• Welcome to the new SAOCA website. Already a member? Simply click Log In/Sign Up up and to the right and use your same username and password from the old site. If you've forgotten your password, please send an email to membership@sunbeamalpine.org for assistance.

    If you're new here, click Log In/Sign Up and enter your information. We'll approve your account as quickly as possible, typically in about 24 hours. If it takes longer, you were probably caught in our spam/scam filter.

    Enjoy.

Camshaft Comparison

JConstable

JConstable

Donation Time
All,
I am about to send my camshaft out to Delta Cams for a regrind, in speaking with them I proposed the KB grind (suggested by others on the site), but the individual at KB suggested the KC grind. His rational was that the KB resulted in a relatively rough idle and maximum performance at the mid and upper rpm range. In contrast the KC provides a slightly smoother idle and maximizes performance in the lower rpm range. I am thinking that I will not be throwing the car around the track or tearing up the interstate, but will mostly be around town and drives on smaller roads where quickness may be more enjoyable than top end. The complete engine picture (which is likely to influence cam choice) is anticipated to finalize at Vizard modification, reground camshaft and Bill A.'s headers. Any thoughts, comments, rants, or raves regarding the KB vs. KC grinds?

John
 
jumpinjan

jumpinjan

Bronze Level Sponsor
I'm not sure, maybe JimE might know.
I never noticed ANY difference in idle characteristics from the factory 1725 cam to the KB. Remember, the stock cam is a pretty hot street cam. I used the KB cam in the Tedder project race car and later replaced it with their wilder cam (D9) and it still idled well but with more top end (it was fun to drive).
Jan
 
Alpine 1789

Alpine 1789

SAOCA President
Diamond Level Sponsor
JConstable said:
All,
I am about to send my camshaft out to Delta Cams for a regrind, in speaking with them I proposed the KB grind (suggested by others on the site), but the individual at KB suggested the KC grind. His rational was that the KB resulted in a relatively rough idle and maximum performance at the mid and upper rpm range. In contrast the KC provides a slightly smoother idle and maximizes performance in the lower rpm range. I am thinking that I will not be throwing the car around the track or tearing up the interstate, but will mostly be around town and drives on smaller roads where quickness may be more enjoyable than top end. The complete engine picture (which is likely to influence cam choice) is anticipated to finalize at Vizard modification, reground camshaft and Bill A.'s headers. Any thoughts, comments, rants, or raves regarding the KB vs. KC grinds?

John
Click to expand...


Interesting. My engine is similar to yours (Vizard modified head with +60 pistons), as are my driving needs. When I discussed this with Delta they recommended the KB, which I have now had for about 6 years. I don't know anything about the KC, but I can tell you that while the idle is rougher, the difference is pretty minimal. The increase in power is definitely in the mid band, but I get to enjoy that in around town driving. You don't need to be racing or on the highway to notice the difference.

But, as I said, I know nothing of the KC and your mileage may vary.
 
RootesRooter

RootesRooter

Donation Time
With the KB cam and a Vizard-ized head, my V has much more pull even at low rpms. The 'gap' between 2nd and 3rd disappeared!!
 
A

Armand4

Donation Time
Issue 7 of the Alpine Marque, available on this website, has a chart on page 30 which lists lift and opening/closing figures for various cam profiles, including factory grinds, the Isky SB-2 and Delta's L2.
Based on this chart, it would appear that the stock 1725 cam is quite a bit hotter than the stock factory cams for the 1600-- in fact, it's a longer-duration cam than the "Le Mans cam" for the 1600. I'd think that the 1725's greater displacement would make it easier to live with at low revs than a 1600 with the same cam.
John, are you running a 1600 or a 1725? And Jan, do you recommend different camshaft grinds for each engine?
 
JConstable

JConstable

Donation Time
Hmmm, I guess that I could have been a bit more informative on my original post - it is a 1725. As for the idle issue, a bit of roughness is not a problem, but I have a very limited comparison. The car was functional for only about 2 months before discovering very poor compression (~100 lbs), then popping a head gasket and later upon engine dismantling a very worn cam. It may have been that the engine was pretty rough to begine with and that I'll never notice any real change - it may even be smoother. Additionally, since first gear tops out so fast having more mid range capability is likely to be more important (per Jim S) than low range. Thanks for the input! John
 
jumpinjan

jumpinjan

Bronze Level Sponsor
Armand4 said:
John, are you running a 1600 or a 1725? And Jan, do you recommend different camshaft grinds for each engine?
Click to expand...
For my Lemans 1600 engine rebuilds, I have been using the Delta "L2" which is their equivalent to the StageII cam that came in the Lemans.
When I drove Ian's Harrington 3 years ago with my rebuild & L2 cam, it was awesome. It felt so damm good. (Now, remember Ian had 40-DCOEs with decent jetting on his Harrington)
For all other 1600 rebuilds, I use the KB cams, just like my 1725 rebuilds.
The engines don't care what cam you put in them. Also, I highly recommend to upgrade to the KB cam, from a stock 1600 cam. That's about the best money for performance in the 1600.
Jan
 
