Harry Mann 68 L78 / L88 Camaro

[dykstra]

Originally Posted by napa68

Progress....... Happy with the preliminary pulls after getting everything broke in. Now run the valves, have a look around, check torque, and switch to Eric's carb.

Tomorrow, some tuning and power pulls

BOING!!!!!

[Chuck_Burg]

Good luck sleeping tonight...

[Crush]

Going to need some bigger stickier tires!!

[Too Many Projects]

Originally Posted by Crush

Going to need some bigger stickier tires!!

He should be looking for drag radials, not bias ply's...

[TimG]

Avons do the trick, when I put them on my Cobra and took of the other tires, it pulled like crazy.

[napa68]

Once everything is back in place, the Polyglass's will help keep the guts of my original rear end where they belong. I believe it was Doug Perry's suggestion to another member, about upgrading the axles at a minimum before the sticky's. Perhaps after that, a set of M&H's would be in order. Again, just like it's the early 70's

Much of the build is old school. Certainly with different cylinder heads and camshaft, I could probably tack another 100hp onto the combination. In the name of authenticity, old school is in order.........just like the owner

[napa68]

Once the engine was broke in, the preliminary pulls yielded 530hp @ 5500 RPM (and climbing) with the shop Braswell Holley and 36 degrees of timing. On Wednesday, we bolted on Eric's carb with a plan to spin it to 7000 RPM. We did struggle with the ignition a bit (point bounce in the Roto-Faze distributor) and that limited our pulls to 6000 RPM.

Regardless........with 40 degrees of timing, the engine yielded a peak of 575hp @ 6000. The average HP from 4100 to 6000 is just under 500. Better yet, the average torque from 4100 to 6000 is almost 520 lb.ft. I think it's fair to assume once the ignition is up to par, the better part of 600hp is realistic.

Considering how outdated the camshaft and cylinder heads are, I am quite pleased with the outcome. Certainly, more modern heads and camshaft would produce some notable improvements. In the spirit of the car and the build, I am glad I went this route.

While this is not a "stock" L88, it is pretty close. There are a few concessions in the build that deviate from a spec L88.
-the 842 heads did have 2.30 intake valves installed by a previous owner. There was some blending in the bowls to accommodate that change. Otherwise, they are relatively unported.
-Roller rocker arms
-ZL1 camshaft that was reused
-Eric Jackson's Holley 850 that he built specifically for this.

Really, just an old school 12.5:1 427

I'll take he opportunity to give a shout out to Eric Jackson. He was tremendously helpful on not only the build of the carb, but also the overall package. Steve from AMS was impressed with how spot on the carb is and how the fuel curve looks under power. While not pictured, the EGT's were spot on.

I also have to give props to Steve and Chris from AMS. I have dealt with Steve for about 20 years now. The work is fantastic, he is fair in his charges, and always make these projects a joy.

[napa68]

[69M22Z]

Very nice.

[dykstra]

So bad azz!! That is music to my ears! Bravo Tim!