i am thinking of using the comp cam xtreme camshaft for my 355. i couldnt find much info on it on the comp cam site, so i was wondering if you guys heard anything about it. i'm also wondering how big of a cam can be used with a stock converter.
my engine is 355 with edelbrock e-tec 200 heads, speed demon 750 mech, rpm airgap..
i think have a stock converter.. i know i need a big cam to take advantage of those heads and carb.. I was thinking 274XE.. will that work?

Thanks, Matt

------------------
73 Camaro LT 350/355

You could get away with a 274 but I'de go with the 268(actually I did go with the 268 and I love it). I think that the 268 is the largest you're supposed to go with a stock converter but I could be wrong.
Donnie

IMHO, I think you're right about needing a good sized cam to take advantage of those heads. Didn't Car Craft or Chevy Hi Performance have an article recently with the e-tec 170 and the e-tec 200 heads? They ran them both on a 350 SB, used a fairly mild cam, it might have been the X268 cam, and the e-tec 170 heads ended up outperforming the e-tec 200 heads. If you want to use a stock converter I'd say the e-tec 170 heads and a X262 cam would work pretty well. If you want to use the e-tec 200 heads you probably should use at least the X274 cam and at least a 3K converter.

[This message has been edited by Bob_T (edited 12-06-2001).]

you shouldnt need a 3k stall with the 274xe, a 2500 would be better IMO. i say skip the XE line and look into the Magnum line. the XE line has steep ramps and causes alot of noise, it sounds like a solid! its also harder on valve train components then the other lines. 270H or 280H magnum would be a good choice.

Finally! someone else who has the ETEC 200 heads. Hey matt,I have a question for ya. Are the header bolt holes on your ETEC 200 heads lower than the center of the exhaust port? Mine are and I cant find headers the fit,what headers did you get? I also VERY MUCH agree with the magnum cams over the extreme cams with those heads. The reason is that the ETEC heads have excellent exhaust flow,in fact some of the best flow numbers of all aluminum heads.So,that said,you dont need the extra exhaust duration and lift of the extreme line,the magnums make awesome torque curves from what ive seen. I bought the 292 magnum for my ETEC 200 383 stroker. You could probably get away with the 280 magnum with a stock converter,but you should stick with the 270 to be safe,just get some 1.6/1 rocker arms to get some more lift. One other thing,why dont you just get yourself a stall? I mean,you spent all that money on nice heads and stuff,why not take advantage of it? Just my opinion,either way it will be pretty damn stout,good luck and thanks for any help on the header thing...

CamaroNOTcamero,

I was wondering when somebody was going to pick up on a possibl;e problem w/ the EX line of CC's cams.

They talk about stronger springs and being noisy! So for all that crap I'm just curious what the lift of a EX274 will be if you drove it just like an old -151, 350hp/327 cam??

Isky always made "balls-out" hydraulic cams w/ their Mega line that had SOTA ramps and tweeked timing to max. them out. But they are single pattern cams.

You know, thats why I like solid cams, you get to use good springs with them, as well as being noisy and you can rpm them to the "moon" or until your springs give up!

I really don't want to go backwards and have all the attributes of a hydraulic cam that thinks its a solid, but NOT!!! IMHO. pdq67

Actually your are wrong! If you think you need a big cam, it won't turn on fully until after your torque range and converter has already locked it will be sluggish from the go and then open up. People never realize that they have to match there cam with there torque converter and rearend. If to high or to low. It can cause overheating in the tranny and the engine. Unless you have real deep gears and change your torque converter you will NOT be to impressed. If everything is stock I recommend a 215 degree or 218 degree @ Half duartion. Otherwise yu won't have that neck snapping torque you crave. Good luck.

------------------
It is better to burn out than fade away

thanks for the ideas guys
I havent put all of it together yet, and i havent figured out the exhaust side of it either. thats a big problem for later probably, but i will keep you updated when I figure something out. i'm hoping for my old headers of unknown brand to bolt on, but we'll see.

The reason i looked at the XE was it supposed to have a more plateau of torque instead of a peak curve compared to the magnum line.

also, would it be worthwhile to try a roller cam? whats involved with setting up a roller?

Thanks

------------------
73 Camaro LT 350/355

Very interesting comment on the noisy aspects of the XE line. I had the XE274 in my 400SB and loved it although the valvetrain noise was annoying. I re-adjusted the valves several times and it never helped. I just lived with it and never thought about the cam ramps being the culprit.

The cam is an excellent cam IMO. I ran it with the RPM heads and it was a great street cam. I switched to the hydraulic roller version during a recent rebuild and it's even better - and much quieter.

The switch to a roller is a bit pricey but easy. You'll need roller lifters, new pushrods, roller rockers, and the roller cam. Add in the cam button and a new timing chain cover and it gets expensive. But, it makes excellent power.

------------------
Scott
'69 400SB, Richmond 5-speed
www.geocities.com/sdenning1 (http://www.geocities.com/sdenning1)

I cant say that I have noticed my XE268 being noisy. It is certainly quieter than the 266 energizer I was running.

------------------
'78 chevy truck-355, 9.4-1, vortec heads, XE268, vortec rpm intake, 750 edelbrock, flowtech headers and terminators.

'77 Nova-slowly progressing project.

'78 Nova-parts car?

'95 Lumina 3.4L DOHC 210hp daily driver

I have put tons of the XE series cams in, both the 268s and the 274s, hyd flats and . One poster got it right.....the 274 is just about all you can run on the street with enough vacuum and it needs a 2300+ish stall converter for autos.

