Overheating help
 

Good day all, I am stumped. 50 miles on a new Kauffman complete 461 build. Edelbrock Pro Flo 4180 stat, derale twin 2000 CFM fans, brand new cold case rad and mezeire 55gpm electric pump. Fan 1 comes on at 185, second at 190, I can't keep this engine cool. Even while driving, the fans are on, and temps climb. I verified the flow of coolant in the rad when the stat opens flows from the upper rad hose side to the passenger side of the rad. Initial timing is 15 degrees, ( unlocked at 12 degrees during the setup in the pf4 app) 10 degrees vacuum, 36 deg all in at 3000rpm. Short term fuel is at 1-2 , long-term in the app is 19- 29. , But people on the edelbrock forum say don't focus on the lft. The car starts right up, idles well, I just don't know.
The one thing I do notice, when I am setting up the timing with a msd timing light, the timing bounces on the balancer. I used tinfoil on the pickup, and it reduced the amount of 6al spark shower when using the light. When I look at the base timing in the app, the timing bounces 3 -5 degrees consistently. I had Jeff KAUFFMAN put a new poly gear on the pf4 dizzy to go with my hydraulic roller.
I have no idea why I'm running hot.

Were the top rings clearanced for the KB pistons?
Do you use a real fan shroud.
Do your fans pull from the Whole radiator? Or gaps on corners and middle?
Did you check temp at T stat with an IR Gun?
I would start with the IR Gun, then 160 t stat, then seal up any of the radiator to maximize suction, But if the " shroud" is flat and up close to radiator.. your cooked... like water, air hates corners, especially sharp ones.
Good luck..

The Derale fans have their own shroud, it covers the entire surface. They are puller fans. I have a Autometer sender in the same water crossover, the PF4 sender is on the right side of the T stat, the Autometer is on the left.

Verify those guages with an IR gun.
How much shroud do you have in thickness? These electric set ups were NOT designed by an engineer, and may work for a stock 8:1 engine.. but actually don't cool corners, edges, etc very much.
Doing the 421 mod would help a lot too.

421 mod?

Drilling an extra hole not included in the deck of the block to allow steam pockets to escape. It was included on some 421s, hence the name.

Here's one link to making the modification:

https://forums.maxperformanceinc.com...t=421+deck+mod

There are many threads available with using "421 mod" in the search function.

Thanks, I actually did that myself 40 years ago, on an old 400, it just seemed odd that the head gasket didn't line up .

Thanks, I actually did that myself 40 years ago, on an old 400, it just seemed odd that the head gasket didn't line up .

UPDATE, hard to believe, I installed a 160 stat, now it cruises at 183, 190 at a stop light, the fans cycle on and off, and temp drops back to 183 or so at cruise.