Building a 400 SBC question?

[poolman]

I'm running a stock 400 now with tons, 43" 205 ect. On propane,, I'm thinking of putting some more life in it. Running it in a light weight juggy but really thinking about a buggy chassis. So either way what's the best upgrades for a sbc on propane, I don't have a problem running another mixer, I'm sure I'll need to.

 

[Elliott]

Lots of Compression, get a custom ground cam from bullet, and make sure you've got some good flowing heads. 400's are pretty easy to make run very well

 

[YOUNG]

For the amount of money that you will put into that old school 400 you could have a 350hp LS motor with fuel injection for less money.

I would REALLY think about swapping to a LS motor. Once you do, you will never look back.

 

[Eddyj]

Until a minor electrical problem keeps you from wheeling. Keep it simple.

 

[sparepartsdave]

to keep it cheap, use stock length rods, the shallowest dish pistons you can find as an oem piston and use small chamber heads.You'll be surprised how much compression you will build with a 400. If you aren't going to turn many rpms, vortec heads will be fine. IF you want to spend some money and make bigger power, go with 5.7 rods, flat tops, and small chamber heads with good flow numbers, use a cam one size bigger than most recommendations, the extra cubes of a 400 tend to soak up cam profiles.

 

[Jhouser]

I would go with 5.7 or 6.0 rods a small dome piston and a set of Profiler heads and a healthy Hyd roller cam or even a mid range Solid roller with dual mixer's and let it . You can make a ton of Torque with a SBC 400 compared to a 350.

 

[kushKrawlin]

For the amount of money that you will put into that old school 400 you could have a 350hp LS motor with fuel injection for less money.

I would REALLY think about swapping to a LS motor. Once you do, you will never look back.

I wouldn't. My 400 sbc has plenty of power, and guess what the best part about it is.. About 3 wires and that bitch screams!! Also there's just somthing about gas in somthing that spends the majority of its time bouncing around, on its side and upside down that scares tha piss outta me. I guess if ya have a lot of experience building motors and putting them in maybe.. But if ya already have the motor in the rig, unless you have a ton of money to piss away you would be retarded to get a new motor. My has never been taken apart, Not to mention I have no clue really about building a motor.. But a voodoo cam, lifters, headers, (my mind just went blank) and my **** has PLENTY of power.. And with the propane it's pretty much like feel injected when cranking. I wish I knew more bout motors... Do you guys that can put motors together, tear one apart when you buy Rick just to make sure The parts are actually in there?? I always wondered this, cause I dam sure would. It kills me not to know exactly what all is in my motor.. But whatever is in it I like it. What I do not like is electrical nightmares, that I see time and time again with 6.0's and such.. I love the simplicity of the motor.. Run that bitch! If it's in your rig already than you know, if not you will know that you might need to make sure to keep it cool, had over heating problems like crazy when I got it, so I took the fan off motor, and ditched the lil pee wee electric fan up front and put dual fans off of a caddy my buddy gave me, and now it stays around 190-200... They have 5000+ cfm's or so.. On one mixer for me too.. Just need to put on my msd box I bought dam near a year ago... Not having a rev limiter is prob not great for me. Would love to ride in a bone stock one just to see difference. Like I said I have no clue about motor stuff, But about 80% of the people walk up to my rig , when it's runnin , and the first thing they say is "dam that sounds good, what cam is in it?" And my reply as always is " man I wish I knew" haha. I'm gonna get my buddy to do compression test just for the hell of it..

 

[muddinmetal]

to keep it cheap, use stock length rods, the shallowest dish pistons you can find as an oem piston and use small chamber heads.You'll be surprised how much compression you will build with a 400. If you aren't going to turn many rpms, vortec heads will be fine. IF you want to spend some money and make bigger power, go with 5.7 rods, flat tops, and small chamber heads with good flow numbers, use a cam one size bigger than most recommendations, the extra cubes of a 400 tend to soak up cam profiles.

Dish?

 

[Elliott]

A lot of people say ls swaps are cheap, I don't think they've ever done one. There is a lot of parts to be had to make it work right

 

[poolman]

I'm not interested in a ls swap, I just want a little more power, just trying to see what I could do to increase hp,torque for a grand or less. I'm going to keep it in for the hardline ride and fall crawl, after that I'm considering pulling it out? But I ain't gonna throw any more than that in it. I'm not a motor guy so would it be worth doing? Or would my increase not be worth the money?

 

[scrowexj]

I'm about firm believer in a 400. I have one in a 65 Chevy show truck. Mine is .40 over with flat tops, good cam "can't remember the speck on it " dart aluminum head's and long H rods I would say you get most out of a good cam and heads more than anything. But I don't run propane so don't really know what works for that.. just my. 02 but if they talk you into running something different and you get rid of the 400 and it's standard bore I would like to buy it

 

[Jhouser]

Best Bang for your buck in my opinion would be Roller Cam.

 

[sparepartsdave]

Dish?

they never offered flat tops stock in a 400, only dish, if you want to go budget, you need to run oem type pistons, even with a dish piston, a 400 builds compression pretty easy. .200 dish pistons(assuming 8 cc dish) and 58 cc heads get close to 11-1. If you want to spend extra money, then go flat tops. stay away from 6 inch rods in a 400 unless you have money to burn, even with 5.7 you may have to run a reduced base circle cam

 

[payne97]

Rebuilt it custom ground cam & springs with vortec heads and you can use the serpentine system off of it good power and cheap