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Discussion Starter #1
There aren't any dynos around this area so I am limited to doing 0-60 tests and recording the results to determine if my mods do any good.

I guess that is a good real world approach to it all anyway....

When I first bought my '79 L82 (225 Hp stock out of the box) the 0-60 time was 7.8 seconds over several trials. (I think I saw somewhere that the published time was 6.9 for a new engine so I guess loosing a second over 28 years was OK and expected.)

I've been looking for a way to get the Hp's up more. I figured headers would only gain me about -.2 seconds. Boy was I wrong!:thud:

Recently I installed a set of Hooker side pipes and headers with STS baffles......

To my HOLY FRICKEN CRAP :thud: :thud: :thud: suprise I cut a whopping 0.8 seconds off the 0-60 time....and man was the pull from 40 mph to 60 mph (right at that 3800 to 4800 rpm range) un-b-fricking-leavable!

So there you go....real world results.

Maybe you BB guys look at that and think 7 seconds?:WTF Big deal...but to us small block stuck in the crap years of '75 to '82 that kicks serious ass-o-la!

What a great project!
 

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Yeh, getting rid of those old worn out cats will do that every time, it was amazing the cars ran at all, and seeing Wisconsin all that cold start winter running would definately clog the thing quicker than down here in Florida also...much better if you added headers also...

now to do some good tuning to that carb, and ignition look up papers by Lars on doing just that,

:thumbsup: :cheers:
 

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Just for kicks you should see what your time is w/out the baffles. Prolly no better becasue it will be lean but I bet it would sound good! :laughing:
 

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Next big mod should be a trans swap.

Going to a 700 or 200R4 would cut that down nearly another second because of a much improved 1st gear ratio and opporutnity to have a performance stall installed.

Oh...and with overdrive, your MPG will go up nearly 25% or more under optimal conditions due to dropping engine RPM by 40% at cruising speed.
 

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Next big mod should be a trans swap.

Going to a 700 or 200R4 would cut that down nearly another second because of a much improved 1st gear ratio and opporutnity to have a performance stall installed.

Oh...and with overdrive, your MPG will go up nearly 25% or more under optimal conditions due to dropping engine RPM by 40% at cruising speed.
Yup, what Chris, said, ditto.....highly recommended....
 

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Discussion Starter #8
Just for kicks you should see what your time is w/out the baffles. Prolly no better becasue it will be lean but I bet it would sound good! :laughing:
I tried that. It sounded like a NASCAR....but with no baffles in there was no back pressure and the engine surged a lot when you mashed the pedal....but that was only when you hit it hard....cruising was OK.
 

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Discussion Starter #9
Next big mod should be a trans swap.

Going to a 700 or 200R4 would cut that down nearly another second because of a much improved 1st gear ratio and opporutnity to have a performance stall installed.

Oh...and with overdrive, your MPG will go up nearly 25% or more under optimal conditions due to dropping engine RPM by 40% at cruising speed.

That sounds interesting....I would think the swap would cost about $1700 in and out?
 

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That sounds interesting....I would think the swap would cost about $1700 in and out?
OH NO, not unless you go to a pro site somewhere and have it built....

the whole thing should not cost over 500 bux, complete, then sell the old tranny.....so it only cost me ~250 bux to upgrade from a 700 to the 200 4r, that I didn't know existed when I did the 700 install....

but you gotta get to doing it yourself....6', me, Chris, Tim, and others can hold your hand if needed....but you gotta read the book first....

:cheers:
 

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I see them on craigslist all the time for 300-500. Go there and place a wanted ad:thumbsup:

EDIT-
Up the stall speed while your at it a few 100 rpms. Its great on the OD autos because you can lock it in on the highway and never know the difference!
 

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Discussion Starter #12
OH NO, not unless you go to a pro site somewhere and have it built....

the whole thing should not cost over 500 bux, complete, then sell the old tranny.....so it only cost me ~250 bux to upgrade from a 700 to the 200 4r, that I didn't know existed when I did the 700 install....

but you gotta get to doing it yourself....6', me, Chris, Tim, and others can hold your hand if needed....but you gotta read the book first....

:cheers:
hmmmmmmm..............now I've got something to think over while I'm in Canada fishing next week.:thumbsup:
 

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Discussion Starter #13
I see them on craigslist all the time for 300-500. Go there and place as wanted ad:thumbsup:

EDIT-Up the stall speed while your at it a few 100 rpms. Its great on the OD autos because you can lock it in on the highway and never know the difference!
Pardon my tranny dumbness but what's "edit up the stall speed" mean?
 

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Haha. I edited my original post so I put EDIT- beside my added info. :laughing:

You should just increae the stall speed to 1500rpm or so. Its not much difference but it will make the car jump off the line better.

I fixed the post. That better? :cheers:
 

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Haha. I edited my original post so I put EDIT- beside my added info. :laughing:

You should just increae the stall speed to 1500rpm or so. Its not much difference but it will make the car jump off the line better.

I fixed the post. That better? :cheers:
but what is this stall speed your talking about? This that something to do with a manual trany...I've got an auto. How do you up it?
 

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OHHHHH:spanked:

Stall speed is built into the torque converter. It is the speed that it will no longer slip then forces the tires to move. The higher the stall speed, the higher the engine can rev before the trans starts excepting the power. Theres a good read on howstuffworks about it. So, higher stall, engine is more into the powerband, car takes off like a bandit :nuts:
 

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but what is this stall speed your talking about? This that something to do with a manual trany...I've got an auto. How do you up it?
OK, as you know the engine can run with the car in gear, and foot on brake standing still, there is slippage in the torque converter, it works like this....

imagine two fans facing each other...one is turned on, blows air to the other, which blades start spinning...windmill effect...so put them in a round box that sorta resembles a doughnut....
that is a torque converter, simply said...

it takes the place of the clutch....but at speed, you want it to lock up like a stick shift...so....inside that TC, is a clutch like a stick shift, that when enabled, locks it tight so there is no slippage....

now the amount of slippage can be controlled by the internal build of the converter....simply said....so you may well want a 'loose' converter, better take off etc...allows engine to rev higher for any given gear....

ME, I like a super tight converter....so the tranny chrips tires when pulled into gear, and has a change to chrip tires upon upshifting....I like that nudge in the ass when it shifts....not some ultimate SMOOOOTH slusch o'matic the general public seems to love so much....

Stall speed isa relative term, you got more torque, you can get a given converter to 'stall' higher....so it's not a bee all and end all term...

:D yeh, the whole thing is complicated like a MOFO...but U can do it, IF you read first....so get the manuals ....then make up your own mind...
 
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