Opinion on 2 Crane hydr. roller cams diff. in criuze range

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kelley555

Member
Grumpy,it looks like you've used both Crane hyd. roller cam in different sbc engines.I wanted to get your opinion.Would you think there's a enough a cruizing range difference between these 2 cams. I have both Crane hyd. roller cams in two new blocks.I have a #119661 .538/.548 ; 230 dur. & 238 dur.; .900 bc in a std. bore 400 ci bow tie short block on an engine stand & the Crane #119691.548/.558 ; 234 dur. & 242 dur ; .900 bc in a motown 415 ci. long block for my 72 chevelle.Using my turbo 350;3.73 gear;3000 stall & I have a 25" tall tire M/T street slick. I was thinking about changing from a 25" to a 28" tall tire which will reduce the Rpm's from 2984 rpm's to 2664 rpm's at 60 mph chart.Would this swap cause the 415 ci.engine to function incorrectly at 60mph.Is their be enough difference between the 2 cams to warrant a cam swap.Both are on the stands,the 400 doesn't have a timing cover yet & the 415 I'd have to pull:the water pump; balancer; backoff & readjust valve train ;pull a Comp cam aluminum quick change cover.Possibly changing to the 28" tire changes the rpm's too low.I'm in the process of mocking up the aluminum radiator & pulling/testing the Ac evaportator core.Thanks Jr
 
if your going to swap to the 28" tire the milder cam(119661) will most likely be the better choice,and it should work marginally well with that 3000 stall and 3.73:1 rear gear,but I run a similar set up in my 383, and a 28" tires very likely to make the car run in a lower average rpm band than either of the cams are designed for with that rear gearing.
neither of those cams really likes to run most of the time under about 3000-3500rpm, so depending on your application , you might want to think about either stiffer rear gearing and an over drive transmission,or a different cam in a car built for cruising
why not call crane tech guys and get their input also
crane-386-310-4875
 
Grumpy,I called the Crane tech as you suggested.There not enough difference of 4 degrees duration between the two cams to make a difference .Basicly his opinion was to leave the bigger stick with the 415ci.The cam sheet shows a minunum rpm of 2800 rpm-6800 Mx. rpm for the bigger cam.He said with the cubes & Afr 195 heads the power band should move down some 200-300 rpm's.The smaller cam min. 2600-6600 mx. rpm with the 200-300 rpm less rpm band.So,I should be ok running a 28" tall tire reducing the rpm's.I guess for ultimate performance I should use more gear. 3.73 & 25"=2984 rpm's : 3.73 & 28"=2664 rpm's : Hughes 3000 stall should be tighter (2800 rpm ).Have you've ran both sticks in 383 or larger engines.Do you think it'll be ok & not labor the the engine.Later Jr
 
Ive run both cams in the past in my 383 sbc, with a 3000 stall and 3.73;1 rear gears in a 3500 lb corvette, both work, the milder cams a bit nicer in traffic and long cruises but like crane stated theres not a huge difference, personally I preferred the milder cam in my 383 sbc for daily transportation, but like cranes tech stated the extra cubic inches in the 415 will compensate some what.
each of us has or tolerance level for how a car drives and what were willing to put up with, and what were willing to ignore, personally I want the car to instantly and smoothly react to a throttle change, and Im more than willing to sacrifice a few peak hp while running n/a (non-assisted)if required running N/A (no nitrous) because Ive got a 200hp nitrous kit installed on the car if I want to stomp on the throttle, and in my case I seldom race the car, I rarely find the need to use the nitrous as the cars able to smoke the tires quite easily running n/a and the cars driven on the street 98% of the time.


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