cscollis

Ok, I was running a 216/220 .525 .532 on a 114 with my 1.8 rockers and I changed to a 224/224 .563 .563 114 cam with the 1.8 rockers and lost 3rwhp up top. I did pickup HP from 3500-4400 then it mirrored my previous cam. Air fuel was 12.8 to 1 across the board.

I am thinking my cats my be screwed, hell I cant explain why I did not pick up any top end.

Any suggestions?

SSean

possibly need tuning? You monitor A/F on those runs?

Jabroni

If you're on stock heads, you may be at a plateau. There's nothing else you can do about it if that's the case.

jmX

Back when I had some crappy heads, I could put in all sorts of huge cams and I never gained rwhp. At the time, I didnt have the facilities to re-tune after each one. I imagine if you could tune your car, the bigger one would probably make a bit more.

Damian

iTrader: (89)

Without a retune, those #'s don't mean anything. Every single cam swap should be retuned IMO. You'll pick up more....

Josh

Ragtop 99

iTrader: (7)

You went to a higher lift & more aggressive ramp profile with the cam switch. Are your springs up to the challenge?

Was your converter locked on both dyno runs?

SouthFL.02.SS

2 things...

1. Tuning helps (as mentioned).
2. 1.8 rockers on a 224 .563 cam? I hope it's not XE-R.

99 Black Bird T/A

iTrader: (4)

With retune you might gain some.

I didn't think 1.8 rockers were recommend for cams with ~.560+ lift...but I could be wrong.

I don't think the stock heads are going to gain much with even more lift. Seems like its time for heads to me.

distortion_69

iTrader: (20)

Any valve float? I've heard of even a tr220 with 1.8's breaking blue stripe 918's.. I'd be scared as **** to use with the tr224.

taqwache

i would also bet on the 1.8 rockers. i never liked going with a higher ratio then stock. if i wanted more lift i would just pick a different cam. put on the stockers, get it tuned and get another dyno run on it. then let us know.

jrp

iTrader: (16)

1) tune
2) go back to the stock 1.7 rockers or invest in some good dual springs

your lift with the 1.8's is .596.

JoeDirt

Isnt that WAY too much lift for stock heads anyways ??

jrp

iTrader: (16)

no, but its killer on springs. the g5x3 i assume has more lift then the x2 and the x2 has .595/.609 lift and they both work on stock heads. dual springs should be used when going with such a high lift and aggressive ramps of a cam like that though.

01_SuperSlow

iTrader: (7)

I'm gonna bet on the 1.8 rockers as the problem also.

4thGENRETARD

1.8 and above 0.050 lift is a NO NO . Go back to 1.7's , good springs, Tit. retainers and hard prods then tune. You'll be amazed.

SouthFL.02.SS

I'm not sure if the overall lift values are so much the culprit here, just that the TR224's aggressive ramp rates are not supposed to be used with 1.8 rockers, as per TR's website. The thing is that to begin with, we don't know if he's running a TR cam, or simply a cam with similar specs.
The TSP 231/237 I use has .598/.595 lift values, but with a bit less aggressive ramp rate. It runs fine on stock heads and Comp 918s.

Ragtop 99

iTrader: (7)

My point is that the lift is OK but weak springs could be causing float or valve bounce.

Beast96Z

iTrader: (21)

In most cases the 224/.561 lift cam is the comp XE lobe. 224/.581 is the XE-r. I agree that the 1.8's are throwing things out of wack. If the 224 cam needed .596 lift, they would've ground it that way. Check the spring pressures and put the 1.7's back on.