76Cutlass_442

Hello, as most of you know i have a 76 442. i finally brought it to Great Lakes Dragaway and ran it down a couple times. It ran constant 16.5s at around 84-86mph with a 60ft of 2.51. Now i think it was very doggy off the line and wasn't very happy. Would my timing be off if its that doggy off the line? then my last two passes were 18 sec passes because all i did was smoke tire off the line. im running Mickey Thompson Sportman S/t 275/60/15s in the rear at 40psi. Even though the engine is being pulled soon, i thought it was going to run better than it did with the few parts i have bolted on. Thanks

76Cutlass_442

svnt442

A 76 350, even in a 442, wasn't all that powerful and being in a car that weighs right at 4,000 lbs doesn't help. Add to that the likelihood of either a 2.56 or 2.73 rear end and you're not getting down the track that quickly no matter how hard you try. The lack of a posi doesn't help your cause either.

And 40 psi seems a bit much for air pressure in those tires. I'd try 25-28 and see what happens.

oldsmobiledave

Welcome to low performance. That is typical of how they ran when new. However you can improve your 60' time by switching to a 26" tall rear tire for the track & lowering the tire pressure. 40 psi is outrageously high for traction. Your tall 275 60 15s out back are nice & wide but the 28" diameter combined with your rear axle ratio which is likely a 2 series gear is killing the bottom end power.

BangScreech4-4-2

16.5 @ 85 is surprisingly good for that car!

oldcutlass

Doesn't sound too terribly bad for your model year. Tell us about how its setup, timing, gears, etc. You may be able to squeeze a bit more out of her.

GEARMAN69

If it smokes the tires that's a good sign it will improve a lot. If it's an open rear add a posi and gear bump like a 3.08,3.23 or 3.42 easy to find 8.5 stuff.Hoping it at least has true dual exhaust with no catalytic converter and an.open air cleaner

coppercutlass

I agree that its not a horrible e/t. with little tweaks i can see high 15's.

Rallye469

Worried about keeping it original?
Swap out the 350 for a 455 out of any 68-72 land yacht and pull low 13's all day long...if not better.

Good luck!

-Pete

wr1970

That really isn't a bad ET for the car and weight.I agree with rallye the easy way out is a 455 swap out of a land yacht.I also think there is more in your combo with a little more tuning and a gear change would help. Anyway cool ride have fun with it and post some more video when you go out again.

GEARMAN69

Copying over OP opening text from another thread.
"Hello, i have a 1976 Oldsmobile Cutlass 442 with numbers matching 350 with 95k Original Miles. The 350 has an Edelbrock Performer Intake Manifold, Hedman Long Tube Headers to X Pipe with Flowmaster 50s with a Quick Fuel 600cfm Slayer to top off the Cake.. (not including K&N Airfilter, Accel Wires and Brad Penn Oil) "

So the 16.5 was not spinning I assume if the 18's were. But 2.5 60' is real slow. Was this thing fully warmed up like straight off the highway. Basically did you leave it running in the staging lanes before run or did it stay turned off to cool down as much as possible? Assuming you have not re-curved distributor yet with lighter springs that helps a lot on low end improvements besides temperature. If you have a 195 T stat try a 180 or 160 depending on seasons you drive in.

HWYSTR455

You're pulling the engine soon? What's the plan there?

If you do anything, you should be making changes to the chassis to compliment the new build. Depending on what's going back in, it could or could not benefit your current engine/power levels.

Small blocks need gear and stall, no two ways about it. If a small block is going back in, you can do gears now, and not have to change anything when the new engine goes in. In my opinion, a SBO needs no less than a 342, 373-411 is best. Stall needs to be in the 2800-3600 range, depending on the cam selected. BBO a 308-373 is good, depending on your intended use of the car.

Gears and stall will impact how you tune, so if you are planning on a gear/stall change with the new config, timing curve and carb adjustments would only be temporary improvements. But, those two areas could net you some considerable improvements. (If done correctly)

Start by determining your advance curve. Post what it is now, along with your gear. If you're not sure how to figure out what your current advance curve is, do some homework. It's not that difficult to figure out. A dial-back timing light and a hand vacuum pump is all you need.

Whatever you do don't blindly throw some 'performance' weight and spring kit in there, most of the time they just make things worse. Weights and center plates, it's best to use OE ones. Period. Or an aftermarket distributor.

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BangScreech4-4-2

Just curious -- why do you need a hand vacuum pump to do the timing?

GEARMAN69

Just the springs from the re-curve kit Yes with stock weights. I prefer using one of the lightest and one of the medium tension ones from the kit and try setting total timing to 35 with vacuum advance disconnected. Besides 160 T stat a set of 3.42's in place of the 2.56 ? gears, the other huge improvements would be in a rebuild or maybe re-ring with a heads swap as mentioned to some #5,#6,#7,#7a heads with bigger valves, a nice little cam and converter swap.

HWYSTR455

To check/verify vacuum advance.

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BangScreech4-4-2

Huh. I usually just disconnect it and plug the hose. Maybe that's my problem.

HWYSTR455

That's the way to check initial, and mechanical. To check your vacuum can, hook the hand pump up to the vacuum can with the light on and see when advance starts, and when full occurs. It's a range of vacuum, and you should know what total advance the can gives you too.

You should know what your vacuum is at idle, and as you crack the throttle, as well as up to like 2500 rpm. Most Olds I've seen need the total amount of advance from the vacuum can limited. Usually 6 - 10 degrees is right for a higher CR build.

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HWYSTR455

To plot your mechanical, make a chart with 500 rpm increments from 500 to like 4500. With the timing light on it, record what your timing is at each RPM increase, in those 500 RPM increments.

So on the left, the scale is 0 - 50, and along the bottom, the RPM scale.

Here's an example of me working out the timing curve on a Pontiac 400. The principal is the same for any make though.

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HWYSTR455

Another example of me working out a 455 timing curve. Might be a little easier to read this one...

.

80 Rocket

This engine will be in my shop soon. I'm going to teach the young man how to make some power with a little 350.

We have talked converter/gears as well. Maybe we will track dollars spent for all to see what can be done on a strict budget with a little know-how.

wr1970

Hell ya now that will be a happy out come no doubt!

BangScreech4-4-2

Absolutely. You may have helped me to solve the part-throttle detonation problem I've been having. I got an adjustable VA can but even with it backed all the way off, I still get spark knock. I'll have to get the vacuum pump and measure the advance properly. Thanks.

oldcutlass

Most vacuum can adjustments are for the amount of vacuum needed to advance, not the amount of total advance. You need to buy or fabricate a limit stop. You need something like this:

HWYSTR455

Yup, that what it sounds like to me.

Keep in mind that the can only has 9 turns from the bottomed out clockwise setting, and if you go counterclockwise past 9 turns, the set screw falls out, and there is no longer any adjustment.

I've tried to get the screw started before but have only once been lucky doing that. Most of the time you have to replace the unit.

the advance stop oldcutlass posted is what I use, but depending on the body of the distributor, sometimes you don't get full range, and have to mod the cam.

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BangScreech4-4-2

Good to know. Thanks again!