Smog 440 build? Worth it?

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Everywhere says the 509 needs compression, don't use it on a 7.5:1 motor. If you can find some closed chamber heads, that's worth a few points compression. Solid valve train will need adjustable rockers, ball/cup pushrods, and solid lifters. Might want to look into subframe connectors too, at least bolt them in, or better, weld in and weld to floor along the way.
 
Subframe connectors are already welded in. 8 point cage. Traction bars. Etc etc no inner fenders just tubing from firewall to frame. Etc...

Now the 509 was making 370hp 450 torque in a smogger in the first post... Which seems weird to me also
 
70dusterpink said:
Subframe connectors are already welded in. 8 point cage. Traction bars. Etc etc no inner fenders just tubing from firewall to frame. Etc...

Now the 509 was making 370hp 450 torque in a smogger in the first post... Which seems weird to me also
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Weird? How so? We have dyno tests with stock 906 heads, a 509, 7.45:1 compression, with 450 lb-ft @ 3,300 rpm and 387 HP @ 4,900 rpm.

Then 7.85:1 compression, 509 cam, ported 516 heads, 470 LB-FT @ 4,500 RPM and 449 HP @ 5,300 RPM.

Is that more..........or less weird?

You'll notice that when we put closed chambered heads on we gained a whole .4 point of compression.

The 509 isn't the best choice cam for this combination. It just happened to be what we had laying around when we did the dyno exibition.
 
Wow. All that extra hp from .4 increase in compression. Or was it the ported heads... ;-)
 
Just weird you can get that power out of a smog motor when the usual is it needs compression I'll all for it!!

Now what would be the perfect cam for the stock 906 heads?
 
My old combo. 76 440 new rings and bearings. 452s shaved .050. stock valves bowl clean up. Isky 304 525 mega cam [email protected]. weiand xcelorator 850 carb. 4.56 gears. 3500 stall. 3500 lb. challenger. best time 7.46 at 92 mph. Strarted with mopar 484 then 509 then the Isky. Went quickest with the Isky. Don't know why? Way over cammed. But it worked.
 
Taking about my 76 motor and so far this guy lied also missing 4 pushrods and sludged up suppose to be a low mile running when pulled motor.

Ugh I can't win that's twice now I got hosed
 
70dusterpink said:
Just weird you can get that power out of a smog motor when the usual is it needs compression I'll all for it!!
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You can get power from anything to a point. Compression more affects the rpm point of peaks and the overall peakiness of the torque curve, not the peak figures. In terms of your pulling truck you know the rpm you need to maintain wheel speed. Build the engine and gear and convertor the truck to put you where you need to be. For a street car those low compression packages don't make peak torque until 3300 or higher. How often are you cruising around there? You'll need to get a slick convertor and gearing to make it work. Or you can add a couple points or more of compression and get that snap back. The cost of pistons and balancing is less than a gear and convertor swap, and certainly less than the gas bills the low compression required gearing will deliver.
 
moper said:
You can get power from anything to a point. Compression more affects the rpm point of peaks and the overall peakiness of the torque curve, not the peak figures. In terms of your pulling truck you know the rpm you need to maintain wheel speed. Build the engine and gear and convertor the truck to put you where you need to be. For a street car those low compression packages don't make peak torque until 3300 or higher. How often are you cruising around there? You'll need to get a slick convertor and gearing to make it work. Or you can add a couple points or more of compression and get that snap back. The cost of pistons and balancing is less than a gear and convertor swap, and certainly less than the gas bills the low compression required gearing will deliver.
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To an extent...

My engine peaks at 3900-4100. Yes, the same torque for 300rpm. The curve is very broad and pretty flat. It's a 440 with 10.5:1.

BUT, you want to talk about usable RPM? My engine starts making over 300hp and over 400ftlbs at 2500RPm. I wasn't going to start a pull lower than that but imagine what it makes even off idle?

I'm a fan of compression so long as it runs on pump swill.
 
And another thing worth mentioning, AGAIN, is dyno numbers are just that.......numbers. Lots of "big hp" builds, when installed into real life cars, don't back up the dyno numbers. Big dyno numbers sell engine builds, think about it
 
replicaracer43 said:
And another thing worth mentioning, AGAIN, is dyno numbers are just that.......numbers. Lots of "big hp" builds, when installed into real life cars, don't back up the dyno numbers. Big dyno numbers sell engine builds, think about it
Click to expand...

It's all about the package as a whole.
 
Thanks guys. I'm on my way to a smog build. I have 4.10s already will be finding a 727 and a custom 4000 stall convertor
 
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