This is a 454, 10.5:1 compression, large oval port heads (049's), th400 with 11" Breakaway converter and 4:11 gears in the rear. It is not daily driven. I have narrowed the choices down to the xe274 or the xe284. I'm just concerned that the 284 might have too much duration and the car won't perform at low rpm (below 3000). Thanks!

I don't know much about the xe cams i'm have a ultradyne 288/296f10, 255/263@50 612/630 lift dcr came out to 8.3 running 93 octane .Drives great on the street with plenty of punch.I heard Xe cams are noisy,my solid is pretty quiet and i,ve only adjusted it once in 6 months.Just make sure you use a cam big enough to get your DCR around 8 so you can run pump gas. graemlins/waving.gif

In my 418 I run a Comp Cams. Magnum 305H. It has no problem with low rpm performance. 305 duration 575 lift hyd. 10.5:1 Compression.

call Bullet cams ask for Bob Cook#662-893-5670
excellent service and 1 week delivery. if you want a Comp email me @igrinditshrp@netscape.net
I live in Lower Bucks and can maybe help you out.

The XE284 240/246 at .050, .574/.578 lift is whats going in my 506 stroker, but my cr is 9.5:1

68hotrod,
To keep this short, the engine builder screwed up and put the wrong cam in and is now on the hook to make things right. I'm sure he has a source and will insist (spelling??) that I go through him for the parts. Sounds like the 284 is the way to go! Thanks all for the input.

i have almost the same set up as you. i run the xtreme 274H. if this is primarily a street car i would consider running this cam. i think that while the 284 might make a little more hp the 274 will make more torque where you want it. i run sunoco ultra at 34-35 degrees and experience no detonation. good luck mike

JR70LS5,

You ever get that thing up to the track? I'm considering a solid next time around instead of a hyd. roller, but still not sure..

matt

With 10.5 to 1 you don't need a XE series cam..it might build up too much cylinder pressure..

Nope, never seen any track time and it's killing me! I want to install a drive shaft loop and do some suspension work before I start taking it to the track. Hopefully in the spring it will be ready.

Originally posted by rednecks70:
I have narrowed the choices down to the xe274 or the xe284. I'm just concerned that the 284 might have too much duration and the car won't perform at low rpm (below 3000). Thanks! Sir, the cam that will absolutely dominate either of those choices is the **New** Lunati BBC276/284F10. yes, it might take around 6-7 valve lashings to take a set and then the maintenance of the lash will be every 2500 miles at worse. The gain is that I bet you'll run near 120 in the quarter and well into the 11's. ( assuming everythign else is up to snuff - like those 049s having big valves, etc.)

The only other problem I forsee, is that if you do full power runs, the track official will require you to cage the car! graemlins/thumbsup.gif

You WILL NOT be disappointed with that cam. I run it, it's mint. power from mid 2000's on up. Sorry to confound your choices, but simply wnated to let you know that you might be leaving something on the table with those hyd cams.

I hear ya 427L88! I'm not in a good situation with the engine builder at the moment and I feel that changing my mind (from hyd. to solid) will cause serious problems between us. I have never raced before either so maybe running a low 13 or high 12 to get my feet wet might not be a bad idea. Did you call me "sir"? That makes me feel way too old tongue.gif LOL! Thanks for the info, I will keep that part number in my file for future reference.

OK if it has to be a COMP, then at least look at their solid XE cams, which are much more similar to the UD/Lunati. You have the cam already?

In Comp solids, the XS282S looks OK. The 280s ( NOT 282S), looks like they copied Harold's 276/84. That's part number 11-551.

Also look at this grind, 11-670-4.

If you're stuck on hyds, I would not recommend the smaller cam with 10.5:1. You WILL have a gas issue. A much better fit than the XE284 is, in my very humble opinion, their part number 11-314-4, grind # 280AH-10. I would break this one ( and ANY of those clackity XE gfrinds) on outer springs only.

Sorry to confound you. I hear ya on the Sir biz. I was an NCO. Call me Sir and it rubs the wrong way. I was just being courteous.

You should use the 280AH-10. Sure its a short track cam, but it straddles the difference between he XE grinds you mention, and hopefully, it doesn't S-L-A-M the exhaust valve down so violently as the XE's. It seems very much like the UD280/88 that mr 4 speed uses with great success.

MadMarv I haven't been to the track yet,I was supposed to go last month with my uncle,but ran into fuel starvation problems,ended up being the fuel sock in the tank.We are shooting for Nov. 1 now,i'll keep you posted! graemlins/waving.gif

Just to add a little, i do believe the XE line of cams "slams" the intake valve, not the exhaust valve. The exhaust profiles (at least on the HFT)are the same as the magnum series. That's right, off-the-shelf XE cams have XE intake lobes and Magnum exhaust lobes. As far as I know the Magnum series of cams do not have a valve problem closing the valves.

i currently run the xtreme 274H. the pistons are the KB#207(.250 dome). this is a ls6 replacement type piston. the heads have 2.19-1.88 valves and were cc'd out to 116. i did not measure how far down in the block the pistons are. am also using the felpro blue perma torque head gasket. I run a dual plane intake with the heat riser blocked. mallory unilite with stock curve and 35 degress total timing. carb is an 830 cfm holley dp. i use pump sunoco ultra 94. how can this be i have NO problem with detonation? with the engine in 3rd gear i can nail it and don't seem to be pinging. the plugs are a light chocolate. this is my actual experience and humblem opinion. but i feel the ultra solid would have been a better choice. good luck in whatever you decide. mike