I've got a carbed Z and I'm changing cams. I wanting a cam on a 110LSA but I haven't found any luck finding one. Where's the best place to have a cam ground with that lobe separation? Thanks in advance.

 

Try these guys, they do a lot of cams.

Combination Motorsports

 

You can order directly from the manufacturer and pay a premium or from a reseller and pay a bit less. Just tell them what you want. It will be a "custom" as none of the catalog LT1 cams are on a 110LSA, AFAIK. But there is really no difference other than that it won't be an "in-stock" item anywhere. At least with Comp, they usually have "custom" orders shipped within a week of getting the order.

Rich Krause

 

Thanks!! Any more suggestions??

 

Little note on LSA,

LSA is a byproduct of other camshaft specs and valve events(opening,closing), rather than a spec you should look for. Like this example, here a 110LSA doesn't say anything about a cam it could be WAY too much or WAY to little LSA for what you are running.

LSA is also the only cam spec that is in cam degrees unlike every other cam spec that is in crank degrees.

Bret

 

As Bret posted, this does bring up the question of do you really want a cam with a 110LSA. It would be a somewhat unusual LSA for a street small block. The fact that you are running a carb on your '93 kind of implies a race car though. Is it a hydraulic roller, solid roller, or what? Just curious.

Rich Krause

 

The car is still hyd. roller and I've run a cc306 for years, then a xe230/236, both on a 112LSA. The machine shop that's doing my new 355 said to try and find a cam on a 108 or 110lsa. Said I would be disappointed with a cam on a 112LSA. Cams are one of my weaker spots as I don't know all of the technical issues. Thanks for the info.

 

Ideally you want to have long durations if you want to tighten the LSA. Find out what your heads flow, cid of your engine, gears, and that type of information a cam grinder would want to know to be able to grind you a cam you want. Also, because the amount of cylinder pressure (blown motor) tight lsa may not be what you want.
To answer your question, I think the folks at www.Schneidercams.com should be able to help you.

 

Things have changed over the years.

Back when I first got into engines, the typical small-block chevy cam was in the 106-110 lsa range. Now everyone wants to go wider, which may or may not be the right direction depending on your goals.
Most people think wider lsa's produce more avg torque (all else being as equal as they can be considering the change in overlap area) but I don't know where that comes from cause I haven't seen the same.

The oem's most likely went this way to lower emissions. The trade off in avg torque vs cleaner idle was one they were happy to make. So, if I were an emissions-conscious guy, I'd look at staying with a wider lsa and not-too-much duration (more overlap). If power were more my thing, I'd go tighter, erring on the tight side.

This is from an article on the subject by David Vizard. If you want to read the whole thing you can go here http://www.engine-builder.com/index.htm

Go to search back issues, type in cam event and click on article #5. Check out the graphs comparing cams of differing lsa's.

The best way to cover this is to start from an optimum and see what we lose by first going too tight (a smaller number) then too wide (a larger number). If we have an optimally spec’d LCA for a race engine then we find that as the LCA is widened torque over the entire rpm band used drops off quite rapidly. For example, in a 350 SB Chevy, two degrees too wide can mean a loss of 20 or more ft.lbs. throughout the rpm range. On the other hand 2° too tight will have almost no effect on the output over the rpm range used while racing. If the LCA is too tight the motor needs to turn higher rpms before it comes on-the-cam and the idle is rougher. For a race engine then it is best to err on the tight side rather than the wide side. Because the idle quality goes as overlap is increased it is better to err slightly on the wide side if we are talking street usage. Here I am talking 2° off optimum, not the 4° to 6° and even 8° that is often seen. If you are installing such cams in commonly modified engines then you might want to consider upgrading your source of cam advice.

Good luck.

-Mindgame

 

I just experienced this issue .. My old cam was a 230/236 106IC, 110LSA... New one is a 233/242 111IC, 114LSA. I swapped cams in hope of getting something that would help w/ N2O. Figured I'd increase the duration a bit since I knew it would bring the peak power down some..... Unfortunately I lost ALL AROUND . Lost power throughout the ENTIRE powerband, and peak RPM's also dropped by 400rpms.

I just photo'd a copy of my two dynographs overlaying each other. Gonna post it up in a bit. Need to find a host for it.


Does someone have a tissue? LOL..

 

Mindgame has a good post

Yep one of the great wives tales of cam selection, I haven't seen it either.


Umm not really, higher durations and tighter LSA's mean more overlap. A street cruiser or a car needing to pass emissions would want to go the other way.

Really high durations on a street car might need a higher LSA to work for cruising around and to have enough vacuum to work the brakes.

Very good point! all of that has more to do with the LSA choice than anything else but the LSA is still a byproduct of the right camshaft!

Bret

 

I would give ISKY a call they are easy to deal with fast turn around and you do not have to wait an hour on hold to talk to some one. the last cam I ordered was a 217-225 with a 106 LSA
have only done limited driving with it so far but it seems to make a hell of a lot of power so far. I have it installed in a 1991 L98 freshened bottom end and Holley systemax heads and intake.
it idles at 750 with around 9-10 Inches of vacuum

 

Isky has some good off the shelf cams.

My custom cams can be made in a day or two if the core is there, and e-mail, phone and IM mean you can pretty much reach me pretty easily.

But I hear what you are saying, because most places take forever to get into talk to someone.

Bret

 

Thanks for all the replies, I called Combination Motorsports and they set me up with a comp xe233/236. Again, thanks for all the replies.