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camaro_dude15

I need an engine

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Great read guys and awesome story bowtie. Kinda the same way I am just never had the knowledgeable people around to learn from.

 

All this talk about v8's is making me want to start ordering parts for my ls6

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All this talk about v8's is making me want to start ordering parts for my ls6

It makes me wish my Chevy wasn't in cali still >_< My dad is going to haul it over sometime this year. Can't come soon enough.

 

 

IMG_0317.jpg

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If you can do a newer style electronic controlled engine do up a 6.0L chev. They are dirt cheap and have thousands of aftermarket parts available. You can make pretty big power out of them on a budget build.

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If you can do a newer style electronic controlled engine do up a 6.0L chev. They are dirt cheap and have thousands of aftermarket parts available. You can make pretty big power out of them on a budget build.

:withstupid: Don't bother adding another dirty carburetor V8 to the streets :rolleyes:

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so dr bowtie you think i should pick a bigger cam?

Yes, 242 intake duration is too small for a 408. Would be great on a "hot" 351 though.

 

Cam choice really depends on your heads, but for duration on a 408 I'd choose an aggressive ramp rate intake lobe in the high 250 range @ .050. Lift will be based on the heads cfm, but around .600 will be tamable without going to crazy expensive springs. For an all motor engine that wont see nitrous or boost, you want between 107 and 110 LSA. Numerically lower LSA is what also gives you that nice chop at idle, and will be shift your powerband higher in the rpm range. Bad for boost though, since it will bleed through the exhaust valve on the compression stroke due to the high overlap.

 

SBFs are not reverse cooled, so your CR needs to be modest to run on pump gas. I would stay around 11:1, unless you are building for E85 or race gas. To do that you will need to mill most aftermarket heads down (and I don't recommend those heads anyway, which I will explain why shortly). Depending on your deck height you could run a 60 cc combustion chamber with flat top pistons w/ -5cc valve reliefs, and a .030 compressed head gasket to keep your quench in the safe zone for an NA build (~.035). You don't want too low quench (<.030) because of piston slap, and too high quench will cause detonation at even modest compression levels. Not sure what the standard deck height on an SBF is though, since I'm a Chevy guy.

 

190cc intake runner wont be enough cylinder head to feed a 408 at high rpms. I suggest at least a 210cc casting, with 275+ CFM. As a very rough rule, Potential HP = 2 x Heads Max CFM.

 

I also highly suggest a good single plane intake...avoid dual plane intakes like the plague, and don't use a ramjet style intake unless its been worked/raised with tons of plenum volume.

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didnt you see the parts i listed, this will be an efi engine.

Noted that you want to run an HV pump. Be very careful with your oil pan choice - an HV pump can and will suck a pan dry, causing all sorts of issues. If you want to save money, there are companies that can baffle and weld in kick-outs to a stock pan for increased capacity and prevent sucking the pan dry.

 

I have seen it happen MANY times, and I really suggest a standard vol/pressure pump. Those high volume or high pressure pumps actually ROB performance, and are only meant for tired old engines or ones assembled with wider bearing clearances. A fresh engine build does not need nor want HV/HP oil pumps.

Edited by Puck

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Yes, 242 intake duration is too small for a 408. Would be great on a "hot" 351 though.

 

Cam choice really depends on your heads, but for duration on a 408 I'd choose an aggressive ramp rate intake lobe in the high 250 range @ .050. Lift will be based on the heads cfm, but around .600 will be tamable without going to crazy expensive springs. For an all motor engine that wont see nitrous or boost, you want between 107 and 110 LSA. Numerically lower LSA is what also gives you that nice chop at idle, and will be shift your powerband higher in the rpm range. Bad for boost though, since it will bleed through the exhaust valve on the compression stroke due to the high overlap.

 

SBFs are not reverse cooled, so your CR needs to be modest to run on pump gas. I would stay around 11:1, unless you are building for E85 or race gas. To do that you will need to mill most aftermarket heads down (and I don't recommend those heads anyway, which I will explain why shortly). Depending on your deck height you could run a 60 cc combustion chamber with flat top pistons w/ -5cc valve reliefs, and a .030 compressed head gasket to keep your quench in the safe zone for an NA build (~.035). You don't want too low quench (<.030) because of piston slap, and too high quench will cause detonation at even modest compression levels. Not sure what the standard deck height on an SBF is though, since I'm a Chevy guy.

 

190cc intake runner wont be enough cylinder head to feed a 408 at high rpms. I suggest at least a 210cc casting, with 275+ CFM. As a very rough rule, Potential HP = 2 x Heads Max CFM.

 

I also highly suggest a good single plane intake...avoid dual plane intakes like the plague, and don't use a ramjet style intake unless its been worked/raised with tons of plenum volume.

 

 

uh i was planning on 428, 408 if i am tight on cash and cant afford an svo block

 

 

oh and if you can find a dual quad intake for a 351 thats single plane and not overpriced, let me know, lol, i looked

Edited by camaro_dude15

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didnt you see the parts i listed, this will be an efi engine.

I know I just wanted to make sure you didn't get tempted any any point. My friend had an EFI 351w in his '88 bronco so I knew it wasn't :evilgrin:

 

good luck though dude, I still haven't built any motors or done anything that deep. (yet)

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uh i was planning on 428, 408 if i am tight on cash and cant afford an svo block

 

 

oh and if you can find a dual quad intake for a 351 thats single plane and not overpriced, let me know, lol, i looked

Why in the world would you run a dual-quad intake? :blink: IMO those are for show cars or pure drag race big-blocks. They are terribly expensive, and have no real benefit to a smallblock. If you want EFI like you are planning, a 4bbl TB is 500-600 bucks a pop...thats over a grand just for throttle bodies! For dual 4bbl carbs (which I don't recommend), its even more expensive and a PITA to dial in.

 

For a pretty cheap intake setup I would run a Supervictor EFI since they pop up all the time on racingjunk for cheap, often already fully ported and ready to go. Also an Accufab 4bbl throttle body is 100 bucks less then a wilson and is a popular, high quality piece.

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Why in the world would you run a dual-quad intake? blink.gif IMO those are for show cars or pure drag race big-blocks. They are terribly expensive, and have no real benefit to a smallblock. If you want EFI like you are planning, a 4bbl TB is 500-600 bucks a pop...thats over a grand just for throttle bodies! For dual 4bbl carbs (which I don't recommend), its even more expensive and a PITA to dial in.

 

For a pretty cheap intake setup I would run a Supervictor EFI since they pop up all the time on racingjunk for cheap, often already fully ported and ready to go. Also an Accufab 4bbl throttle body is 100 bucks less then a wilson and is a popular, high quality piece.

 

 

becuase i really really like fast's ez efi, it was a dream to work with, and its full on ready to plug and play duel throttle bodies, on there site they say one of there throttle bodies are good for under 500hp, two are for over 500, this system is so easy to run duel tb's i think its worth it, 3k for your whole fuel system, pump included, dual throttle bodies, pcm, and a programmer, every thing i need, but as been with my theme through out this thread, everything depends on my job situation, if i am tight in cash, i will probably go with a holley carb

 

 

oh and i missed the thing you said about the high volume oil pump, i should be fine with it as long as i get a high capacity oil pan, and i have an oil accumulator around here somewhere, that should help

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