What do you think of this cam ? http://www.jegs.com/i/Comp-Cams/249/...oductId=760004 May be putting a non roller block in my car. 180 cc heads, Miniram 10.8:1 compression.


Comp Cams #249-12-366-4
"XFI" 268 Hydraulic Flat Tappet Camshaft
Chevy 262-400ci 1955-98
Lift: .520"/.515" w/1.6 Rockers
Duration: 268°/280°
RPM Range: 2000-6000

 

.......... Spend a bunch more for a retro-roller cam ... you'll be glad you did ... If its a stroker go with the 280 XFI ... ditto .................

 

What ever cam you choose,
I would make sure its a Hydraulic Roller or Solid Roller.
Not for any Performance reasons but for long term reliability issues....

They have taken all the "Zinc" or Zinc Diasulphate out of off the shelf motor oils local store bought.
You can Use Shell "Rotella T" or Devlon Diesel engine oil, they still have some zinc left in them.
But the amounts of Zinc in diesel oils have been greatly reduced last few years too to base minimal ASE standards.

Without Zinc in motor oils with a hydraulic flat tappet or solid flat tappet camshaft equipped engine, the camshaft lobes will wear severely in short order along with all 16 lifters.
Blame the EPA, their scientific research showed that Zinc in motor oils were prematurely plugging up catalytic converters after 100,000 miles.

You can buy specialty motor oils with high Zinc concentrations like the good old days like from Comp Cams, Brad Penn, and others.
But I think it is just a matter of time before the EPA cracks down on racing specialty manufacturers too.

No Zinc, all flat tappet cam motors wont live long till cam lobe failure.
With a roller camshaft engine, zinc in the motor oil for long camshaft lobe life is not an issue.
Roller cams have less peak ramp nose opening pressures than a comparable flat tappet camshaft profile.

Was a good move GM made in the 1987 L98 Corvettes.
Hydraulic Roller camshafts.
Someone there back in 1986-1987 probably read the hand writing on the wall...........EPA and more EPA. lol

I love flat tappet cams too, inexpensive to purchase and have been around for over 100 years.
I think they make near equal power comparable profiles in 98% of applications VS a similar roller profile.
Have used them both style of camshafts for racing.
Maybe 5-10 hp difference where a similar profile roller cam has slightly more HP.
Not enough to notice on the street.

But Zinc has been on the way out for the last 8-10 years in all store bought motor oils.
No Zinc and flat tappet camshaft lobes are guaranteed to fail within camshaft break-in periods to within 3,000 miles of No additional zinc fortified engine oil added after say an Oil Change.

When a camshaft lobe(s) fail, all the hardened or chilled cast iron debris gets circulated throughout the engines oil system.
Oil Filter does not catch all the microscopic shrapnel and the oil bypass valve in the sbc engines filter housing adapter is not reliable, bypass foreign material through.
Main and rod bearings, crankshaft journals, piston skirts, cylinder walls, valve guides, and valve stems die quickly with cast iron shrapnel present in the Oil.
Like tiny razor blades chewing up everything rotating and sliding inside of your engine.
Blame the EPA again.

Brian

 

I understand the issues with flat tappet cams. This is a $$$ issue. A new roller set up will cost about $4 -$500 more.

 

I have a xe-268 w/ a carb and am very happy with it. Very good city manners and you will know when you floor it.Not a "serious" horsepower cam but lots of torque and good power in the middle range.

 

.......... I speak from experience ... perhaps the oil companies have responded to the plight of the many performance enthusiasts who have "wiped" lobes off of flat tappet cams ... myself included ... But two reasons come to mind : there is a significant difference in the valve opening rates roller vs flat and this equals power ... And , I personally know what the aggravation expense is worth for changing cams in a C4 ... If you must ... Valvoline VR-1 Racing Oil has added ZDDP to help fight premature wipe-out ... and good old STP has plenty to help make up the difference ... I use both as added insurance with my retro roller cam ............
........... The real issue with using flats vs rollers ... i.e. OEM ..... is that engine speeds have slowed significantly related to vehicle speed due to overdrive trannies and 2.59 rear axle ratios in an effort to lower emissions and increase fuel economy ... C.A.F.E. ratings mandated by the Feds ...... what that does is reduce the internal splash oiling of the cam ... so even the best case oils are not being provided to the camshaft in necessary quantities because of the slower rotation of the crank , rods , and oil pump .............

 

Oh I know........$$$$$$$$$$$$$$......

A friend just put together a SBC 416 for dirt track racing.
We are going racing again in 2 weeks here in Illinois.
He has spent $9,000 + so far for entire New engine build.
Only thing used is a 1 season raced Little "M" small Journal block.
He has shaft rockers this year.
He is down to getting the money together for $400.00 Isky Tool Room Gold valvesprings.
He is crying the money blues too$$$$.

But they are paying out good this year for the top 4 people coming in after 1st place.

Are goal of course is get 1st place.
We will see.

Brian

 

The Mobil1 15/40 racing oil does also if that helps anyone.

