cam selection for 455 build

[bobolds]

Rebuilding 455 and looking for cam advice.

455 0.030" over
cast stock high compression pistons (sealed power 369P 30)
9.43 to 9.70 actual compression (depending on head gasket, 0.043 or 0.028)
C casting heads, 2.0" valves, mild porting
quadrajet, with dual plane intake
1.5 inch headers

Gearing:

2 speed jetaway
1st gear 1.765
2nd gear 1.0

switch pitch convertor
low angle 1.8 torque multiplicaton 1800 stall
high angle 2.45 torque multiplication 2300 stall

tires: 23" diameter

rear: open 2.78:1

The man at the comp cams phone helpline suggests:
1. XE262H .475"/.480" 218/224 at 0.05
2. OL 268H-10 0.456/0.456 218/218 at 0.05

A cheap option is a local deal. I can buy a used/new in box locally for $50 including lifters/pushrods
OL 265DEH-10 0.472/0.486 211/223 at 0.05 (comp cams)

I am looking for the quickest quarter mile time with my high gearing...and I want the car to be drivable on the street.

[Kennybill]

Hello, First, I would stay away from a used cam and lifters from someone else. I have the Comps 268H cam that is .456/.456 lift in my 71 Delta convertible. I love that cam and yes it was USED! I bought the cam/lifters new 14 years ago. I put together a lo-comp 455/perfomer intake engine in a 83 G-body, 2:78 gears. This combo pulled hard, car was fast. No problems. Then I put a 4:10 posi in it, now a problem. I had put a hi-vol oil pump but still stock pan. This was my first Olds, I use to be into Chevys. Car was really quick now! Two days later he spun #5 rod bearing. I now learned about oiling problems. When removing a cam, I use a 18 egg container(buy your eggs in the larger box) I mark for each bank and the cylinder number, DON'T get them mixed up!! I then put this cam in a 350 Olds Bracket car, ran 13:50's. After a couple seasons I pulled it again keeping the lifters in order in a egg box. Two years ago I redid the 455 engine in my 71 and I re-used this cam for it's third life. It has a 2:73 peg/leg (one wheel) the cam idles good, just a little lope. It pulls hard, I shift it at 4800 rpm's. It has a Performer/ 670 cfm Holley, headers with torque tube/duals. I use stock type Crane bridges and dual springs, 120 lbs closed seat pressure but around 100 is fine. I have a stock oil pump on it. (hint, hint!) Watch that trans. I have the Switch pitch 400's in the 98's and I love them. Turquiose 98's is on a manuel switch. At the dragstrip I leave the line in hi-stall, at the 60' light I click it to low stall. Good luck, Ken

[Deltarocket]

Originally Posted by Kennybill

I had put a hi-vol oil pump but still stock pan. This was my first Olds, I use to be into Chevys. Car was really quick now! Two days later he spun #5 rod bearing. I now learned about oiling problems.

What exactly caused the spun bearing ? Did the high volume stock pan have anything to do with it ?

[64Rocket]

delta

because of the high volume pump will suck the stock pan dry. the oil returns in the heads can not keep up with the oil flow. you need to use a heavy duty pump with a stock pan or a high volume pump with an 7 or 8 qt oil pan.
The heavy duty oil pump is the one with the 1/4 " thick plate on the bottom. the standard one has the factory type tin plate.

Gene

[Deltarocket]

Originally Posted by 64Rocket

delta

because of the high volume pump will suck the stock pan dry. the oil returns in the heads can not keep up with the oil flow. you need to use a heavy duty pump with a stock pan or a high volume pump with an 7 or 8 qt oil pan.
The heavy duty oil pump is the one with the 1/4 " thick plate on the bottom. the standard one has the factory type tin plate.

Gene

Under what conditions does it dry the pan ? On a big block chevy, this was also a problem, but only on sustained high rpms.

[64Rocket]

Delta


Pretty much like you said. Sustained rpm will do it. 1/4 mile blast will do it. I would say sustained 65/70/75 miles per hour cruise down the freeway may do it also. If you have a oil gauge you will see pressure fluctuations as you drive at high speed.

Gene

[Kennybill]

The 4:10 rear-end was the "stick-in-the-eye," it "lived" when the 2;73 gear but even then it was border-line. The 4:10 let the engine "wind-up so much faster, pumping oil up to the top of the engine faster than it can return. I am a firm believer of using a stock pump unless all-out race with 7/8 Qt pan. Even the Olds engineers knew they had an oiling problem thats why the Toro had an extra qt oil pan and windage trays. Stock pump/stock pan is fine for a "regular" Olds with factory road gears. If you are going to race it then you have to take the next step or two in upgradng your oiling system. I have a habit of over-killing, my 98 has a 8 qt pan/main oil galley restrictors and a hi-vol pump, over-kill. Ken

[Deltarocket]

Even on a small block chevy, which I'm very familiar with, one takes all the precautions possible. One is using a high quality paint, on the top of the heads and lifter valley, the other is porting around the return oil passages between the heads and the block. Looking at a typical oldsmobile head, I can see room for improvement with a porting tool.

One thing about the Olds engine. You have to keep that passage on the heads clear, especially on high mileage engines. Gunk seems to settle there, which would greatly limit how fast the oil can flow back down to the pan. Also, if you have an emissions (EGR equipped) engine, take great care, as these tend to create a good amount of carbon gunk between the intake and the lifter valley, which eventually finds its way to the oil pump pick up.

[Oldsguy]

Interesting point about the paint. Over at R.O.P. as we all know, they are all about performance. I remember reading, perhaps more than one thread, about the oiling problems of the Olds engine and how to overcome the weakness it had. One person suggested painting the internal passages of the oil return in the heads AFTER hogging them out. Of course, some people disagreed but when I read that it was totally foreign to me, had never heard of that before. I haven't done that as I have a street Olds and never top 4500 or maybe 5000 rpm so I don't worry about it. Like Kenny said, Olds knew about it and did what they could to prevent it for "STOCK" engines.

[88 coupe]

Hi all,

That "high quality paint" would be Glyptal. Been using it on all my rebuilds for several years.

The oiling problem is there because the engine was designed to power luxury cars at highway speeds, not for racing.

Joe Mondello developed his modified 455 rods to address the issue and, in street applications, they worked well up to 5500 RPM with the bearing clearances he advised. Those increased clearances were the reason for using the high volume pump.

More side clearance on the rods will accomplish the same thing, and the crank grinder can open up the main/rod bearing clearances at the same time. How much will depend how the engine will be used.

Norm

[Oldsguy]

Hi Norm,

Good to see you here again. Welcoming your knowledge and experience.

[88 coupe]

Thanks Oldsguy,

The site is far easier to navigate than when I first visited.

Norm