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Reply to "Oops I'm doing it again....I lost my head..."

DYNO RUN RESULTS!

Now we're not talking any top fuel results out of a small block here. My goals were simple....make "good" reliable street horsepower and torque, and have and engine that may last 60K or more miles...of romping through the hills and dales of the neighborhood!

Limit was about 6000 rpm's for the purposes of this build and my comfort level of spinning jack-shaft components! You can see where the cam and intake run out at about where they should. NO optimization of max spark advance was done here on this thrash....this was only to get mixture set properly.

Here is why I had to change to the standard volume oil pump. About 5500 rpm's the valves started to float.... Note the mixture at the bottom of the chart shows a RICH mixture...not even on the charts yet! This was last year when I got the car running again, August I believe. Maybe late July.
 

Fast forward, to new STD VOL  oil pump, and last weekend! Note no more breakup at 5500. Mixture magically has not changed yet... LH side
 

After leaning out the secondary jets from a 68 down to a 65, and reducing the primaries from a 64 to a 59, we obtained the best results! Best torque and HP of 320+ ft-lbs/ 309HP. Nice broad torque curve peaking at about 4500rpms. First we did secondaries and noticed a big change. Then the secondaries and obtained the final numbers as follows.

RH side of engine
 

What we finally ended up with, for some reason, was the LH side of the engine being a tad more rich than the RH side. To cure this, we had to "cross jet" the carb, or make the jets different on each corner of the carb.

What I did, was increase the RH primary jet size from a 59 to a 64 (all we had for jets!) and go from a 65 to a 66 on the RH secondary.

This served to make the RH results more rich, closer to the LH results. We did not go back and recheck the LH side.....

We lost a couple of HP, but that could have been anything...me on the pedal....but the results are 1) much better fuel utilization, should be better on gas! 2) confirmation of a good solid street motor for the GOose!

 

If you figure that the ZF can rob up to 25% of horsepower from an engine due to rotational mass etc, that would put this little 302 stroker (331CI!) at somewhere near the 400HP mark at the crank! Driving results back this up....as it is an absolute kick in the shorts to roll on the throttle and feel the secondary circuits kick in....and push you back in the seat!

It has been a tough project with no shortage of obstacles and challenges! In the end, definitely worthwhile!

Now, to get that ZF linkage adjusted properly! When I lifted the front of the engine a hair to make the oil pan and air cleaner fit optimally, it changed the relationship of the trans linkage....again! It's always something....

EDIT 040620: Again, ZF shifter issue was my mis-adjustment of the shifter rod support trunion such that the shaft touched the firewall shifter shaft tube in 2 & 4! Once I put the trunion back where it was....all was good!

Ciao!
Steve

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Last edited by mangusta
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