I have a 1986 T/A that I am building a 355 for. It has a TH350 with a 2800 conv. and 3.73 gears. The 355 has Hyper Flat top pistons stock rods with ARP bolts, Stock crank, Chevy phase II "bowtie" heads with 64cc chambers and a full port and polish job. Performer RPM intake and a 750 edelbrock carb. I have Hooker full length headers and a custom Y pipe with a 4 inch flowmaster turned down at the rear. This car IS NOT my daily driver, but I want it to be fairly streetable. My question is..... What cam do I want to use. I would like to have right around 400hp. I was thinking about a Comp 280 magnum, I've used it before and it was pretty good with some ported 882's. I haven't used any of the new Extreme energy cams, I'd like some input from someone that's had some experience with them. I'm open to anything that is not roller or solid lifter though. Thanks!!

Check out the XE268 from Comp Cams. Very nice cam.

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383 Speed-O-Motive stroker kit with Holley 750DP, RPM intake,Proform HEI dist.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.Powertrax NoSlip Locker

You don't think the XE268 would be too small? I was thinking I needed at least the next size bigger.

it should be fine as long as your heads were done right.it'll give your good torque on the low end and if your heads are ported right they'll follow through with the h.p..

The heads were done professionally by a well known shop. Will that cam with these heads make 400hp in my 355 with around 10.5 to 1 compression?? I am having them flowed next week to verify the work. What does a set of ported phase 2 bowties with casting number 14011034 fully ported (stage II) flow? I'll have numbers next week, but I'd like to know what to expect.

If you decide to go for the XE274H-10, you'll need somewhere around an 11:1 compression ratio (depending on how well your 882s flow). 10.5 might be a touch too high with the XE268H-10, if you want to run pump gas.

Hope this helps!

Big O Dave

these heads are VERY good production heads,BUT the compression ratio is going to get you. if you can't get a set of d-dished pistons then this is your only other choice,install the cam at 110 degrees and it might be wiser to go with the 274. if you bleed off low speed cylinder pressure you'll be able to get away with the higher compression ratio. installing the cam stright up(110) or going larger on the duration will do this.if you go with the 274 install it at 108 degrees. i hope you do know those heads are going to make your motor a little lazy on the low end ,they have 185-190 cc intake ports and have been ported.BUT it'll come in with a BANG around 3500 rpms! and yes it'll make 400 h.p. easy between 6250-6750 range. i hope this helps you sorry if it was a downer.
P.S. i just did a compression check for your motor with a stock deck height of 9.025 and a .043" head gasket you'll be around 10.2. go with either the 280 magnum or the xe268 and install the magnum at 108 degrees or the xe268 at 110 degrees intake centerline. it will come in hard around 3500 and your shift point will be between 6250-6750 rpms. this combo "should get you by" with pump gas and around 410 h.p.
head flow should be around 250 cfm on the intake and 180 cfm on the exgaust this is at .500" lift and measured at 28" of water. and these are estimated a little on the low side. HAVE FUN and keep us posted!

[This message has been edited by sldhd (edited 05-12-2001).]

[This message has been edited by sldhd (edited 05-12-2001).]

The XE274 is a great cam.

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67 Camaro, 355, Trick Flow G2 heads,RPM intake, XE274, TH350 with Hughes 3000, 4.10 posi

It kind of depends on what gear ratio you use. I had a 355 in my 69. It had cast, flat top pistons, 292 Comp Cam, a set of milled, double hump heads, 750 Carter AFB, Hooker headers, Weiand X celerator single plane intake, I also used a dual plane Weiand. It had a Muncie 4 speed, and a 3.31 posi 12 bolt. It was driven mainly on the street. I never had a problem of detonation. I normally ran 10-12 btdc initial timing. The car never missed a beat. I revved it to around 6500-7000 rpm, all the time. I could get about 10-12 mpg on the highway with 26 inch tall tires. I ran the eighth mile in the low 8.50's. I had the heads cc'd at 62cc. I was probably in the neighborhood of 10-10.25 to 1 comp. I normally ran 91 octane. I don't think you would have a problem running this sort of combo in your setup, except I would opt for a lower set of gears, such as 3.73. If you would want more torque, you could run a smaller cam, such as the 280 Magnum, or the 274 Extreme Energy. They would both run great with them bow ties, but those heads like rpm. I would run the bigger cam, with a lower set of gears, but any of those should work very well.

you didn't detonate because you blead all your cylinder presure off into the atmosphere with that bump stick.that thing had 244 @.050" which is huge for the street with an auto(thats what he wants),i'm not saying it can't be done but it would be fun to hit the gas and have a little torque down low to drive on. you probably would have run faster times with the magnum 280.my buddies 88 olds with the stock 3.8 would turn 8.6 in the 1/8. bigger is not always better,but it sure sounds better!i mean how many times do you drive down the street at 6000 RPMs? thats the only place a bigger cam will out do the smaller one,in this situation.

I ran a 280H in a half broken 350 for a year, and put it into my new rebuilt. It lopes nicely at 800rpm idle, and starts pulling at 1500, and explodes at 3000. I love it, it's very streetable with a dual plane manifold. When I get the motor broken in, I'll see how far up it iwll breathe. I just got this thing started Saturday, so I don't know if it will even hold together. But it sounds real good for a daily driver. We'd all like to shoot fire out of the pipes at the stoplight, but I can't drive like that every day.