I'm just about ready to pull the trigger on a set of Brodix IK180, 64cc heads for my 76 L82 4spd w/ 3.55 rear. The intended use of the car is a weekend cruiser for some full throttle fun without going too crazy with drive-ability issues. The previous owner had the motor blue printed to L82 specs, there is about 10K miles on the rebuild. I've had the car for 2 years and the motor runs real strong for a 76 L82, no issues (good candidate for a top end rebuild). I was all set to just order the Comp XE274 Cam along with the rest of the parts when I had a moment of doubt and started researching cams again. I started looking at the VooDoo 268 cam and wondering maybe that would be the better choice. Then I thought about vacuum signal with the head lights etc.... and looked at the Comp XE 268 because I hear pulls a lot more vacuum. What's your guys experience been here? Any advice? What about the Comp L79+ cam? It's on a 112 LSA with similar duration to the XE274. Anyone run this one?

CS NOSTALGIA L79+ Hydraulic Flat Tappet, Advertised Duration 276/283, Lift .468/.462, 112 LSA

 

I went with the Comp XE268H. Our specs are a little different but I am very pleased with it. My car initially had 3.08's and I changed to 3.55's like you have and it totally transformed the car. Below is a link to a post I made that tracked the dyno results of my build up. The cam change added 60 rwhp.

http://forums.corvetteforum.com/c3-t...mp-xe268h.html

 

Cliff built the carb for my Firebird. He definitely knows his stuff. Talking to him when I was buying a carb kit for the Vette is what made me think maybe I should look at the L79 cam. He thinks that some of the older cam designs are still worth while if you aren't looking for max HP necissarily.

 

Impossible to talk cams without knowing the trans and gears. What RPM range do you spend most of your time in?

I think you're in the right range for lift...we can sort out the vacuum signal once we have more info. The L79 cam is going to make less power throughout the range than one of the Xtreme Energy cams...no reason to use an "old skool" cam with new design cylinder heads.

 

Borg Warner 4spd and 3.55 gears. I like to get on it when I drive. Most trips are with in 5-10 miles of the house and it's a 4 spd.

 

The Comp XE cams are an older line of cams than the Voodoo cams. When Lunati decided to do the Voodoo line, the goal was specifically to beat the XE line of cams.
Since they were able to compare the new Voodoo grinds vs the XEs on the dyno before releasing them, you should have a pretty good idea which cam line has the potential to perform better for you.
Based on what you are wanting from the car, I would probably stick with the Voodoo 268.

Here is a nice video of a 76 Vette with a 268 Voodoo cam

The exhaust on this car makes it sound a bit "nastier" than it sounds in some others.

 

For about $300 more, you could go retro-roller. More HP, much better chance of survival, never worry about oil recipes, runs quieter, etc.

There's no way I'd purchase something from Comp's XE (flat tappet) line of cams today.

Go on this site or others and search "XE cam wiped lobe" and you'll be reading for days.

 

i have the xe 268 and it doesnt pull lots of vacuum, i have no problem with the lights but the vacuum is lower then i thought it would be and had to change the vacuum advance cannister....why not buy some of the books that have built engines with different components and tested them.....this gives you real world dyno results and the cost of parts, and its hard to argue with roller rocker technology

 

With 3.55 gears and a 4-speed, I think you've made a good choice with the XE and I'd stick with it. If you're concerned about vacuum, you could take one step down to the XE 268.

The XE cams are "near roller" profiles and they're great cams - I've used them almost exclusively for the last 5 years or so, building about 10 engines/year.

 

I would go roller cam without a doubt. If your dead set to use a flat tappet cam the XE274 is a good match for your flat top, 64 CC combo @ about 10 to 1 compression. A 268 duration cam may have issues running pump gas with a performance dist curve and that much compression.

Here is what I would choose since you can order the correct springs on your new heads for it, you are already going to buy pushrods and you will have good flowing heads that will probably give you an extra 40 HP with the higher lift and mure duration under the curve, pretty cheap HP and not a big cash outlay plus you can run regular oil and not worry about wiping a lobe:
http://www.compcams.com/Company/CC/c...?csid=159&sb=2

 

I can't see the slightly higher DCR being an issue at that CR; I've run 10.2 or better with that cam and iron heads with full advance.

Just one guy's experience

 

Why dont you download competition cams software, CamQuest

http://www.camquest.com/

 

Camquest is an older version of Desktop Dyno and gives wildly - wildly - inflated HP and TQ numbers. Fun to play with, but not much actual use.

I'm happy to run a couple of DDAs on the different cams if there's interest...

 

This just came up recently. Most of these cam companies will give you a part number for a varried LSA grind for a catalog cam, with less overlap for better street vacuum. The actual sale will still be through places like Summit or Jegs, but Crane did it for me several times. Also Crane makes Hi Intensity flat tappet lifters that bleed lift down a bit at low rpms, giving even more vaccum. I've had really good luck with this street build combo. Give the Crane tech line a call.

 

I was thinking that might be interesting to try. I see the comp nostalgia L79+ looks a lot like the xe274 but with less lift on a 112 lsa.

 

Billa,

If you wouldn't mind that would be great. Maybe the xe268 vs the xe274 w/my combo? BTW I'm running the XE262 in my Pontiac for about 8 years with no issues. It's doing what it should the car runs 13.8's on street tires with a 9.1 compression 400. I've got no issues with comp.

BTW is it worth looking at Rhodes lifters to try and boost up the vacuum?

 

I've seen that on you tube, this car sounds absolutely nasty.

 

Worked for me. Built a big inch street motor several years ago, and Crane fixed me up with a 114 LSA version grind of one of they're normally 110 LSA big catalog cams. With Hi Intesity bleed lifters and MSD multi spark ignition, idles pretty decent, and all the vacuum accessories work fine.

 

I have the Lunati 262/268 cam and it produces good smooth power.
Idles very well since I replaced the Q-jet with an Edelbrock 1411.

Perhaps I should of went with the 268/276 cam since I have ZZ4 heads and 1 5/8 headers and Performer manifold.

I have it in a 75, turbo 400 and "stock" gears.

The stock engine with 90,000 miles was a slug. The updated engine runs pretty strong and is very drivable.

No ridge in the cylinder wall at all, just a stain.
New rings, bearings and oil pump.

Ralph

 

I am running a CC XE274H cam in my 383. 13" vacuum @ idle. No problems with any vacuum accessories.