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Topic Review (Newest First)
05-31-2010 05:50 PM
sickolds yes i do the trans shifts at 2000 give or take
05-31-2010 05:45 PM
gofastz the car prb has 2.14 or 2.73 gears!! you will def need some 3.73's,, iv got a 87' cutlass with mild 350, flat top motor with "461" double humpers with 10.1CR, a 288 degree cam with 204/214 420"/442" a victor jr and a 600 carb, a 2100-2500 stall and some 4.10 posi and it smokes the tires like nothn!!!
05-31-2010 05:24 PM
SUX 2BU Do you have a tach in the car? What RPM and speed can you shift from 1-2 at? A stock 1982 rear end will most likely have a ratio somewhere in the 2.xx range. My dad's 1981 Regal with a 267 2bbl V8 had a 2.29 ratio rear end! Your 383 will feel like a total slug with a rear gear like that. The stock motor in your Cutty had a diesel-like power curve and the more mild the motor, the more they agree with super tall rear ends. As was said, put a 3.73 gear in there and it will be much much better. I put a hotter cam and heads in my truck and it felt 'okay' after but until I changed out the 2.76 stock ratio to a 3.40 did it get quite a bit better.
05-31-2010 05:16 PM
sickolds well the thing is that i have only done 2 builds 1 was mild 350 (it made the same power as these 383 better burn outs to ) there are lots of things i have to learn
05-31-2010 02:51 PM
cobalt327 It always helps when there is a full disclosure of ALL the info pertaining to an engine is revealed up front, in the first post or two, instead of having to ask for each and every detail one bit at a time. So, if there are any other details that you'd care to add, now would be a good time.

It would NOW appear that your cam might be a Summit Racing #1104. It has 0.465" of lift- right at the maximum that a stock set of Vortec heads will allow before the retainer hits the valve stem seal.

But the real problem is, if the "lil rebuild" did NOT include valve springs that are correct for the camshaft's lift, the valves could well be floating/lofting because the stock valve springs are too weak.

The stock springs are designed to be used w/the L31 cam:

Stock L31 cam specs:
Intake lift- .414"
Exhaust Lift- .428"
Intake duration @.050"- 191
Exhaust Duration @ .050" - 196
LSA- 111

If your valves are floating, the engine might run strong up until the point of valve float, then power would take a definite nose dive, along w/the possibility of popping through the intake and/or exhaust. Sometimes, there will be no popping, it just depends on how bad the problem is.

Does this resemble the way your engine is running?
05-31-2010 10:11 AM
sickolds now im thinking about a single turbo to make up for the lose of power
05-31-2010 10:09 AM
sickolds no just a lil rebuild on the heads. i was just looking for something like 400hp the engine only has 1000 mile or so at first the comp was at 100 now 500 mile later 150
05-31-2010 08:37 AM
Custom10
Quote:
Originally Posted by cobalt327
And what's the head gasket thickness? But I can tell you, this isn't looking good...
diddo that
05-30-2010 11:44 PM
techinspector1
Quote:
Originally Posted by sickolds
yes sir these are vortec oem heads
Are they bone-stock or did you change out the valve springs?
05-30-2010 11:37 PM
cobalt327 Something like 9.24:1 w/a 0.041 gasket, anyway. Given a 5.7" rod, 9.025" unmilled stock deck height, nothing subtracted for bearing clearance.

The 9.7 CR you were told would have been w/a zero deck and a 0.041 quench.
05-30-2010 11:27 PM
cobalt327
Quote:
Originally Posted by sickolds
1.433 pistons decke higt is stock
And what's the head gasket thickness? But I can tell you, this isn't looking good...
05-30-2010 11:11 PM
sickolds 1.433 pistons decke higt is stock
05-30-2010 11:10 PM
cobalt327 If your rear gears are stock, chances are good they need to be changed to a lower (higher number) set. A torque converter to match the onset of serious torque production by the engine will be needed, something around a 3000 rpm stall range, give or take.
05-30-2010 11:04 PM
cobalt327
Quote:
Originally Posted by sickolds
were did that cop 9*** com from i was told it is 9.7 these is onky my second build
It may well be- what is the quench at? If the block is zero decked, the CR will be about w/9.7:1 0.041" head gaskets. And should be OK w/your present cam.
05-30-2010 10:53 PM
sickolds yes sir these are vortec oem heads
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