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Why so small? Just wondering why you splurged on the aluminum heads then. Just sayin
These are not small cars, nothing small at all and and who splurged? Not quite sure what you want to hear. This reply rings in as nit picking on this end. Why are you being so petty? "Just sayin"
Apparently you got some bad info, and I'm not nit picking.
There are more ways to make good low end torque than using a small cam. You could've made more hp at the same time.
Glad to see you stepped up to the good heads. I just think you short changed yourself on the other end that's all. No disrespect intended.
Apparently you got some bad info, and I'm not nit picking.
There are more ways to make good low end torque than using a small cam. You could've made more hp at the same time.
Glad to see you stepped up to the good heads. I just think you short changed yourself on the other end that's all. No disrespect intended.
Bad info you say, why don't you enlighten me oh Wise One, if no disrespect was intended then what was the point of your original reply? Nothing but cinicism, then again that is more and more of what seems to go on here at Classic Oldsmobile.com. I'm sad to say. More HP you say, tell me oh "wise one" when have our Oldsmobiles ever been about making top end HP? Oh yeah aluminum heads are only necessary with BIG cams otherwise, one wasting their 💰 , can you explain that one please while you educate me in engine planning 101.... thanks
Bad info you say, why don't you enlighten me oh Wise One, if no disrespect was intended then what was the point of your original reply? Nothing but cinicism, then again that is more and more of what seems to go on here at Classic Oldsmobile.com. I'm sad to say. More HP you say, tell me oh "wise one" when have our Oldsmobiles ever been about making top end HP? Oh yeah aluminum heads are only necessary with BIG cams otherwise, one wasting their 💰 , can you explain that one please while you educate me in engine planning 101.... thanks
Very nice build I'm glad to see someone build a 425, cutlass is just mad because you didn't order your cam threw him.
That cam is small for 425 ci, period. That is similar to the Edelbrock small block performer flat tappet cam in a roller. I realize it looks like it is going in a big car with tall gears but still very small. The whole point of a roller is aggressive ramps.
Alright Guys,
The Olds engines were intended to make mega torque but not necessarily as much horsepower mainly because you don’t spin these engines as high as others. This is due to many factors, not the least of which is that the BB Olds uses a monstrously heavy rotating assembly that includes a 3.00-inch main journal crankshaft. Basically, these engines are intended to run at 5,500 rpm and below. You should not treat a BB Olds like a small-block Chevy unless you spend big dollars for quality rotating assembly parts. A long-duration camshaft is intended to increase the amount of time the intake valve is open to help engine breathing at higher engine speeds. A longer-duration cam also means the intake closing point occurs much later than a shorter-duration intake lobe. If you think about how a four-stroke engine operates, the cylinder cannot begin to compress the air and fuel until after the intake valve closes. .... I'll be running a small carb too.....
Alright Guys,
The Olds engines were intended to make mega torque but not necessarily as much horsepower mainly because you don’t spin these engines as high as others. This is due to many factors, not the least of which is that the BB Olds uses a monstrously heavy rotating assembly that includes a 3.00-inch main journal crankshaft. Basically, these engines are intended to run at 5,500 rpm and below. You should not treat a BB Olds like a small-block Chevy unless you spend big dollars for quality rotating assembly parts. A long-duration camshaft is intended to increase the amount of time the intake valve is open to help engine breathing at higher engine speeds. A longer-duration cam also means the intake closing point occurs much later than a shorter-duration intake lobe. If you think about how a four-stroke engine operates, the cylinder cannot begin to compress the air and fuel until after the intake valve closes. .... I'll be running a small carb too.....
Absolutely, the 260 through 403 is also very different. Longer intake runners plus the flat valve angle means a flat torque curve and good fuel economy despite antique chambers. Look at the cam Cutlassefi ground me for my 9 to 1 Olds 350, 75 less CI. It is right at 9 to 1 with lousy 2.78 gears. I wanted good manners, idles at 750 rpm. What compression ratio do you have? The factory cam may have had similar duration but less lift. The advertised specs are 210/216 with lift designed to work with stock heads, just very mild. Your 67? Delta 88 is very nice by the way. We are not trying to be insulting, your rides look really nice.
Last edited by olds 307 and 403; September 10th, 2017 at 06:42 AM.
I'll "bite" on the torque question. I would guess a narrow LSA but to narrow and you'll have low vacuum. I'm right in the middle of this pissing contest. For a heavy street car that is hard to get better gearing I would prefer to be "under cammed and carbed" vs too much. For the cost of rebuilding iron heads one might as well bite the bullet and go aluminium heads. You've gone to a roller camshaft and Harlen Sparpe rockers, nice upgrade plus no more cam break in problems. I'm a build for torque, shift at 4800 rpm, not trying to set any National Records, guy. So I understand your build. Then on the other hand, there will always be a "better" camshaft to use. Everyone has an opinion. Harrold Burkshire (sorry if misspelled) could have picked the ultimate camshaft but he's passed. The Oldsmobile hobby needs younger guys to keep new products and availability of present products so I would hope people consider Cutlassefi if they are in the market for Oldsmobile upgrades, engine builds etc. Please stay away or a least read up before using the famous name California vendor. I assume this engine is for your 1967 Delta. What gears and purpose are you using your car for?
cutlass is just mad because you didn't order your cam (threw) him.
I expect this from you, bad spelling and all.😉
Kennybill- the answer is how efficiently you fill the cylinder. That's when you'll make peak torque, no matter how and when you do it. That's why blower applications have such a flat torque curve, it's being filled even past the peak of intake efficiency. Thanks for taking a shot.
So a small cam and carb does NOT guarantee you'll make good low end torque. You still have to fill the the cyl efficiently in order to make the best available torque. There are other factors but according to the op all that doesn't matter.
Op- there is a lot of knowledge on this site. It would've behooved you to tap into that. It may have made your build even better. THAT'S my point.
You totally misinterpreted Mark's (Cutlassefi's) input. He, as well most people on this site, wondered why such a mild cam? Especially with the more costly and the higher potential of the aluminum heads. Small was in reference to the cam not the car. Mark is highly respected by the overwhelming majority of the Oldsmobile community. Sends many hours on the phone helping people with their questions and problems. Never a sour or nit picking tone. He helps whomever asks. "Wise one" yes, disrespectful no! He has busted his butt helping people, even straightening out other peoples mistakes/ bad workmanship. There are lots of Oldsmobile experts and craftsman on Classic Oldsmobile. Most are willing to past on their experiences and hard earn lessons. I have read thousands of thread inputs, and yes there are occasions of utter disagreements. There are even feuds between strong personalities, or competitors. All in all, CO is my favorite, "go to" site for Oldsmobile information. Great bunch of guys, including Mark Remmel, (cutlassefi)!
Compression ratio you ask? Nice try "307" ,do you really think I'm going to offer up any more info on my engine build after the abuse I took here on cam choice.... I'll keep to myself thank you....serving up no more ammunition��
Now now, don't paint everyone with the same brush. I didn't knock your build. I understand how hard it is beating these "dead horses." I'm talking about 1965/1970 B/C bodies that no one makes tube headers and upgrading the gears are like finding hens teeth. I asked about your goals with the car such as just street or some dragstrip use? What rearend gears and what exhaust? My 1967 98 is 461ci ported iron big valved with H.S. roller rockers. Toro exhaust manifolds with 2.5" pipes. Best gears I could find were 3:08 posi.
September 9th, 2017, 09:26 AM
