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Discussion Starter · #1 ·
I have a stock mid 70's 350 in my '56. It has stoock heads with a 4 barrel intake and a Q-jet carb and dual exhaust. Runs ok I just wanted to get a little more power out of it with out a completed teardown right now..Will putting a dual plane edlebrock intake give me more hp? Should I change outthe Q-jet? Just looking for some cheap ways to get a little more hp with more torque...
 

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I would keep that qjet. Send it off to Mountain to get jetted and rebuilt if needed. If you have the stock egr type intake dump it. Your heads are your biggest issue. 72-76cc smog heads
 

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HP costs $.

I don't know about cheap, but IMO the first three areas to address are spark, exhaust, and air cleaner.

Install an MSD or other brand ignition amplifier, and a good set of spark plugs and wires.

Then off to the exhaust shop or internet for an appropriate diameter exhaust system with free flowing mufflers, probably in the neighborhood of 2", but not too big for a stock 350.

Last, free flowing air cleaner, appropriate size.

:anim_25:
 

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Discussion Starter · #4 ·
Heads: can I rework the ones I have or should I just buy new ones?
I already have a 2" dual exhaust with cherry bombs so that should be good...Is there really a differnace with MSD ignition?
 

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Light the fire.

...Is there really a differnace with MSD ignition?
Yes. Multi-fire ignition makes a seat-of-the-pants improvement for most cars, in terms of performance and fuel mileage. Multi-fire spark boxes put ten times the energy to the spark plug, by "ringing" the spark over several degrees of crankshaft rotation, instead of a single wimpy spark, insuring the air/fuel mix gets lit.
 

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Heads: can I rework the ones I have or should I just buy new ones?
I already have a 2" dual exhaust with cherry bombs so that should be good...Is there really a differnace with MSD ignition?
There are some decent castings in the early 70s like 487, 993 or even 882, by the late 70s its 624s, probabally the most crack prone SBC head ever made.
 

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a good set of headers

will improve the hp.
but they need to be small tube, 1 5/8 primary's.
I'd keep the Q jet, they can flow up to 800cfm,
a performer intake will accept the Q jet.
and yes ignition will improve start up, idle, and all around perf,
all together the mods will provide a noticeable improvement.
BUT...........
its just a matter of time ,before you will want more HP ,LOL
then its heads, cam , etc.
 

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Always use to make ne laugh when someone pulled a Q-jet and installed a 600 Holley or even worse Edelbrock carb and thought they were gaon9ing something.
 

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Tubs.

BUT...........
its just a matter of time ,before you will want more HP ,LOL
then its heads, cam , etc.
Just call the local chassis shop and make an appointment to get the car back-halved. It all boils down to traction, and you'll need the big meats eventually.

:call2:
 

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maybe some headers and an h (or x) pipe. :)
 

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You cant run a very big cam without modding the Q-Jet. They don't like to idle in gear (auto) with a low vac pulling cam. I myself like Q-Jets. I have built a few that performed very well with the help of a few books. I've been looking for a non computer controlled Q-Jet to build for a couple months. I need one of late 70s era for a 78 442 I've got. You could mildly port your heads to clean up the casting crap and then gasket match the intake manifold. That would give you a few exta horses. Nothing to sneeze at but its cheap power if you got a die grinder and a couple rotary bits. Don't use a bit with close teeth on aluminum though, it will clog the bit.
 

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I have about 50 q-jets rat holed away, the can be run with large cams with correct power piston spring no different than an old AFB in this regard.
 

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Discussion Starter · #14 ·
I have dual exhaust but there is no X or H pipe..does it make more power with an x or h pipe or without??
 

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I have about 50 q-jets rat holed away, the can be run with large cams with correct power piston spring no different than an old AFB in this regard.
WITH THE CORRECT POWER PISTON SPRING is the key words here. So they do need to be modded none the less. To any person with no Q-Jet experience this could pose a challenge. Every time I try to give advice here, I get a responce from someone trying to make me look stupid. This is getting old USA-1. We seem to always butt heads so I will no longer try to give advise or help someone here with a problem or question . I guess YOU are the resident expert on everything but it is funny that I never see any pics of you doing any work or building of anything.
 

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Discussion Starter · #16 ·
good advice about porting the heads, Hafrod. Thats the kinda thing i want to do. Make some extra power without spending a ton of cash...of course after I sell a couple of my other projects I can spend spme cash on a big block and such..:burnout:
 

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Your heads arent worth anything (assuming they are matched and stock) If you you spend that much time on smog heads you mine as well just buy a nice set of used heads off ebay that are ready to go. Telling you, they are restricted and low compression. The work you would do wont be worth it, not without a piston change. Id get some 64cc heads or 416 305 heads with 1.94 valves.
 

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You cant run a very big cam without modding the Q-Jet. They don't like to idle in gear (auto) with a low vac pulling cam. I myself like Q-Jets. I have built a few that performed very well with the help of a few books. I've been looking for a non computer controlled Q-Jet to build for a couple months. I need one of late 70s era for a 78 442 I've got. You could mildly port your heads to clean up the casting crap and then gasket match the intake manifold. That would give you a few exta horses. Nothing to sneeze at but its cheap power if you got a die grinder and a couple rotary bits. Don't use a bit with close teeth on aluminum though, it will clog the bit.
I havent had too many problems with q jets myself. EVERY Carb needs tuned per the engine. Nothing beats a q jet for MPG and performance when done right. I just switched a holley 750 to a jet last year on my bbc and I gained 5 mpg. It was worth spending 200 with mountain man to get it right and still cheaper than a new carb
 

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WITH THE CORRECT POWER PISTON SPRING is the key words here. So they do need to be modded none the less. To any person with no Q-Jet experience this could pose a challenge. Every time I try to give advice here, I get a responce from someone trying to make me look stupid. This is getting old USA-1. We seem to always butt heads so I will no longer try to give advise or help someone here with a problem or question . I guess YOU are the resident expert on everything but it is funny that I never see any pics of you doing any work or building of anything.
Too funny from the guy who has repeatedly challanges my ability. You do not even need to remove the top of a Q-jet to change the power piston spring. Every carb Holley, Edelbrock, Q-jet must be tuned via springs, power valve etc to perform properly on a non stock application. No I am not an expert, but after 40 some years of building street and strip cars I know enough to tell when someone clearly is not one.
 
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