Project X-Ram

[uscrichter]

I was going through some old GM NOS parts I had for years in storage that I though to use on the 302 X-Ram engine I will be building this summer and was wondering if these parts would work and if anyone has used these  type of light weight flywheel and if so did it improve performance? I also found a #140 off road cam that I plan on using and need to find out if that valve spring is correct for it? Thanks in advance.

[uscrichter]

The other two pictures didn't go through, here they are!

[uscrichter]

Flywheel

[BillOhio]

My Z has the 140 cam and springs in it.  They had orange paint on them. If you have the aluminum retainers that were used with the springs, dont use them.  They were prone to cracking and bad things happen.  I was lucky mine survived

[uscrichter]

Great advice on the springs, thanks! has anyone used that flywheel before?

[firstgenaddict]

What weight is the flywheel?
The light ones 15-20# are great for racing a 302 however on the street you have to rev them to the moon to get them going. 

[69Z28-RS]

My Z has the 140 cam and springs in it.  They had orange paint on them. If you have the aluminum retainers that were used with the springs, dont use them.  They were prone to cracking and bad things happen.  I was lucky mine survived

If I'm not mistaken, There was an over the counter lightweight titanium retainer that could be used with the HD spring...  I probably have the PN's on a receipt somewhere...

[uscrichter]

I will check the weight this weekend, seems like it would allow for a much more responsive rev and with the off-road cam and all that carburation would be welcomed to get the HP up to the sweet spot quicker? I know the configuration is not friendly as a daily driver,  I plan on using it for shows and weekend fun.

[69Z28-RS]

I ran with the lightweight flywheel on my 302 when I rebuilt it back in '76...  It revs quickly, but a little starting 'torque' is lost without the heavy flywheel.

[uscrichter]

The flywheel is 14.6 pounds to be exact.

[uscrichter]

Any recommendations for the rear gear ratio with this set up?

[firstgenaddict]

M20 or M21?

[uscrichter]

M21

[PHAT69AMX]

? For Street and Strip, how about 3.73 Gears like a stock Z28 ?

3,600 lbs total car & driver,
355 HP NET to the ground,
using published "physics formulas" yields:

12.00 Sec 1/4 mile "Ideal Target" and
109.0 MPH 1/4 mile "Ideal Target" and

for 109 MPH:
26 inch Rear Tire Diameter by "spec"
=
25 inch Rear Tire Diameter "Effective" ( 1/2" squisch )
=
1,465 RPM Rear Tire at 109 MPH
times
3.73 Rear End Gears
=
5,465 RPM Motor at 109 MPH

-----

Some 25.5" to 26.5" dia range Tires:

25.5" - 195/75 R14, D78-14, E60-15
25.6" - 245/60 R14, 225/60 R15
25.7" - 195/70 R15
25.8" - 275/50 R15, E70-14, G60-14, C78-15
25.9" - 215/70 R14, 185/75 R15, F60-15
26.0" - 255/60 R14, 215/65 R15, E78-14
26.1" - 205/75 R14, 235/60 R15
26.2" - F70-14, D78-15
26.3" - 205/70 R15
26.4" - 225/70 R14, H60-14, E70-15, G60-15
26.5" - 195/75 R15, F78-14

[uscrichter]

Very impressive! You must be an engineer, I appreciate the help and will plan on leaving the 4:10 that's with it, I'm planning on driving to shows and occasional quarter mile fun on the back roads so your calculations look like the 4:10 will be tall enough for sure! Thanks again for the help.