Feel like my 440 should be faster

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PRH said:
Let’s revisit the CR-

-What part number pistons, and set at what deck clearance?
-heads were measured and the chamber volume is?
-gasket bore and thickness(or part number)?

Other thoughts…….
Unported stock heads are definitely a restriction if trying for better upper rpm power.
A [email protected] cam, With modest CR and especially at your elevation will want more stall speed(32-3500 actual flash stall).
Something like a tight 10” converter.
A better match cam wise for something that only has an actual flash stall speed of 2500+/- is going to be about 15*@.050 less.

A cranking compression test is worth doing.
Engine warm, throttle wide open, all plugs removed.
I usually look for pressure on first pump, 4 pumps, and max pressure(7-8 pumps).

My experience is that from the drivers seat, a properly tuned, appropriately sized DP carb will “feel” hotter than a VS carb………even if/when it’s not any quicker at the track.
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Not sure in part number I would have to look back.

Heads 90cc (not measured, going off standard 452 specs)
Piston Dome volume +7
Bore 4.350
Stroke 3.75
Measured Piston to deck .029”
Using Mr Gasket .020 steel shim head gaskets
 
PRH said:
So, L2355 pistons…….flat top 4 valve reliefs?

Looks like 9.38 is “close”, at worst.
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That sounds like them. I spoke with Howard’s about the CR and they said this cam would be a great fit with my setup.

Just put this motor together, at this point I’m not changing heads, converter, cam, etc… is what it is. I’ll do some different gears this winter and just enjoy it from there.
 
How many miles on the engine now.

Is the carburetor opening all the way with the accelerator pedal? Need 2 people to check this.

Are the secondaries opening fully or at all? Maybe you are driving a 440-2bbl.
 
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I like your build and believe you're closer than you may think. Get your rear end gears tightened up and I think you'll be surprised. I've had combos geared too high then made a gear change to a higher ratio and Bam big smile!
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These stand out to me

9.38.1 compression (calculated)
A little low, but that 103lsa will help with this.

452 heads stock unported with Howard’s springs specs for the cam
bone stock heads!!! Heads are where power is made.

Quick Fuel Slayer 750cfm carb, vac secondaries, 1” spacer
Smallish carb and vacum secondaries are helping you

Schumacher Tri Y headers
Teeny wheezer tri-y headers. I had these and went to 2" full length, night and day.

Pypes 2.5” stainless exhaust with Street Pro mufflers
smallish pipes, christ my 5 cylinder volvo has 2.5" exhaust.

Hughes 2500 stall converter
This is less than stock in some cases.

3.23 gears
pig tall gears. This would be the first thing i'd change. I realize you don't have an overdrive, but most people would be shocked to see what gears their cars need to actually perform properly.
 
The thing about the CR is………at that high of an elevation, the CR is “effectively” less.

After you do a cranking pressure test and have a real number to look at.
Use the Wallace cranking pressure calculator to see how close it is.
Then change the baro pressure to something that represents being closer to sea level.
The cranking pressure number will go up.
Now, start lowering the CR until the cranking pressure number is pretty close to what you’re seeing from the test.
Whatever CR you used to come up with that result is basically what the effective CR is at your altitude.

Edit-
So I ran the numbers on Wallace…..
Current baro reading(station pressure) at Denver airport is 24.79”.
For a 446, 9.38cr, int closing point of 67abdc, and 24.79” shows 121psi gauge pressure.
At 29.50” it would be 144.
For the gauge to read 121 at 29.50” the CR has to drop down to about 8.25:1
 
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IMHO, probably a toss up between changing the gears (not street driven I guess) and having the cam reground for your combo (just less duration for lower ivc for more dynamic comp for the 9.38:1 static comp), then swap to the old converter which should stall higher than the 360 with the 440 but less than 2500 and get some of that around town, low end torque back and lower trans temps.
 
standup303 said:
That sounds like them. I spoke with Howard’s about the CR and they said this cam would be a great fit with my setup.

Just put this motor together, at this point I’m not changing heads, converter, cam, etc… is what it is. I’ll do some different gears this winter and just enjoy it from there.
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Converter change will make more difference than gears.
 
What size converter would yall recommend for my setup? If I ended up going to trick flow heads one day would that same converter still be applicable? (which I believe have a smaller chamber volume and would raise my compression to about 10.2:1)

I will definitely be going to at least 3.73 or even 3.91s out back this winter.
 
How fast was the car with the previous 360 engine? Was it a stock 360 or modified?
Will play a big part in your perception of what is "fast".
 
Stock port/valve 452 heads have me scratching my head when you have a nice size roller cam, roller rockers, etc. This is holding back your motor on power. 3.23’s got to go if you’re looking for snap your neck performance. Put 3.91’s in first and see if you’re happier with the performance, should make a huge difference. If you want to cruise on the highway, then keep the 323’s put in a mild hydraulic cam and lose the high stall converter. Just for reference, I have 411’s in my duster and a 26 inch tall tire and turn about 3200 RPM at 60 miles an hour.
 
'Sick of throwing money at it'.

Probably the least expensive 'fix' is a cam change. You have UNPORTED factory heads. These will limit upper end hp. No point using a 6500 rpm cam with 5500 rpm heads. It just leads to tears.....
I would try & find a 220-225 @ 050 cam, 108 LSA, single pattern.
Might be tough to find in a roller cam.

A back up would be a FT cam such as the Isky 270 Mega. Find some factory lifters, have them re-faced & good to go. You can also use SB lifters, maybe easier to find...
 
Bewy said:
'Sick of throwing money at it'.

Probably the least expensive 'fix' is a cam change. You have UNPORTED factory heads. These will limit upper end hp. No point using a 6500 rpm cam with 5500 rpm heads. It just leads to tears.....
I would try & find a 220-225 @ 050 cam, 108 LSA, single pattern.
Might be tough to find in a roller cam.

A back up would be a FT cam such as the Isky 270 Mega. Find some factory lifters, have them re-faced & good to go. You can also use SB lifters, maybe easier to find...
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How is his cam a 6500 rpm cam?
 
j par said:
Sorry, you were tooting your horn so loud It was making my ears ring...
I'm not the one trying to matter....
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you're pretty soft and tender. I was joking around with fishmen67 like I do often in many threads. Started in post 19.
 
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