JConstable

JConstable

Donation Time
The KB it is!, the cam is boxed, addressed and ready to ship. I thought I'd go KB over KC, but a bit of information from those in the know is always helpful. Thanks to all who contributed. John
 
alpine_64

alpine_64

Donation Time
John,

Not sure why nobody is saying this.. but before you send that cam..

box the rockers up aswell.. delta will resurface them.. they will be as shot as the rest of the motor.. and if you dont sort them you will never get the lash right.
 
Jim E

Jim E

Donation Time
Just wondering did Delta say why they sugested the KC over the KB grind? Those guys are pretty smart when it comes to cam grinds. For me the KB grind jut shifted the power band a bit upward and seemed to deliever more power overall. Not very lumpy IMO, even the D9 did not seem very lumpy to me. Actually I really like the D9 grind but it is just a bit much after a while the KB seems to be the best all aroud street grind.

Yeah I would send the complete rocker assemblies and the lifters to Delta along with the cam. They do very nice rocker work.
 
JConstable

JConstable

Donation Time
All, Thanks for the rocker reminder, the lifters are already in the box. As for the KB vs. KC (per Jim E), their rational was that the KB resulted in a relatively rough idle and maximum performance at the mid and upper rpm range. In contrast the KC provided a slightly smoother idle and maximizes performance in the lower rpm range. As most of the driving will be around town with forays into the mountains I was thinking KC, but realistically more driving time is spent in the mid and upper ranges where the KB is excels, hence my settling on the KB. John
 
puff4

puff4

Platinum Level Sponsor
OK, so I'll resurrect this thread because I just spoke to Delta and need some collective brainpower.

I am looking to build a docile, comfortable 1725cc runner for my wife and kids to drive. Nothing lumpy, and they don't really care a hoot about ultra-performance... indeed, that might be a turn off. What matters most is a nice smooth idle, good pulling away torque, comfortable cruising and decent gas mileage.

So... I talked to Delta. They confirmed, as you guys have noted, that the KC is a wee bit lumpy, and that the KB is somewhat smoother, but still a little lumpy. They then mentioned something I've not heard here - a "250S" grind, and said that might be the best option for what I'm looking for.

Anybody heard of this grind, and any feedback as to how it performs?
 
Jim E

Jim E

Donation Time
Have not heard of that grind. So the KC is a step up from the KB or a cam between the KB and the D9? What are you thinking to put in/do to the motor?
 
puff4

puff4

Platinum Level Sponsor
Pure stock, Jim... or as close as I can get it. Ideally, it would run like it did off the showroom floor. Standard pistons, minimal head milling, standard valves, no Vizard mods, etc. The only change would be Pertronix ignition, a 3-row radiator and electric fan, for reliability.
 
R

RootesRacer

Donation Time
puff4 said:
Pure stock, Jim... or as close as I can get it. Ideally, it would run like it did off the showroom floor. Standard pistons, minimal head milling, standard valves, no Vizard mods, etc. The only change would be Pertronix ignition, a 3-row radiator and electric fan, for reliability.
Click to expand...

I would try to talk you out of the pertronics.
IMO you are better off (and more accurate too) going with a crane XR700.

If you mill the head, at least make up for the loss in volume by deshrouding the valves. Going beyond 9.2/1 makes no sense unless you plan to run race gas.
 
SIVAllan

SIVAllan

Gold Level Sponsor
RootesRacer said:
I would try to talk you out of the pertronics.
IMO you are better off (and more accurate too) going with a crane XR700.

If you mill the head, at least make up for the loss in volume by deshrouding the valves. Going beyond 9.2/1 makes no sense unless you plan to run race gas.
Click to expand...

The Holbay (H120) engines produced 9:6:1 on street gas...

?
 
You must log in or register to reply here.
Top