raroz28

I am considering another cam. See my specs for my current cam:
226/231 560/568 @ 1.6 114 lsa.

I like my current cam through the higher RPM's, it seems like it never runs out of steam.

However I do not like taking my car that high (I go to about 6800).

Doing this last year I spun a rod bearing but that was a stock motor with 140k.

The engine is rebuilt and has ARP rod bolts now.

I just want something that has more power in the lower RPM's and makes power up to about 6500.

I want the car to run low 12's high 11's with a good 60' time.

I do like the smoothness of my idle with the 114 lsa

Give me some suggestions on some numbers I should look at. I do not want to call a custom cam builder just yet.

I do not plan on ever boosting this car so I want a powerful NA cam.

Any suggestions?

RamAir95TA

I'm thinking the 503 would suit your needs just nicely.

Bersaglieri

That's what I'm thinking, XE503. It's one of the best off the shelf cams. It'll pull to 6200-6400rpm with usable power everywhere. If you post up the advertised duration of your current cam and the ICL I could tell you how much you'll sacrifice, if any, in idle quality. Next step down would be the XE502 which makes gobs of TQ everywhere and has a tame idle.

What static compression are you running? What rear gears? How good are those "ported" heads?

-Dustin-

raroz28

Not sure what the rear gear is. I used to know but I have forgotten. It's a 97 M6 so whatever came standard with that.

The ported heads from what I understand are top of the line.





Some pics of the heads from 07 before I put them on the car...





I have a cam card I will have to upload some pics of it it has all the details on it....

raroz28

My cam sheet...

According to this, the ICL is 110.

raroz28

i had always thought the 503 is very similar to what I have.

What are the differences and how will that cam help me reach my goals better than the cam that I have now?

RamAir95TA

FYI I can't read a damn thing on those pics you posted of what I'm assuming is the head flow chart.

raroz28

Ok here are some new pics I just took.

The cam card I have is almost blank from age.

Mystery Bird

I ran the CC XFI 280 for a couple of years with good results in sig. It came on hard down low and never seemed to let up. Here are some video's of the idle and some track runs: MysteryBird1 - YouTube

Orr89rocz

Heads flow 248 by .550 then start backing up at .600? Not really a "top of the line" ported head casting. You'd want the flow to not back up on the bench to lifts much higher than .600 even tho you are running sub .600 cams.

But with that, I agree the 503 seems to be a nice cam. Wont be as smooth on a 112 as a cam on a 114 but it will make better mid range power.

Another cam to consider is the 268 XFI. Great little cam that makes good power and is extremely driveable although the lobes are abit aggressive and require good spring to control. 280xfi I've run in a friends motor and it wanted to go to 6500 rpm but had valve float. Needs good double spring 150lbs seat or higher and near 400 open to control but its a good cam, just abit big for what you need. Thats where the 268 comes in. Good bit smaller but still a good 350-370whp cam. 280xfi seems to be taxed at 400-415whp depending on the setup.

raroz28

I have seen many charts where they are only slightly higher at .600 than they are at .500. Most flow charts I have seen only go up to .500 and many do not show the .550 so I can not comment if it is unusual to back up or not.

What I meant by top of the line is the guy who did them. According to him it is not so much about the flow number as the actually flow and design.

The 268 looks smaller than what i have now. I do not really understand cam numbers too much. I had read a lot on it when I was doing my cam years ago but that information has long left my memory.

How would the 268 be better than what I have now?

raroz28

That sounds sick. Awesome times too, what rear gear are you running?

Orr89rocz

You said you didnt want to go to 6800 rpm which seems high for the 226 cam you have now. I'd expect it to be done well before 6800, likely 6400-6500.

If you want lower rpm, you go lower on the duration of the cam to bring power band back down.

RamAir95TA

Those heads by flow numbers alone are comparable to stock LT4 heads. They are okay but by NO stretch of the imagination are top-of-the-line.

Top-of-the-line ported stock castings flow upwards of 290+cfm on the intake side.

raroz28

I was of the impression that higher cfm did not necessarily mean better when it came to heads.

I know when I was dealing with turbo's I had turbo's that flowed at a higher cfm but made less power for the application. But like I said I do not know, I am only going by what I was told.

Edit: After doing some research, I am thinking I am correct in believing that more CFM does not mean better by any stretch. It is about flow and velocity, which is what I was told in the past. It has been years so I am very rusty with all of this. I knew some of it at one time but it is long gone with the wind.