403 OLDS SET-UP

[Chris Borson]

Hi everyone! Great board. Cliff I read your book twice and thank you for all of the information you have included. So I am trying to build a 1709253 for a 403 with 9.5:1, Performer RPM, and a cam with 224/231 duration respectively. I followed recipe one and left the stock 73 jets with 55P rods. Secondary side has CV rods with a K hanger. I followed all your other suggestions in the performance chapter. Do you feel I will be close with this set up or do you have other suggestions?

Also I have used this same carb # on my other car with a 403 and all I modified was discharge ports to .090 and 1/8" bypass holes in throttle plates and it idles great. It is similair in specs but uses a 204/214 cam and 8.5 compression.

Thanks! Chris

[Cliff Ruggles]

Chris, are you using our HP kits for the build?  They contain Viton parts, and high performance parts, plus many other parts required for a complete/correct rebuild.

I would replace the 55P rods with a set of our custom .044" rods.  They will give more control from the APT and a cleaner fuel curve than the "P" series rods....Cliff

[Chris Borson]

Hey Cliff, I used a Hygrade Bluestreak kit for the rebuild. I will place an order for the 44 rods you suggest. That seems like a big difference from stock and makes me think it would be excessively fat! Why such a huge change? Also how about the secondary side and the use of recipe one? Thanks!

[Cliff Ruggles]

The Hygrade kit will NOT contain a high flow Viton needle/seat assembly.  It will not have a float, secondary cam/spring, power piston springs, and many other parts needed for a complete/correct rebuild.

The 44 rods will be fine.  That carb has APT, and even the factory "P" rods were raised up onto the smaller section of the metering rods....Cliff