Tony72Cutlass'S'

Eric,

i've read those articles that you posted, they've compelled me to pick up the crane cams kit and try to recurve my HEI in my 72 stock 350, thanks for all the info guys

-Tony

D Appeldorn

Trip deuces,

what kind of spring setup do you have?

They put the 2 lightest springs in mine.
It runs nice, but is'nt that to much?

Or the lighter the springs the better it would be.

in the manual it say's that the 2 lightest spring wil be all in under 3000 rpm.

Jus't curious

TripDeuces

Yeah they give you the generic setup when you get it. I try to have all my timing in by 3400-3500. I forget what set of springs that is. There is no set way to do it. You have to see what your combination will except. With 10.25 compression, iron heads and 91 octane gas I'm a bit conservative with the 330. It will rattle if you get crazy with it. Look at the charts and see which springs give you the same type curve and go from there. You might find you can get away with earlier timing or not. It's trial and error. Remember it's better to err on the less aggressive side with timing on a street car. Some knock/detonation can not be heard well but could still be doing damage.
I always try to get the most initial I can without it hard starting then work from there. I can't tell you what will work on your vehicle you have to experiment and see. As an example my previous drag car had all the timing in by 3000 and had a total of 36. Some can get away with all in by 2500. It's trial and error my friend.

George

D Appeldorn

I do not hear any rattle
Becouse of my exhaust it is difficult to hear.

I gonna check this week how fast the timing set's in.
They removed the stiffest factory springs and put the lightest in it.
Maybe becouse i have a low comp it need the lightest.

Do i have re gap my plugs again? or leave it as on hei prefered gap.
And how do i reconect my tach? on the + on the coil?

Saw in the instructions the grey wire is to adjust a rev limit, so it is not to atach the tach?

D Appeldorn

Tripdeuces,

can it be that the springs act differend on differend engines?

I looked at my timing today,
with the 2 lightest springs and the bleu bushing you get with the msd ready to run i got
14 degrees stationairy and at 3000rpm 30-34degree initial.


and with vacuum at 3000rpm i got 45 degrees and above that rpm it goes till 55degrees.

So it is all in with 45-55 degrees of timing.

Strange that it is not matching the advance curves that are in the instructions paper.

TripDeuces

I think what you're trying to say is you have 14 INITIAL (at idle) and 30-34 TOTAL at 3000rpm. So the blue bushing is giving you 20 degrees in the distributor (I'm discounting that 30 degrees number) According to MSD that blue bushing supplies 21 degrees of distributor advance so your initial timing is closer to 13 degrees from your example. Also according to those instructions if you use the two lightest springs (silver) the advance is all in by roughly 2400 rpm. A blue and a silver will give you that 3000 rpm point.

Can it be that the springs act different on different engines?

Sure they can due to manufacturing tolerances, friction, etc. It's not going to be a big difference but it can happen. Just make sure the weights move freely and nothing is binding. The advance curves in those instructions are for mechanical/centrifugal advance only not vacuum advance.
I think the vacuum advance part of this whole thing is confusing you, just stop worrying about it. Vacuum advance is for economy. In other words when you are cruising along at light throttle/part throttle conditions. Under light loads like cruising it helps fuel economy. All that vacuum advance comes out of the equation when you floor the gas pedal. Vacuum in the engine goes to zero or close to it at WOT and the vacuum advance ceases working. This is why race cars don't have vacuum advance, it's not needed when the pedal is always to the floor. In fact they allow you to stop the vacuum advance from working with a lock out mechanism if you want.

If you don't have a degree tape on your harmonic balancer I would suggest getting one. It makes all this easier to read and understand. A dial back to zero timing light is handy also.

D Appeldorn

I do have the degrees on my balancer, that is how i read the timing.
I do not have a dialback to zero timing light.

I have 30-34 total at 3000rpm with the 2 lightest silver springs, vacuum disconected.
With vacuum connected 45. and just under 4000rpm it is 55degrees.

That is my point, i get 34 at 3000rpm with the 2 smallest silver springs.
I did let it curve by a garage for usa cars and parts, and noticed that i have the 2 thicker zilver, and the bleu springs in the box.

So stay with the ligtest springs? with my "corect" readings from the balancer.
Or go with the silver and bleu.

Engine runs nice.
Without noticeing any nock

TripDeuces

If you're happy with it I'd leave it alone. It's not uncommon to have 45-55 degrees with the vacuum advance hooked up. Switching to heavier springs just makes the advance come in later and you said it runs fine with what you have so stay with it. Since there is no knock or pinging you've accomplished your goal. I'm glad things worked out for you and your beautiful car.

George

PS. I'm putting the new exhaust on mine. I can't wait to get it done and back on the road. The weather here is really starting to get nice now.

D Appeldorn

Nice,

i did put a new exhaust on mine last winter.
did make it myselfe.
I found out that it was not that easy, and left the H pipe off.

I think the exhaust must also be easy to remove and not be that heavy.
So i am thinking of puting a flange in the H if i gonna mount a H pipe.

RonzBoyz4

D Appeldorn
- Did you get your olds set up?

D Appeldorn

Yes, for a low comp engine it is realy strong.

used the lightest springs in the kit.

did try a heavier sping setup but it gives me less power.

i have a low comp engine build for torque, performer intake and carb, double exhaust without H or X pipe and can easely spin the tyres.
it is vast enough an can compete with most cars with my full size.

if i gonna make it faster or stronger i think i need a stronger torque conferter.
i use my th400 build for the 350 engine.

initial is set to 14,

i think i had to use the lightest springs becouse its a lowcomp engine ( that is what i'm told)

Don't care about the hp, the torque is interesting do.
it's easy to spin the car around, burn the tires or make a fast sprint competing a other car.

only my carb is not set right, to rich but just within the mot regulations

my second wish is to get a engine with those specs in my 65 chevy c10 pickup.

Octania

I thought that previously, but in going over all this for the recent 403 From Hell motor, I was carefully noting the vac. vs. advance vs. screw setting on the adjustable unit I bought... and found that the screw on my VA unit ONLY adjusted the travel = the amount of vacuum advance... the initial motion vacuum level and vacuum level required to attain full advance were more or less the same for all settings of that adjusting screw which is reached thru the vacuum nipple.

I understand that another way to accomplish the same thing is to modify the slot in which the actuating rod resides, or place a washer or stepped eccentric "washer" over the tip screw such that the rod's farthest extend point is altered, and thus the total travel is reduced. Another fine way to accomplish the same thing.

I ended up finding the GM PN 1973511 VA unit recommended by many on the web, which only comes in after 10 in. Hg vacuum. Have not tried it yet, but I have it. From my records:

Starts at 12" Hg; Maxed at 17" Hg; Travel 0.199" = 15.5 Crank Degrees

This can prevent the VA unit from introducing too much advance until and unless your engine is fairly unloaded and able to produce over 12" Hg of vacuum. It is however in no way adjustable.