235 vs 261 engines

[David_Hayward (RIP)]

I read recently that the 1953 (and presumably 1954) 261 cam was used in the Corvette 235s to improve performance.

I would query if the 1955-1962 Pontiac 'Astro-Six' 261 car engine derivative of the 261 'Jobmaster Six' truck engine had higher lift lobes? The car engine with its higher CR produced up to 152 bhp depending on year, which compares with from memory 135 in the truck engine.

[Alex Blair (RIP)]

Originally Posted by David_Hayward

I read recently that the 1953 (and presumably 1954) 261 cam was used in the Corvette 235s to improve performance.

I would query if the 1955-1962 Pontiac 'Astro-Six' 261 car engine derivative of the 261 'Jobmaster Six' truck engine had higher lift lobes? The car engine with its higher CR produced up to 152 bhp depending on year, which compares with from memory 135 in the truck engine.

Dave..
When I read this an old memory stirred so looked it up..
I don't think the 235 was recammed but know for sure that Duntov recammed the new 265V8 for '55 to a 3/4 race cam..
I had one..a 265V8..
It was super hot..
You had to have been there in those days..I was..
Read this..
http://www.islandnet.com/~kpolsson/vettehis/

[cletrac (RIP)]

Alex, speaking of having to be there, that engine that I put the solid lifters in was a 56 Chrysler 354 that I put in a 57 Plymouth 4 door hardtop. In the early 60s it was the coolest rig around.

[Alex Blair (RIP)]

Originally Posted by cletrac

Alex, speaking of having to be there, that engine that I put the solid lifters in was a 56 Chrysler 354 that I put in a 57 Plymouth 4 door hardtop. In the early 60s it was the coolest rig around.

Aye...
That Chrysler 354 engine was an early Hemi..I had the same engine in a '56 Desoto..
in Chatham,NB..in '64..and then another Chrysler screamer..a Red Ram V8 that I stuffed into a .59 Plymouth..in North Bay in '67..I had the 265 In a '56 Pontiac at the same time..Just couldn't stay away from that old iron..
But the hottest of them all Was a 361 Edsel engine stuffed into an'58 Ford..
had a 4 barrel on it that two men could get inside to adjust..
Couldn't keep transmissions in it til i finally put a four speed out of a '54 Merc 3/4ton..
Had to change the yoke on the drive shaft..had a course spline on that tran end and a fine spline on the diff end..but what a piece of work..No speed shifter but would it ever light up after we got rollin'//

[Barry Churcher]

In all my experience building engines for drag cars and owning a stock car I never did figure out what a 3/4 race cam was. 3/4 of what!
Barry

[Phil Waterman]

Hi

I just posted on http://canadianmilitarypattern.com/1...e%20Manual.htm the manual pages from the 1960 Chevy Truck manual. It includes the valve timing diagram and the valve lift information. Which you might find interesting.

Just for information sake my 235 has hydraulic lifter and my 261 has solid lifters.

Cheers Phil

[Alex Blair (RIP)]

Originally Posted by Barry Churcher

In all my experience building engines for drag cars and owning a stock car I never did figure out what a 3/4 race cam was. 3/4 of what!
Barry

Barr7y/...
You probably forgot more stuff than some of these young whelps with their souped up rice rockets ever will know...
Crane still advertises them..They run a little rough on the idle but come on when you give 'er...try one...good for the street..blow away some of those young whipper snapper at the lights..
Best $129.99 US you'l ever spend..

Crane #270-100172

Energizer 3/4 Race Hydraulic Flat Tappet Camshaft & Lifter Kit
Lift: .450''/.450''
Duration: 274°/274°
RPM Range: 1800-5800

100172 - Crane Cams Energizer Cam & Lifter Kits Details

Chevy 262-400ci Small Block 1955-98

*Note: In order to use these camshafts in 1955-57 265ci blocks, it is necessary to machine a small groove in the rear main journal of the cam to allow oil flow to the top of the engine.

**Note: Beginning in 1987, most of the V-6 and V-8 engines were equipped with hydraulic roller camshafts. There are differences in the block to accommodate a cam retention thrust plate and the anti-rotation mechanism for the lifters. These blocks are identifiable by bolt holes for a cam retention plate under the upper timing sprocket, as well as bosses and tapped holes in the lifter valley for lifter retention hardware. The camshafts on these engines have a step nose and smaller bolt circle on the front of the cam. An earlier model camshaft may be used in these blocks by using the appropriate timing chain set and adding a thrust button when using a roller cam.
1988-99 Chevrolet 305 and 350 V-8 engines (and some 1987 350 V-8 engines) use a different configuration camshaft core than the 1955-87 engines and cannot be interchanged.

ROUGH IDLE, MODERATE PERFORMANCE USAGE, GOOD LOW AND MID-RANGE TORQUE AND HP, MILD BRACKET RACING, AUTO TRANS W/2500+ CONVERTER, 2600-3000 CRUISE RPM, 8.75 TO 10.0 COMPRESSION RATIO ADVISED.

Grind Number: 274 H06
Operating Range: 1800-5800 RPM
Duration Advertised: 274° Intake / 274° Exhaust
Duration @ .050'' Lift: 218° Intake / 218° Exhaust
Valve Lift w/1.5 Rockers: .450'' Intake / .450'' Exhaust
Lobe Separation Angle: 106°
Max Lift Angle: 102° ATDC Intake / 110° BTDC Exhaust
Open/Close @.050'' Cam Lift: Intake - 7° BTDC (opens) / 31° ABDC (closes)
Exhaust - 39° BBDC (opens) / (1°) BTDC (closes)

[Alex Blair (RIP)]

Originally Posted by Barry Churcher

In all my experience building engines for drag cars and owning a stock car I never did figure out what a 3/4 race cam was. 3/4 of what!

Jeez Barry..I was so excited I forgot to answer your question..Here is the history..

compiled by
HARVEY J. CRANE, JR.
October 1, 1999

Ed Winfield made his first performance camshafts in 1914. These were motorcycle cams with individual lobes pinned to a shaft.

His first automotive camshafts were ground in 1919 when he built his first homemade cam grinder. Ed was 17 years old at that time.

Ed told me his mother gave him the money to purchase a used grinding machine that he converted to a cam grinder by adding a rocker table. This homemade cam grinder was used in his mother's garage to regrind Ford Model T camshafts into racing specifications.

Ed told me he first made only two masters, a SEMI RACE GRIND and a FULL RACE GRIND! He later made a third master that was more duration and lift than the SEMI but less than the FULL. He then used the FULL RACE master as an intake and the new master as an exhaust.
He called this new reground camshaft a THREE QUARTER RACE CAM! Ed said "It was three quarters of the way to a full race cam".

According to Dema Elgin, ED began working for Harry Miller at the age of 14 1/2 in the carburation department. Within a few months he was doing other machine work on the famous Miller racing engines. Harry wanted Ed to stay on with him and offered Ed more money. Ed was being paid .60 cents per hour and was offered .70 cents, but ED wasn't fond of Harry because he was like a dictator.

Ed quit grinding camshafts in October of 1969 after he finished a batch of Drake Offenhauser camshafts. That's 55 years of grinding cams!

[Paul Singleton]

I hope Crane Cams survives the economic crisis!

http://www.autoweek.com/article/2009...NEWS/902279984

Paul