Thread: Olds 455 runs hot - dyno 210hp rear wheel

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Guys,

I have several issues with my rebuilt 455 olds engine: 1st) the car runs hot. I have added 165F thermostat, new 4 core radiator, removed the ac unit to allow air flow and the fan is a std 6 blade thermostatic controlled clutch fan which did make it better , however it still runs hot over time. The last thing I can think of is to add a fan shroud. What else can I do? 2nd) I did a dyno - the rear wheel hp 210 with 300 ftlbs. torque - I'm lost......Could my cam be improperly positioned?

Here’s my build:
Block: 1974 Olds 455
Machining: Bored over .060 = 468 cubic in, Block is Square and Align Bored
Pistons: Probe SRS 2618-16 Aluminum Forged Part #14476-060 10:1 ratio
Stroke 4.250, C/H 1.735, Bore 4.185, Weight 564/578g
Heads: 1968 Iron heads - 403686E 80cc 2.000, 1.625″ Milled: .005 /.010”
Cam: Isky Cat #691271 Grind Style -270-MEGA HYDRAULIC
Specs: RPM: 2000-6000, Lift: .496, Dur: 270° Dur: 221°, Lobe:108°
Timing Chain: Cloyes
Intake Manifold: Performer Edelbrock Aluminum 2151
Carburetor: 1402010VE - 750 cfm Speed Demon - Electric choke w/Vacuum
Exhaust Manifold: Thornton Reproduction 1965-1967 w/functioning damper.
Modello: Windage Tray-WT-200 & Valley Tray – VT-581
Waterpump: Alum AP403
Pulleys: Alum
Rear End: chevy 10 bolt 3:42 posi
Trans: 350 Auto 3 speed w/shift kit
Radiator: 4 core
Fan: 6 Blade thermostatically controlled clutch fan.
Air Cleaner: Forced Air Induction

Your thoughts would greatly be appreciated,
Rich

A shroud is very important for proper cooling, makes the air come through the radiator and not just around it.

Change your thermostat to a 192, to give it more time in the radiator..ensure all air is purged out of coolant system...

How is your timing? Running hot and low HP could mean late ignition timing.

wow I'd expect LOTS more hp from this.
have one (Olds 455) laying around to install myself

Make sure it isn't running too lean.

I have a 455 in my W-30 that I built about 10 years ago and I run headers. My first question is why you have a damper on the exhaust manifold as those engines warm up just fine in factory trim without one. How hot is hot, I run a 160 in mine and it stays a nice balmy 165 with a 4 tube brass core, this is a 72 factory 4spd W-30 car. Gets up to 185 or so on a 95deg day. It has always run up around 210 or a little more with the funky 3 tube core it came with and the factory cam.

Next question is did you use the advance/retard chain set from Cloyes and how much did you advance/retard it.

455 .060 over
C casting heads
Mondello JM 28-29 cam (ugly idle)
Rhodes lifters
Offy Port-O-Sonic intake with QuickFuel 850 annular
Milodon Cheater gear drive at 0 degrees

Really low numbers anyway, I would expect 400 @ high 400's or a little more torque.