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Discussion Starter · #1 ·
I have a '58 Chevy Apache. Currently with a Small Block Chevy 350 all stock except Edelbrock Performer RPM Intake Manifold, a Holley 4160/1850-3 600cfm and HEI distributor with new plugs and wires. All this runs perfectly fine. My Father has a SBC 400, I can have if I rebuild (this may be a trade not sure yet). He said it ran great but just started to leak before he swapped it out for a Big Block Chevy. That was 15+ years ago, sense then it has been garage stored waiting to be brought back to life.

So the question. I would say I am on a tight budget. Obviously I want more power! But Can not afford tons of new high performance parts and machining.
Assuming the plan is use the same aftermarket parts listed above and hoping that the 350 and 400 wont NEED to machined and just honed. What is the suggested views?
Rebuild 350 or Rebuild 400? Or bore the 400 to a 406? Or spend more money and try and build a 383?

any ideas or tips would be appreciated.

John
 

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Hiw much money do you have? What are the head castings that you have? Is this just a cruiser or is going to see some strip/dyno time? Your carb is fine for cruising, but is going to give up a bunch a well built 350, let alone a 383 or 406.


A low rpm torque monster is going to be a different build than a 6000+ high hp build.
 

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Yes, how much money you have is really what it comes down to. Just based upon your initial post you've stated you have a 350 that runs perfectly fine. There's a 400 out there that you may not know a lot about until you bust it down. A 383 option has been thrown out there and you say you are on a TIGHT budget. That being said, I'd stick with the 350. I don't know what your goals are other than you want more power and you should be able to get it out of the 350. I'm building a 383 right now and there's nothing cheap about it so if $ is tight, 383 prob be the last option.
 

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Discussion Starter · #4 ·
Well not much money, I would say the Boss (wife) would only be ok with $200-300. The 350 has not been checked out much. I replaced the intake manifold (found 3/4" holes drilled through to the exhaust cross over, any idea why??) The valley looked ok, but I'm feeling that it should be rebuild as well.

Overall plan for the truck is between a daily driver and a street rod. By far no drag or street racer here, just wanna go fast and cruise.

I found some old forums with similar questions, and like I was thinking everyone was saying use the 400 more cubes and then improve cooling system. And to bore it out to 406. Which maybe I could budget in, if we can find a trustworthy Machine Shop around here.
 

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Well not much money, I would say the Boss (wife) would only be ok with $200-300. The 350 has not been checked out much. I replaced the intake manifold (found 3/4" holes drilled through to the exhaust cross over, any idea why??) The valley looked ok, but I'm feeling that it should be rebuild as well.

Overall plan for the truck is between a daily driver and a street rod. By far no drag or street racer here, just wanna go fast and cruise.

I found some old forums with similar questions, and like I was thinking everyone was saying use the 400 more cubes and then improve cooling system. And to bore it out to 406. Which maybe I could budget in, if we can find a trustworthy Machine Shop around here.
$2-300 is not going to get it done, unfortunately. If your current 350 is running properly, then consider looking for some upgrades to it. A set of long tube headers would be the 1st place to start as they can go from one engine to another. But a decent set will eat your budget, and they should be worth another 20-40hp ahead of where you are now. Other than that, you'll need a couple thousand dollars, at a minimum, to build a reasonable street motor from scratch.

Asked previously and yet unanswered, what head castings do you have on your current 350 and on the one that you have access to?
 

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X 2... $200-300 isn't going to get you a rebuild which usually includes a re-bore and new pistons at least... best you could hope for is a 'going through' making sure all parts are good and servicable if you can do that yourself... maybe stock bore new pistons and mild budget cam/lifters/springs...

As nailhead mentioned, headers and dual exhaust are often the best performance bucks spent... usable HP recovered over a single exhaust setup per dollar spent... Try some inexpensive Summit 1 5/8" short or long tube headers... If you already have stock Rams Horn style iron exhaust manifolds, they don't flow too badly used with dual exhaust pipes/mufflers system...

http://www.ebay.com/itm/Chevy-SBC-3...haust-Headers-w-2-5-Center-Dump-/351717419280

https://www.summitracing.com/parts/sum-g9060

https://www.summitracing.com/parts/big-11500flt

Need to find out what 350 and 400 engines... Chevy 350's came 360 grossHP down to 125 netHP... Gen. 1 bathtub chambers heads, Gen. 1 swirlport heads, and Gen. 1.5E Vortec heads versions... 400's came 265 grossHP down to 175 netHP all bathtub heads... grossHP to netHP ratings change came about 1971...

There's no sense in putting a bigger camshaft in the lowest HP 350's and 400's, the stock cam was prolly too big for the compression ratio and resulted in horrible MPG...