Albeit a smiggin bit noisy, especially with steel valve covers,(the big alum ones are a better sound damper), the XE series produces more hp per cube than just about any other cam series on the street.

My wife's 69 convertible has the XE274 hyd and has a power band from 2200 to 6500. And it sounds soooooooo cooooooooool.

The XE268 is the furtherest you can go without a non-stock stall converter and it might need one if you have a heavy car and/or a real tall gearing/tire size.

The XE 268 makes more vacuum and a perfect street cam!

------------------
STEVE JACK
ConceptOne Pulleys and Brackets

I had an xe cam in my 355 with aluminum roller rockers, I didn't notice any noise and it ran great. you might want to check out comp cams new line of xe solid lift cams. I do not see them listed on the web sight yet or even in summit or jegs, you can call comp cams and they will send you a small 3 or 4 page catalog that has them listed and also other new products they have including their new line of "nostalgia" cams

------------------
67 RS
355, SUPER T10 4 SPD
9" FORD

PDQ67, i agree i'm going with a solid also, if its gonna sound like one, it might as well perform as one, and rev like one.
me and my brother installed a 268xe in his corvette, in a heavier car (3500+lbs) you'll need to change the converter, and we found that out. it also needs some decent gears. we're hoping to solve the problem by using a 2000 stall and a 700-r4(more gear) and he wanted the overdrive. it pissed me off to find out that we installed that thing and it makes a ton of noise(for a hyd.), and even though the stock converter was supposed to work, it made ther trans get awfully hot, luckily he doesnt drive the car much so we were alright.

I have a 383 with the XE 274 but don't have the engine in the car yet. I've gotta get some other stuff done first.
I noticed a lot of talk about the XE line being noisy. Exactly what "kind" of noise are we talking about. The reason I ask is that my brother has the XE 268 in a 355 in a 78 Camaro. The car runs great, sounds great and is VERY streetable, however we have noticed a noise that seems to come from under the intake about midway of each side where it bolts to the Vortec heads. It is more like a muffled "pump, pump, pump" noise if you know what I mean. He's been running it for several months and no problems.
Any ideas?


[This message has been edited by gjohnson (edited 12-09-2001).]

I just gotta!!! Heck, man!! Thats them little mice in there that turn the crank sucking air!!! Thats why they call it the "mouse motor". LOL! pdq67

As long as they keep turning the crank I guess I better not mess wid'em, huh!!

I have an XE274 in my 400sb and I have noticed that it is a little more noisy than most other cams, especially with the roller rockers. It annoyed me to death after I put the engine in, but I have learned to live with it. It does provide excellent performance though.

thanks for all the ideas..
I am really considering the 274xe with 3000 stall and prolly changing to a 3.73 gear.
I know some guy who says he has a couple of solid rollers he would sell me for cheap, could be worth a try. (but isnt that a whole new thread? hehe.)
I would not be adverse to running a vacuum canister to get away with a bigger cam if it helps the engine remain streetable


------------------
73 Camaro LT 350/355

Well we've kinda come full circle on this one, but the XE 274 is all I will put in a pure street car not only because of the vacuum, but also the idle qualtiy, and carbing gets funky with all the differing application ranges and the fuel milage really plummets!

Young whipper snappers will do anything tho....outta my league

------------------
STEVE JACK
ConceptOne Pulleys and Brackets

Just a note on this. I spoke to Comp Cams about using the dual pattern XE series cam in a 406sbc. They mentioned that it is not a great idea with higher compression ratios due to the added cylinder pressure these cams produce, thus increasing the likelyhood of detonation. Their recommendation was a single pattern magnum cam for my application.

I'm using the XE284 right now on my daily driver 383, with 10.7:1 compression......no problems.

------------------
383 Speed-O-Motive stroker kit with Holley 750DP, RPM intake,MSD6a box,World Products Sportsman II heads, ported and polished with 2.02/1.60 valves,64cc,TRW forged pistons with 10.7:1 compression, Comp Xtreme 284 cam,Crane pushrods, Comp Cam 1.6 full roller rockers,ATI damper, 40 series Flowmasters, 4.11 gears with TH350 and Hughes 3000 stall.

Tracy, are those the Sportsman ll Lite heads by any chance? If not, are you using an octane booster? The issue with me was stock GM 400 heads (882, 76cc) with a port/polish and 2.02/1.6 upgrades, Comp Cams didn't think that the XE was a good selection.

<BLOCKQUOTE>quote:</font><HR>Originally posted by Jim McGregor:
Tracy, are those the Sportsman ll Lite heads by any chance? If not, are you using an octane booster? The issue with me was stock GM 400 heads (882, 76cc) with a port/polish and 2.02/1.6 upgrades, Comp Cams didn't think that the XE was a good selection.<HR></BLOCKQUOTE>
Nope, iron heads,200cc runers and 64cc chambers. I had Ignitionman help me dial in the timing, and worked out to be 13 degrees inital,34 total and runs great on 93 octane,no boosters.I have heard several people using them in high compression motors.....


------------------
383 Speed-O-Motive stroker kit with Holley 750DP, RPM intake,MSD6a box,World Products Sportsman II heads, ported and polished with 2.02/1.60 valves,64cc,TRW forged pistons with 10.7:1 compression, Comp Xtreme 284 cam,Crane pushrods, Comp Cam 1.6 full roller rockers,ATI damper, 40 series Flowmasters, 4.11 gears with TH350 and Hughes 3000 stall.