Q, why use additive with a roller cam whats the benefit?

 

Where do you buy Mobil15w40 racing oil at Ron in CA?
Is it a chain store?

Zinc additive must help prolong Roller cam lobes also ?

It was only a few years ago in Crower Cams & Racing equipments main catalog,
Bruce Crower no longer recommended synthetic oils be used with racing roller cams.

He recommended only Kendell Racing Oil be used.

Was told that sometimes synthetic oils are sometimes too slippery,
The roller lifter wheels would no longer roll around freely on the matching camshaft lobes.
Instead they would skid across the camshaft lobes at very high racing speeds.

I don't have a Spintron to do camshaft research so who knows?

Brian

 

Thats pretty much what I'm looking for. If I was buying a roller, it would be a Hot cam. Specs are not that different. This is my daily driver. Thats why it does not have a stroker with big flowing heads and cam.

Oil choice is a bit of a dilema.

 

"Shell Rotella T" 15w40 would be my 1st choice of motor oils to use with a Flat Tappet camshaft.

I have seen Mack, Peterbuilt, Caterpillar, Kenworth engines make over 700,000 miles without Overhaul.
They are leaking oil of course all over by then.
But the engines still carry anywhere from 50psi to 80 psi @ 2,000RPM's.

Some built in the late 1970's.
Still running without an overhaul ever.
Owners Methodically used only Shell Rotella T diesel engine oil.

Has similar weight to old straight 30 w oil from the 1960's- to late 1980's.

In a SBC with .002" - .0025" on the main and rod journals running oil clearence and camshaft Journal running oil clearence of .001"- .0025" you will be just fine using Shell Rotella T.
You will have at least 60-70 psi hot oil pressure at 2,600 RPM's.

Shell Rotella T is available at all Autozone stores, Oreileys,
If along I-80 Intersrtate like here in Illinois, available at any Large truckstop.

 

Kragen auto parts think its called some other chain name now

I cannot find Kendall racing anywhere here that was my favorite.
Used Mobil 1 10/30 on solid roller motor from the start no real feedback as it didnt have enough miles on it to see about wear.

 

Google for any posts by UDHarold comparing voodoo 268 to comp XE 268. Here's one for example.

http://speedtalk.com/forum/viewtopic...2986aaff62b524

 

Yes Kendall Racing oil was a great oil to use.
I have not seen it around for sale in a few years now.
I bought in the past from Winner's Circle Speedshop in Joliet, IL.
No one bought it but me.
So they quit carrying it. lol

My late buddie that passed on liked Kendell oils also.
He told me that Kendell oil proprietary formulation was specially developed working with Indy car racing teams and their mechanics.
From the 1950's to the 1990's.

If you can find Kendell oil still I would not be afraid to use it.
The nice thing about Dino motor oils, the premium brands, they have no expiration date or shelf life.
So if you find a Case or 2 of Kendall Racing Motor oil in your Viscosity like 30w or 20w40 that has been stored away for 10 - 20 years....
Its still as good as the day it was manufactured.

Blow the dust off of each bottle and pour it into your engine.

All oils are not created equal like billions of people believe.
They don't race. Have never driven a car to over 100MPH.
Most can not even figure out where the engine oil dipstick is on their engine these days.

Sad.

Brian

 

The voodoo 268 is a great cam but if you want to go w/ 1.6 rockers be aware of the extra lift/duration, can't be sure you won't kiss a piston.There are a lot of ways to get some zinc into your oil(gibbs racing) and it doesn't sound like you want to build a 1/4 mile terror.

 

My vote is for the CC503.

 

I ran that exact cam with the HSR,Partriot heads,1.6rr's all last summer and was very pleased with its performance on the 350. Idle quality was nice, had a nice lope to it without it being overwhelming. I think you'll like it.
I know I have a couple fo videos out there while driving with it.

http://www.youtube.com/watch?v=VgAEVN0sVE4

 

I ran an XFI cam like that years ago, but was still listening to old geezers at that time and runnign a Holley 750. Needless to say it sucked(fuel mostly), so I can't really say whether it's a good cam or not. Since then I have heard bad things about Comp's cams going flat, althought they've likely fixed that.

I wasn't willing to spend the money on Retrofit stuff either. I used Comp's Break In oil, and am now using something called Classic Car motor oil, looks like relabeled Delvac to me. 400 miles or so and no problems.

I went with a Jones cam, just to be different, in my Monte SS with EFI connections 24x system, with LS1 coil on plug electronics. IT's using a Pro Flo Xt intake, Afr 187cc heads, 11:1 compression, thru a 5 speedTremec.

I chose a 280/280(228/228@.050) with .528 lift w/1.6 rockers. 112 LSA on a 109 centerline. IT has good driveability, quite responsive, kinda dead below 1600 RPM i.e. doesn't like 5th gear much anymore. Makes this curve on an AWD dyno, haven't tracked the car yet

 

Thanks guys. Off to do some reading.

 

Nice video. Any ET numbers ? I'm running 12.80 at 110 with my ZZ4 cam.