I hv a 1970-73 400 CID. I looked up the casting number and it said 265 hp stock. The motor is currently stock still and runs great. I do not want to bore it out for no reason. I want about 400 hp and 450 ft-lbs of tourqe. What heads and cam can be installed to get me closer to my goal. Any help is great and kinda low budget btw
CK5
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400 sbc build
- Thread starter Codyscee
- Start date
it needs a bore, .030 over more than likely, which makes it a 406 IIRC
everything should be freshened up if you are expecting to make any power with it
it also depends on whether you have any smog requirements
everything should be freshened up if you are expecting to make any power with it
it also depends on whether you have any smog requirements
A set of Vortec heads (drill the steam holes), a Performer RPM intake (vortec pattern) and this cam http://www.summitracing.com/parts/sum-k1105/overview/make/chevrolet. Install a 700 cfm carburator (a Q-jet works well), with a set of 1 5/8" long tube headers and you will easily meet your goal. Set the timing at about 18-20* initial with about 36-38* degrees total by about 2600 RPM.
Make sure to check the clearance between the valve spring retainer and guide at max lift, they are usually ok to .490 lift but not always. Make sure to use lots of break in additive in the oil when you break in the cam, use a good 15-40 oil with a ZDDP type additive with every oil change to keep the cam and lifters happy.
Make sure to check the clearance between the valve spring retainer and guide at max lift, they are usually ok to .490 lift but not always. Make sure to use lots of break in additive in the oil when you break in the cam, use a good 15-40 oil with a ZDDP type additive with every oil change to keep the cam and lifters happy.
Skip it. Find a newer 350 block. Build a cheap roller 350 and be money ahead.
Martin
Martin
Find me a factory roller 400 block with a one piece rear main seal.
Martin
Martin
You'll lose 50 HP and 50 ft.lbs though.He could give the 400 to me.............ya, get a 350
Meh, if you want big inches build a big block. Power is over rated.
Martin
Martin
Idk. For the little money I have into my 408... I love it, and a 350 doesnt even compare.
You could build a nice roller 350 much cheaper than a roller 400.
Martin
Martin
Why does he need a roller though??
My flat tappet 408, with summit 1103 cam, new pistons, ground crank, roller rockers, arp studs, and all new bearings with fresh bore and seals etc cost me $1200.
And this motor serves me plenty well.
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My dads got a vortec 454 in his burb...
My 408 has much more balls.
My 408 has much more balls.
He said vortec headed 355 OR a 454.
Martin
Martin
I'll play... I've driven/had quite a few 350's and have yet to find one that will move a truck the way a 400 will. I found my '70 400 in factory 265HP form liked it, bored it .030 and stuck a Comp 260 in it, better. That gave me proof that don't follow cam card reccomendations for a 400, they like more cam. So I had to try more and put a small .484/.498 lift roller in it. That's fun but I know I will give it more somehow/sometime. I LOVE to hear people say they don't like 400's, cuz that makes them cheap for me to pick-up.
I don't dislike 400's. I dislike 2 piece rear main seals and flat tappet cams.
Martin
Martin
Okay, I can understand that... especially the flat tappet. A Crane cam cost me a rebuild on my 454.
depends how an engine is built. I have built a pretty hot 355 for dirt track at would eat 383 406 and 421s all day. To make the same hp with less cubes you need to move more air ie spin it harder. So by the same token the 400 is good because it has more cubes to make more hp down low it is head restricted right out of the gate. If you want power better start with a good head. I only have one nonroller engine anymore and it has bigger ford lifters. I just like BBCs because even the worst head is better than any sbc head from gm.
