Test Results Are In!
 

Some of you may remember that I had a crankshaft failure at Norwalk last year. It was an 11:1 .035 over 455. OE block and crank, Eagle rods, SRP pistons, SD Performance 325 cfm CNC heads, Comp Street Roller cam 266/272 duration on a 110, right at .650 net lift, 4150 Northwind intake with a 2" tapered spacer/adapter and a 1050 Dominator. TH350 with a 10" PTC that flashes to 5000 and 3.73 gears, 275/60R15 ET Street Radials. It was a good running combo and I hated to loose the shortblock but that happens sometimes using a 50+ year old cast crank.

Moving forward I decided to go with an All Pontiac aluminum block, 4.350" Mahle pistons and rings, Molnar 6.8 rods and a Molnar 4.375" crank. It comes out to 520 ci and it has the same 11:1 compression as the 463. I used the same heads, cam, intake and carb. I got it together just in time to take it to Norwalk this year for it's first passes. Interesting that the bore/stroke ratio is the same for both engines. The aluminum block is supposed to be about 60 lbs lighter than an OE block but I added weight back to the car with motor plates, heavy trans bellhousing and remote oil filter system. The car should be within 10-20 lbs of what it was before.

I really didn't know what to expect on the track. I knew it was possible that it wouldn't pick up much if it did at all if the cam/heads were already maxed out on the 463. Anyway, the 2 time slips here show the fastest passes from last year and this year. This is with no carb tuning and conservative timing on the 520. Needless to say, I'm very happy with the results!

The results look fantastic to me. What was the upshift rpm, trap rpm?

Shifting at 6500 and 6400 through the lights. I forgot to mention, car 158K.

Did you spin on the last run?


Looks like good time for the 9.77 pass.


:)

Never had any traction issues all weekend or any time I've been down that track. Prep is always top notch! The 9.77 was my last pass for this years Nationals...first round of eliminations on Sunday.

Oh, OK. Went by the date and times on the app.

That's a good improvement still.

:)

Probably happy with that. (other than the red light :eek:)

:)

What does the car weigh?

Right at 3300 with me in it.

The 10.229 last year at Norwalk is 610 Hp calculated using ET and weight. Your 9.93 was 666 Hp and your new 9.779 is 697 Hp, so you got an additional 31 Hp (approximately) from the increase in 57 cubes neglecting weather differences.

Thanks for the calculations! The temp, humidity and DA are listed at the bottom of the timeslips I posted. They are very similar and it's the same track so about as close to identical conditions as you can get. The 9.93 run was at a different track with great air. 55 deg, 25% hum 500 DA. Anyway, I'm very happy with how the car did on it's first outing. It was deadly consistent which kinda surprised me considering the added torque and HP and no suspension tuning.

Nice improvement!
Just curious what valves (intake and exhaust) are in your heads?

Thanks! Ferrea 6000 series 2.19 in 1.77 ex

I think this is a huge success.

What size headers?

Thanks! I have Maddogs with 2" primaries and 3 1/2" collectors. I run 24" collector extensions on them when I run it open. 3 1/2" Pypes Race Pros when I want mufflers. Open was about .08 faster with the 463.

Those valves worked with the srp pistons in the 455? Was the stock block a 455 or a stroked 400?

455 block. Yes, the valves worked with the SRP pistons but only after I modified the intake valve pocket. The radial clearance was too tight.

Thank you, sorry to sidetrack the thread.

That thing was flying this weekend. I’m glad everything went so well for its first time out. I bet there is more there with a little tuning

Thanks Chief! I was definitely surprised how well the car did with so many changes. It's almost like the car knew how important it was for things to go well! I'm sure there is a little more in it with some tuning. Congrats on your wins Sunday!

You keep going faster and faster.
Damb good job buddy.

GT