Thread: Need some help with sbc 350 set up

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im trying to put together a sbc 350 and im having trouble with cr's dcr's in relation to the camshaft I want to use. Ive heard everything from "no it wont run on pump gas" to " ive ran 12:1 on pump gas" tbh my ears are smoking and im at the point where a guy might sit in his garage drink beer and throw hammers at it. Not really but i am frustrated and cant continue with the build until i get this sorted out. sooooo this is what im working with..... bought a goodwrench 350 in 08 im the only owner so crank rods and flat top pistons are as they came when i bought it. i bought a set of aluminum 64cc heads 160 202's 190cc intake runners and a howards cam retro hyd roller intake/exhaust 264.6 268.6 lift 485 495. the engine is in a 1978 chevy K20 pickup, sm465 manual trans, np205 transfercase 410 gears 6" lift on 35" tires. I use it for farting around town but mostly for long hauls with a 1500lb drop in camper. with onboard water and all gear total weight with the truck 7K to 7500lbs. Anyone care to take a stab at it? Or suggest a good throwing hammer?

Let me clarify, I'm being told by a local speed shop that this set up won't run on pump gas due to high compression. I also know that you can back off timing and make it run on pump gas but that's defeating the purpose. From the calc's I've done dynamic comp ratio is around 9:6:1 but I have know idea how that compression will react with pump gas under a constant towing load. Just don't want to grenade the engine with predestination

Thanks for your input Denny. The engine is not in the truck, I pulled it out and I'm using measurements to calc the compression ratios. So 9:6:1 is cranking or dynamic compression maybe slightly less from different variables. I don't want to put this thing together and have to run it on race fuel. Maybe I'm overthinking it.

Welcome to CHR!

I like the Howard's retrofit cam kits and it sounds like yours is appropriate for what you're building. I wouldn't hesitate to run 9.6:1 with premium fuel - especially with aluminum heads. Use Felpro 1003 for .041 thickness, bolt it up and drive it like you stole it. If you want, throw a can of octane boost in the tank before fill up to give you a bit of comfort.

PS - We've all been at the "...throw a hammer..." stage. Better to have a cup of coffee or if you prefer, a cold beer!

Good luck and let us know what you come up with.
Glenn

And - I'd set the initial timing at 8-12 degrees, depending on how she starts - 12 would be fine if she starts up well (especially when warm) if not, back off to 10, then 8 if necessary.

I'm assuming that you know about the different length push rods, cam button, different distributor gear. (I believe Howard's retrofit cams have an excentric to drive the fuel pump rod - but check to be sure).

Let us know how it goes,
Glenn

Thank you denny and glennsexton for your replies. Im going to put it together with what i have and "Drive it like I stole it" hope the camper stays on it lol. ill post some pictures when i get it done. From what ive read on this forum everyone likes to see pictures so ill try not to disappoint. Just give me some time and ill get em up.

Welcome Aboard. Angry78K20. Good to see you here. And yes. we like pictures! LOL

Thank you 30_40. And Glenn, I've been running the Holley sniper efi for the last year so no mechanical fuel pumps. I have the efi dual tanks with in tank pumps and diverter valve. And the sniper is paired with a hyperspark distributor the sniper controles the timing. But I can turn it off for initial start up and set static timing.

And yes I know about the different size pushrods, I bought a whole topend kit. Fully assembled heads matching dual plane windage intake, true 1.5.1 roller rockers. The kit came with an adjustable pushrod tool also.

Originally Posted by Angry78K20

And yes I know about the different size pushrods, I bought a whole topend kit. Fully assembled heads matching dual plane windage intake, true 1.5.1 roller rockers. The kit came with an adjustable pushrod tool also.

You're doing this right - you'll have a noticeable difference in pulling power as well as the 3500-5500 RPM range. Take her for a romp without the caper and you may be surprised at your 0-60 acceleration.

Originally Posted by glennsexton

You're doing this right - you'll have a noticeable difference in pulling power as well as the 3500-5500 RPM range. Take her for a romp without the caper and you may be surprised at your 0-60 acceleration.

Yeah im excited to get it together, i know im not going to be blistering pavement with it lol. I just asked myself what am i really going to be doing with it. so i purpose built it for torque and hauling in mind. dont get me wrong I firmly think that all rear tires need to be punished severely on some pavement at any given time, just not with this build. I already talked to the wife about a 2wd squarebody big block project. Well she shot me down, told me i haven't even finished the one i started. Haha she's right, but thats how a fella starts to break em down, one chip at a time.

Well in the nearly 48 years I've been married one thing I have learned is,

"...listen to your wife..."

And may I add, "YES DEAR"

well she's russian, irish, and mexican so on a good day she's like a tornado in a trailer park haha. {Slowly looks over shoulder} and yes theirs alot of "yes dear's" 3 kids 24years together. happy wife happy life. anyways...Ill be starting to put it together today or tomorrow. Everything looks good on the lower end, the engine has low miles so a quick hone new rings and back together she goes.