DarKnight]

Well, i do want a balance. no, i dont expect gas milage. but this is a heavy cruiser. it does highway duty from south to north florida from time to time.
i know i have room for better gears though since 80mph = 1900rpm. so a 3.73 is something worth considering.

but i just wanted to make sure the motor would hold up ok and maybe get some insight on how tough a stock big block is

[Fast01]

Keep your boost in check (5lbs.) and stay out of detonation and you'll be fine. I'd consider getting some kind of boost referenced timing retard to be sure you stay within a safe timing limit.

[DarKnight]

yes, definitly underdriving this one.

slight speed bump though
Dyers never made a intake for the v6-71 lowrise blower for a big-block. anyone know of a company that does make them or can fab one up

[sporter]

Plenty of Pontiac 455s running quick with 3.08's in the rear with only 500 ft-lbs at the rear wheels. I think a 454 with a 6-71 will have at least 650-700 ft-lbs at the wheels. Sounds like a good choice for a fun daily driver to me.

[modern-muscle]

Hey if you need a manifold let me know Bobby Dyers live a few blocks from us and we get good deals through him.

[DarKnight]

Thx for the offer John. But Dyers said they would have to make this manifold custom for this application not to mention new pullys. the manifold itself would be $1250 and around $300-$500 for pullys.

Does that sound right to you? its way more than i could put into it. i could almost get a new setup for a few bucks more. i really just wanted to see if we could make the parts i have work

[modern-muscle]

It's a bit out of line from them but I will talk to Billy and see if I can work something out for you

[Zanie]

Oh wow, A V6-71!! Four bolts holding the blower on the manifold, right? My buddy had one on his 57 in the 80s. Gary Dyer
was the only guy making small block chevy manifolds for that blower and he only did it for about 8 -10 years or so. I've never seen a V6-71 intake for a big block. Making that blower work is going to be a MAJOR PITA.
Mass produced (Wieand, BDS) big block 6-71 manifolds are about $400, You'll need a custom manifold for the V6-71 bank on that.
Do yourself a favor and sell the complete small block set-up and find a complete 6-71 for a big block. You can find a BB 6-71 priced right, because guys are going bigger these days 8-71, 10-71, 14-71 due to the large displacement Big blocks available.

That 454 you have probably has cast pistons, so nothing over 5 lbs of boost for you.
The rest of a stock BB is plenty strong I ran a 2 bolt main cast crank, 3/8 rod 454 under my magnacharger (twin blower) for 10 years with 8 lbs of boost, problem free.
Good Luck!
Dan