|02-09-2005 06:05 PM|
|Lthompson||Ill agree, i really dont think i can make 500 horses with the smaller heads and those cams, but like i said, im just trying to get as close as i can. AFR got 460 with the 280 magnum, im trying to get at least that if not a little more. I really dont want to try to drive a car with a 3500 rpm stall too much, since right now i run down the highway between 3000 and 3500, im really wanting right around 3000 at the most. I called Comp today, and the rep i talked to recommended the XE284 for the application, which is what i planned on in the first place, but, i emailed them too, so i can get another reps opinion. and you are pretty much right, i want the baddest car at the drive in, or at least a respectable car at the drive in. anyway, thanks again for the help.|
|02-09-2005 05:19 PM|
I honestly don't think you'll make 500 horsepower with one of those cams. You are going to need something a little stiffer than that. If you do that, you're going to need more gear ratio (at least 4.10s). If you want to stick with a hydraulic comp grind, the old 292 Magnum would be good or the XE294. You'll easily top 450 horsepower, but to attain 500 I think you will need more compression and a more race orientated cam (so much for streetable). You will definitely need a loose converter, I'm leaning towards about 3500 stall speed.
It will be a bullet, but "streetable" will be a vague term indeed.
You want the baddest car at the drive In from what you are describing.
|02-09-2005 02:07 PM|
|Lthompson||I dont really plan on driving this car very far. No more than 50 to 100 miles. and i wont drive it that often. It wont have AC, it will have power brakes with a vacuum canister. I would really like to run a 2800 to 3000 stall. Im having it professionally built By a guy who builds dirt track race motors so everything will match up right. It will have around 10.5.1 compression. I would honestly like to get as close to 500 HP and 500 FT LB as i can. I already have the rearend and tranny to handle it. With those heads, AFR got 460 HP and 515 ft lbs, with the 280 magum, with 9.5.1 compression. I would like to get a little more hp than that if i could. Right now i think its a toss up between the magnum 286 and the XE284. I honestly wish they made an XE that was right between the XE284 and the XE274. HOnesly im wanting a steetable strip car that i can actually drive to the track and be a stoplight terror that will fry the tires whenever and wherever i want. Thanks again.|
|02-09-2005 01:00 PM|
Im going to assume this is to be something fairly low maintanance & reliable, you want to be able to take it anywhere, rather than just local jonts on Sat. nights. If so, if it were mine heres where Id be.
My first choice would be Cam Motion #131-4210 225/225 @ .050
.465/.465 110 LSA
If you really want Comp cams( thats fine) my choices would be :
270H: 224/224@.050 .470/.470
XE268H: 224/230 @.050 .477/.480
275DEH 219/229 @.050 .462/.482
These are all with 1.5 rockers (Id sell the 1.6s personally)
with those heads & your application I think any one of these would work great. If your after strickly a weekend stoplight to stoplight terror, than Id have a couple differant choices, but these grinds will work nice all around
|02-09-2005 12:04 PM|
THE GREAT AND POWERFUL NAIRB SPEAKS
Let me just say that although I am not a professional, I play one on TV, and my broker IS E.F. Hutton, and we all know what happens when he talks.
Part of the fun of building your engine is picking a grind yourself that actually works.
I don't think there really is always a perfect camshaft for each given combination, because slight differences in cam design will change slight characteristics of overall engine performance, maybe you want to run the A/C when it idles and you have power brakes.
Alot of novices who pick their own cam usually wind up over-camming their engine.
It's always best to err on the small side, you'll usually be happier.
With the wealth of information on the internet, and various compression ratio calculators, and dynamic compression calculators, as well as the very good information the cam manufactureres give you with regards to an individual grind's characteristics on their web site, , it's not too hard to pick out an effective cam as long as you are honest with yourself concerning your car, and you are willing to do a little research.
Most of the cam grinds that have been quoted in this thread are street performance grinds. Most of them would probably be suitable to use, depending upon gear ratio, and intended use.
The Comp 280 Magnum would be a good baseline cam to start with. If you want more top end, drag orientated stuff you are going to maybe choose a hotter grind, if you are more interested in daily grocery getting, maybe you would choose an XE268 or XE262, you want more, maybe the XE284 (if comp cams is your choice), There are tons of other manufacturer's grinds that will do the trick.
Once you leave the street hydraulic realm, and start getting into race-specific stuff, things change quickly, and you'll need to make sure you are running enough static compression to match radical cams, along with the proper valvetrain, like heavy duty valves, springs, making sure you have good rocker studs, etc.
No rocket science here.
I would suggest picking your own grind to the best of your ability, then checking with some cam companies and see how close you were in terms of cam choice to what they recommend.
|02-09-2005 06:16 AM|
|willowbilly3||I always recommend calling the manufaturer and using the cam they set you up with. You are making a compromise and it is your own judgement call how far into the poor mileage/unstreetable realm you want to lean.|
|02-08-2005 09:51 AM|
This morning I called Comp cams for a off the shelf cam recommendation on a circle track engine I planning for the 2006 season.
The basics are
Dart little M 4.125x3.62
Dart pro 1 heads
2250 pound car
5.83 to 6.50 gear.
They service rep punched a few keys and rattled off a part No.
I looked up the number on the web site.
Comp 280Magnum on 110.
Profesionals always know best?
A closer cam would be a custom grind around 265/270 @.050 and .550/.575 lift solid lifter with 1.7 or 1.8 rocker.
|02-08-2005 06:38 AM|
A waiter in a restaurant knows how to cut a piece of pie but does not have the slightest idea of how to make one, or a tomato picker don't know how to make tomato soup.
There are allot of pros on this board that knows how and what part is needed in any combination. This Board is for questions and ideas of what other's have used, and recommend.
If the Guidelines for posting were followed 75% of all the questions have been answered already and no use in posting anything else, as the manufactures have a tech line for problems.
I have talked to a few of these reps from the cam companies and they go by the book given to them and allot of them NEVER built a complete motor, and get paid minimum wage.
Wow what a professional.
Maybe the expert cam grinder should make some recommendation's.
|02-07-2005 07:34 PM|
Well I once made a custom cam for a Briggs and Stratton with a TIG welder and bench grinder, does that count???
The three cams listed are very close in size and the differences between the three will not be too much. The XE274 or the 286H would be the best picks in my opinion. Flip a coin or decide on driveability vs WOT. You know your driving habits and terrain more than anybody else.
|02-07-2005 07:22 PM|
And I have cut camshafts.........in the past.
I did not design them........just cut them........
And I stand by my statement.........
They will do a LOT better job than most anyone here..........Because they are professionals.
How many here work for a camshaft company?
|02-07-2005 06:26 PM|
Notice he is not a Moderator ON THIS Forum or a professional or even knows who is one on this Forum.
I would recommend a CompCams Magnum 280H .
Maybe because I run in the sportsman class in top alcohol dragster, Im probably wrong because its not a Pro class.
|02-07-2005 04:50 PM|
I am amazed
|02-07-2005 04:39 PM|
Those motors do have hyd roller cams, so your motor will not make quite as much hp, but my main point was to compare the size of the cams they were using not necessarily how much hp they were making.
They could be inflating the numbers, and so could all of the other magazines that get similar numbers. I don't have any reason not to believe them though until I see something on the contrary.
|02-07-2005 03:06 PM|
You wouldn't suppose AFR would inflate their numbers for argument's sake would ya?
Don't believe much of what you read. Even if you read in ten different places.
|02-07-2005 03:04 PM|
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