To SBC to BBC or not to SBC BBC...

[dirtbag7]

Finally!!! I have been working non-stop for 3 months, no time to work on my "baby..." ( I use that term loosely because I intend on THRASHING my K5)

My dilemma, I HAVE to do something for more power, and I want alot more power... Do I keep the current 350 with the Eddy intake and Holley Carb, punch it out to a 383, cam it up, ya know work it over real good... OR Do I swap it for a good 'ol 454 and work it over?

The tcase is about to become a 205, D60 front, 14 bolt rear, crossover steering, detroit-ish rear, ARB front... probly 4.88's... Mayb 5.10's.... and end somewhere around 40-44" boggers...

My K5 is going to be a goo-slinger... My driving style is high RPM's., my basic driving style has always been "If you got stuck, it's because you didn't hit it hard enough..."

Ps, not sure on the $ amount I'm going to have available for the engine alone because I NEED to do a gear swap first, and since I'm going to be there, why not do the full fledged axle swap...?

 

[toomany]

For running in the mud, go with the 454. You won't need to spin the motor as high with the extra torque of the big block.

 

[Chevy305]

You want high RPM for mud slingin. I'm talkin 5K or more. With high rpm you keep the wheel speed up and thats what gets you through a lot of muck.

 

[dirtbag7]

I appreciate both posts so far, I want to make sure I'm getting understood clearly. I WILL be in the high RPM range, this much I know. My honest question is which motor? SBC or BBC...

 

[76zimmer]

I appreciate both posts so far, I want to make sure I'm getting understood clearly. I WILL be in the high RPM range, this much I know. My honest question is which motor? SBC or BBC...

you talking 6500, or 8000?

thats the difference between BBC, and SBC properly built of course?

 

[onetonbb74]

Id go sbc, there more reliable in the high rpms department.

 

[imiceman44]

Id go sbc, there more reliable in the high rpms department.

Ehem, NO
They are only powerfull in the higher RPM.
Big blocks can take the high RPM much better, it just costs more to build a high powered BBC than a SBC.
If you want to build a reliable engine and not worry about it falling appart real quick, and have the money to put in from the get go, go BBC.
If you have enough to build a SBC and then will have more money to keep patching what you break, because you will break, then go SBC.

 

[Fabrimacator21]

I don't know about BB taking high rpms better then SB's. Sure they can hit high rpms but I don't know about taking them better. The SB will be snappier and lighter and can be built to make BB numbers for around the same price.

TONS of options... You can build a 500+ hp SBC for under 5k and have plenty of rpms... I'm not a huge fan of the BB so I couldn't tell you which would be cheaper but if it were me I'd go SB.

Since I've looked at the gen III sbc's I'll never consider building a gen II motor again. Power is alot easier to make and they do it right off idle up to the high rpms.

A cam and L92 heads and your up at 450+hp. Don't have to stick with FI either. Check out 6.0l's... Stroke them and you've got a 402. If your gonna stick with gen II then I'd go 383.

 

[onetonbb74]

Im sure this is all my opinion, but I just look at the angle of the pushrods in a bbc and tell myself no way I want this engine to rev 8k, even with lots of high dollar parts.

 

[toomany]

You want high RPM for mud slingin. I'm talkin 5K or more. With high rpm you keep the wheel speed up and thats what gets you through a lot of muck.

You ever see a diesel bogging truck?

Not to start an argument, but a low/mild RPM big block motor will work just as well as (maybe better) than a high strung small block. What is the typical powerband of a high RPM motor? Usually not a whole lot on the bottom end. High wheel speeds can be achieved other ways than with a fast motor. Higher engine speeds are harder on parts and cause more wear. Of course this is just my opinion. My mud running K5 has a SBC in it, waiting for the BBC to get built.

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To join the rest of the conversation:

BBC's can be built to turn high rpms. It will cost more money to do so though. You need to invest in good rods, pistions, and fasteners. I would consider a forged crank too, but it's not manditory. You're going to drop some coin for a good set of heads.

I still say go for the BBC. Or build the biggest SBC you can afford. Bigger motors make more power easier.

 

[Fabrimacator21]

You ever see a diesel bogging truck?

Yup... they were usually at the bottom of the totem pole.

 

[imiceman44]

You ever see a diesel bogging truck?

Not to start an argument, but a low/mild RPM big block motor will work just as well as (maybe better) than a high strung small block. What is the typical powerband of a high RPM motor? Usually not a whole lot on the bottom end. High wheel speeds can be achieved other ways than with a fast motor. Higher engine speeds are harder on parts and cause more wear. Of course this is just my opinion. My mud running K5 has a SBC in it, waiting for the BBC to get built.

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To join the rest of the conversation:

BBC's can be built to turn high rpms. It will cost more money to do so though. You need to invest in good rods, pistions, and fasteners. I would consider a forged crank too, but it's not manditory. You're going to drop some coin for a good set of heads.

I still say go for the BBC. Or build the biggest SBC you can afford. Bigger motors make more power easier.

Well my point was that a big block with more meat and bigger internals will take WOT at high RPM better than a SBC can but also the fact that you can get the results running a BBC at maybe 5k will be same as a SBC at 8k, why not do that.
I am the type of guy that overbuilds thing, or if using weak parts I baby them.

 

[Fabrimacator21]

Well my point was that a big block with more meat and bigger internals will take WOT at high RPM better than a SBC can but also the fact that you can get the results running a BBC at maybe 5k will be same as a SBC at 8k, why not do that.
I am the type of guy that overbuilds thing, or if using weak parts I baby them.

Dollar for dollar I'm doubting that.... maybe torque but hp wise I doubt you'd have to string out a sb out to 8k to hang with a bb at 5k.

 

[toomany]

Yup... they were usually at the bottom of the totem pole.

All the ones I've seen have done fairly well, considering how heavy they are. Most have 40"+ tires and have the full turbo/fuel/computer upgrades going on. I've seen them burried up past the tires in some thick goo and spin up all four tires without any problems.

 

[DEMON44]

just picked this up tonight...........


You know ya waaaaaana!

 

[dirtbag7]

OK guys, thanks I guess? LOL... I see ALOT of different opinions here, and maybe I'm more confused than when I started... maybe not... I guess it's going to come down to my personal pref. I just want a healthy, extremely potent, reliable engine. I like to put my foot to the floor once I "ease" into the goop. (I don't necessarily like the thought of my new engine ingestiing alot of water/mud...I hear that's not good 'fer 'em...) Thanks for all the responses tho!