I'm going with a 227/233 560/569 on a 111 LSA. I don't want to rev above 6500 with a stock bottom end. How should this work out....

 

Guys,

These big duration cams are not making a hell of alot of HP, because the RPM range where they would be effective on a LT1 motor is in the mid to high 6000rpm range. Next throw a set of SE lobes on there and you can't control the valve float so that's why you are getting a high RPM drop in HP that is so big.

You would think that these 227+ duration cams would be good, and make a ton of HP over a 220-224 duration cam, but they don't. The reason they make any power is the overlap, not the duration, and at the same time they are killing their mid range TQ with all that added duration.

These reasons are why guys with the CC305 run so well.

It's also a good idea to look at the .200 duration as well as the .050. In the case of Hyd Roller cams that extra duration @ .200 means that most springs can't controll the valve over 6300rpm very well and the power just falls down hill. Throw a set of Comp R's at that and some more spring pressure and you will see some nice gains and the motor will run at higher RPM.

The LSA debate of 110 vs 112 and 114 is something to look at. The smaller LSA is going to help power, but the higher LSA is needed on the bigger cams just to get them to idle right. You can run a 110 or even a 108 on a stock cube LT1 easy, and a 110-108 on a 383 even easier, you just gotta not throw so much duration at it.

Bret

 

What Bret said! My mind wanders into forced induction (since that's been my thing for the last six years) if I don't conciously remind myself we are talking NA. The increased duration will be a huge benfit on a supercharged motor, but as Bret siuggests may be too much for an NA setup.

Still, all else being optimized, most of the NA cams out there have to wide an LSA for optimum power. You do run into potential idle problems as the LSA is narrowed however.

Rich Krause

 

Just so everyone knows, this 230/236/112 cam has much more potential than what's been posted in this thread so far!

Here's kmook's dyno sheet from 2 years ago when he hit 400hp with this cam on stock bottom end, ported heads, and true duals.

Also here's an example of the lope of the 230/236/112. movie

I think it's perfect for my street/strip car.

 

Isn't it the other way around?

 

no thats right.... the lower the lsa, the more the more the power moves up and the more it narrows.

 

I ran this cam on a 110 LSA for one racing season on a stock bottom end, and stage 2 head. Cam didn' really wake up untill 5500 RPM.. I was shifting at 6100, with a 700r4 and VIG. 4000 Torqe coverter. Ran 12:22 @ 112. Needless to say my stock bottom end did not like this combo.

 

Just a note on the XE230/236 camshaft:

RPM range 2200-5800, listed by Com Cam.

Here is a cam from TPiS that I am looking at for a 383 stroker:

ZZ-409 Hyd Roller:

Adv. duration 287/287, duration @.050 226/226, Lift .520/.520. 112 LSA. Lift is at 1.5rr.

Do you think this is a good street cam for a 383LT1. Does it have the potential for 400+ RWHP with LT1 ported heads, TB, headers, cat back, tuning. Using A4.

 

Not good at all. Ever notice how LT1 cams are almost always "split pattern", with more exhaust than intake duration? There's a good reason. The intake of an LT1 flows well, relative to the exhaust, especially on a street car with the relatively restricted exhaust system. So you need a split pattern cam for a street LT1.

Rich Krause

 

Thanks for the note, Rich. Yes I now noticed that.

The cam in my 355 right now is ZZ-9 Hydraulic Roller:

Advertised duration 282 287
Duration at .050 212 226
Gross lift .483 .520 with 1.5rr
Lobe separation 112

I am using Comp RR 1.52. I was thinking to keep my ZZ-9 cam when I build my 383LT1 but TPiS told me that I would gain 25 more HP with ZZ-409.

Do you see my ZZ-9 a good 383 stroker cam or is it small for the 383.

 

I am running the 230/236-112. It idles fine. In fact, I think it sounds fairly tame compared to a friend's car with an LT4 Hot cam. The XE series packs more 0.050" duration into the same advertised duration. For example, in terms of advertised duration (0.006" lift, the Hot cam is only 2 degrees less on the intake, and is only one degree less on the exhaust. But the 0.050" lift numbers for the XE are 12 degrees more on the intake and 8 degrees more on the exhuast. Given that idle characteristics are determined by the overlap and very low lift numbers, the fact that the idle of my car is fairly smooth is no surprise.

With Comp 987 dual valve springs on ported heads, the power does not fall on its face, even at the 6400 RPM redline I have set.

The torque curve is very flat, and stays above 300 ft-lbs all the way from 2000 rpm to the redline, and peaks at around 375. Horsepower rises almost linearly and peaks right at the redline.

I agree that a fatter torque curve is more suited to an A4, but the M6 is an absolute blast to drive with this cam.

BRAD

 

I think it would be pretty tame. But the ZZ-409 would not be my choice as a replacement.

Rich Krause