Different pistons to bring the compression ratio up (if needed) (~$85 - $350) and a mild performance cam/lifters/springs (~$135 minumum) can bring either engine up into ~350 - 375 grossHP range... 14's in 1/4 mile...

Chevy SBC 350 Flat Top Pistons Moly Rings Kit 030 355 | eBay

https://www.summitracing.com/parts/sum-k1103
 

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Discussion Starter · #8 ·
So my Father has two SBC 400
a 3951511 4-bolt main
And
a 3951509 2-bolt main
Either one I can have but he is suggesting the 2-bolt because the 4-bolt was leaky and smoking. The 2-bolt starred up perfectly 10yrs ago.
 

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two SBC 400
a 3951511 4-bolt main
And
a 3951509 2-bolt main

Either one I can have but he is suggesting the 2-bolt because the 4-bolt was leaky and smoking. The 2-bolt starred up perfectly 10yrs ago.
511 4 bolt earlier '70 - '72 and maybe more powerful with usable 9:1 compression ratio, despite 2 bbl. carb...

509 newer '73 -'81 lower power with lowish 7's:1 compression ratio and 4 bbl. carb., but stronger block...

Guess I'd pull a head off each and check cylinder bore wear...

On such a tight budget, if 511 usable bore wear, I'd put in new gaskets and bearings and the 4 bbl. carb./intake off the 509...

Or stick with the 350 if better condition, depending on which 350 it is...
 

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Discussion Starter · #10 ·
JohnIIIreed;3757721 two SBC 400 a 3951511 4-bolt main And a 3951509 2-bolt main Either one I can have but he is suggesting the 2-bolt because the 4-bolt was leaky and smoking. The 2-bolt starred up perfectly 10yrs ago.[/QUOTE said:
511 4 bolt earlier '70 - '72 and maybe more powerful with usable 9:1 compression ratio, despite 2 bbl. carb...

509 newer '73 -'81 lower power with lowish 7's:1 compression ratio and 4 bbl. carb., but stronger block...

Guess I'd pull a head off each and check cylinder bore wear...

On such a tight budget, if 511 usable bore wear, I'd put in new gaskets and bearings and the 4 bbl. carb./intake off the 509...

Or stick with the 350 if better condition, depending on which 350 it is...

That's what I as thinking pull a head or both of each inspect and rebuild the better one for me. And I'd use the Edlebrock Performer RPM and one of my 4 Holleys
 

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Discussion Starter · #11 ·
But does anyone have a idea why my old Performer Intake would've had huge hole's drilled into the exhaust cross over? The motor was/would be sucking inert exhaust gas with no restriction. Why would someone have done this?
 

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But does anyone have a idea why my old Performer Intake would've had huge hole's drilled into the exhaust cross over? The motor was/would be sucking inert exhaust gas with no restriction. Why would someone have done this?
I can't picture what your describing, so how about a picture.
 

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Discussion Starter · #13 ·
So here is my old intake manifold. Found the holes when I first pulled the carb off to rebuild, had no other options to replace it at the time so ran it for a little while, seamed fine. Put the new manifold on and feels much better. But I just can not figure out why the someone would've done
 

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So here is my old intake manifold. Found the holes when I first pulled the carb off to rebuild, had no other options to replace it at the time so ran it for a little while, seamed fine. Put the new manifold on and feels much better. But I just can not figure out why the someone would've done
Power costs more money than you have right now. Leave it alone if it runs well and start saving a few thousand minimum. If you are young, newly married, and struggling financially - you might need to give up hot rodding and concentrate on other more important things.

Don't know about the holes. Seems like that would be a huge vacuum leak unless the crossover was blocked by the intake gaskets. p.s. that's not a Performer RPM manifold - just an old Performer.
 

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Do those holes actually go into the exhaust crossover system? Or into the crankcase and function like part of the PCV setup? As Blazer said, if into the exhaust crossover and it's blocked off, would run OK, but I'd be concerned about the crossover eventually filling up with raw gasoline... And even before that, gas/fumes in the crossover affecting the A/F ratio at certain RPMs...
 

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Discussion Starter · #17 ·
Yes it the holes go into the exhaust cross over, no it wasn't blocked off, yes there was small amount of raw fuel in it when I pulled it off. But the plan is to try and TIG the holes closed, clean it up and sell/trade it away.
 

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Discussion Starter · #18 ·
No one got any ideas why someone would've drilled those holes? I asked multiple seasoned technicians/mechanics and they are all stumped.

And as far as the 350 or 400, I think we'll leave the 350 where it is and get the 400 Running and swap it in later
 
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