Currently have a cam with the following specs in a 2004 Z06 :

Pat G Comp Cam 234/242 .601/.605 on a 111LSA.

What do you think of this cam for mainly street use ?

I having had the car for 6 month and can say that it is a pretty wild cam, the car idles really rough, very little power at low RPM, surges and not very streetable so am thinking of going with another cam and Stage II heads at the same time.

Suggestions for a different cam for street use as a daily driver ?

LS6 engine has been stroked to a 383 and has LG long headers and stock heads which have been shave to increrase compression. New pistons, springs, oil pump etc.

Thanks

 

Have you dyno tuned it yet? That's not a huge cam, and you should have very strong bottom end. How about detonation? When you stroke the motor, and shave the heads, the CR may be pretty high.

 

Yes, it has been dyno and street tuned, has 11.1 compression and makes 431hp 444tq.

Very little bottom end power and looking for other options so am surprized that it should make gobs of power low down in the RPM range.

 

Still searching for the answer....googled this :

The 111lsa should be left for extreme street drivers or racers IMHO.

Is the 238/242 .609/.615 on the 111lsa going to be too big?

That is a VERY big cam for a stock 346. Huge. 18 degrees of overlap at .050. Assuming 4 degrees of advance, DCR of only 7.84. It will be very soft on the low end and should be shifted at 7000 or more for best results.

That cam will be a dog below 4K RPMs unless you get a good set of heads to "match up" with the cam.

230/234 .592/.592 111 LSA - 2200-6400 RPM
Choppy idle. Good mid range and top end power. Minimum 2800
stall and 3.42 gears for F and Y body. Minimum 3200 stall and 4.11
gears for B body. Comparable to Comp 306 cam.

Ai 234 / 242 - .575/.580 - 110 LSA Primary Operating Range: 2500-6600rpm
This grind is best suited to 383 rebuilds with 11.0-12.0 compression. Lopey idle,
fair drivability with gears & tuning. It produces excellent mid-range and top-end with
peak power at approximately 6500rpm. Ideal for budget street/strip 383 rebuilds
with 3.73+ gears and 2800rpm+ converters.

 

My old cam had a DCR of 7.5, and it was only a 228-232@112+5. Tons of low end, and pulled hard to 7k. It had +6 deg. of overlap, IIRC. This was on a 346, and peak TQ was 432. I really think you have a tuning problem, or maybe somebody drilled your TB blade. What cc are your chambers?

 

I installed a MS3 cam (238/242°) on 112° LSA in a 346 with 5.3 ported heads, and after spending quite a bit of time tuning it was perfectly streetable. Before you throw in the towel, see if you can find someone to get that tune dialed in better.
Also if you are running an automatic transmission, what stall do you have?

 

What cc are your chambers?
Stock LS6 heads

Also if you are running an automatic transmission, what stall do you have?
Its a Z06 - manual 6 speed transmission.

 

In your first post you said the heads were milled to increase compression. If this is true, and your pistons are not relieved, the compression may be much higher than you think. This wouldn't cause your poor performance in lower rev range, though.

 

just put a Patrick G cam in my car. 231/235 .617 .620 on a 112+4
has stock heads and even a non ls6 intake. pulls real hard and has plenty of low end grunt. surging is not bad and easy to live with. i have a mail order tune by ESC and i like it. i also think tunning may be a factor.

 

cam is too big for street use. Patrick is very very good at what he does, However, if the primary use is on the street, a smaller cam is needed.

220/224 or 224/228 lift should be UNDER .600 or even under .590 and for street use 1800 to 6000 rpms range

 

It seems you're pretty sensitive about drivability - as am I. The cam you're running is bigger than tha one in my 427. Your cam has 16 degrees of overlap and if you're sensitive, no amount of tuning is going to make it run perfectly. As a rule of thumb, the less overlap the smoother the car can be made to run. It make make less peak power but if chosen correctly can have better average power - which is where it's at. Look for a cam with less overlap like a 228-234 114 +2 which has 7 degrees of overlap.

Check out this calculator to see how duration and ICL affects overlap.

http://www.wallaceracing.com/overlap-calc.php

Good luck..

Kevin

 

Thanks.

I'm not particularly sensitive, but, this cam is just too radical for street stop and go traffic.

 

It's a pretty large cam IMHO for a street cam But it should be tunable to idle smoother and be more street friendly---
What does it idle at when warm ???
Does it want to die when coming to a stop ?
Do the idle and surging issues appear when 1st starting up COLD only ??
ONLY when warm ?? or both ??

I suspect the LT headers are a huge issue as well--LT's require lots of tuning time as they typically make the eng run rich in closed loop (PT) operation--- If the car was only DYNO tuned then they most likely didn't do and driveability tuning which has to be done on the street under normal driving conditions
If it were an A4 it becomes more difficult to resolve these issues---however with a 6 -speed deffanately doable--

 

With a 383, and that much compression, It should be tunable to run fine on the street. I agree that it's a bigger cam than I would have, but lots of guys have gone even bigger than yours. Tuning! Or it was installed wrong.

 

What does it idle at when warm ???
About 850 RPMs

Does it want to die when coming to a stop ?
No

Do the idle and surging issues appear when 1st starting up COLD only ??
ONLY when warm ?? or both ??

Both, anytime under 2,000 RPM's in ANY gear, it is ruff.

Its been tuned on a dyno and I took it to COW for a street tune and to fine tune it, helped some but it is still ruff below 2,000 RPM's.

It now has 15,000 miles since the build and stroked to 383.

 

Did you check to see if some bozo drilled the TB blade?

 

850 should work--
When COLD you can adjust the low RPM and idle issue by LEANING down the " commanded fuel in open loop normal " table--In the lower fuel use areas say up to around 2000 RPM's the stock Commanded AFR is way RICH because of your LT's -- Stock is usually around 13.0- 14.0 here I had to lean mine down to 16.12---in order to trick the ECM to actually get it back to the 14.68-- range
COW has a great reputation-- When making changes to correct these issues and they tuners make changes--they do it all in 20-30 mins---However--unless you let the fuel trims and ECM "learn out" some before each change and settle down you'll always be chasing your tail-beause you make changes before it's had a chance to learn out--learning takes 50 or so miles of normal driving--

 

Patrick G knows more about cam applications than you or I will ever know!

I disagree with your cam selections for a 383 LSX engine. The cams that you spec out are mild by 346 standards and would be considerd small by 383 standards. The poor performance of a cam (car) is not entirely due to the specifications (grind) of said cam. From what I gather this combo has not performed from day one...other factors such as tune,installation,mechanical/electrical issues could also play a large part in the performance/driveability issues.

My 383 combo. Eagle crank,H-Beam rods,and JE -2cc pistons. GMPP 243cnc milled 61cc heads with Comp 921 valve springs = 11.3:1 scr. Cam Motion 241/245 .645 .633 114+4 along with numerous other after market parts that are not revelant to this dicussion. The combo made 482/442 on Liverniois Motorsports dyno with small SLP tuned headers and a ported 78mm FAST intake...a better header/intake set up could have possibly made that magic 500 rwhp.

The engine idles at 900 rpm with no surging or any other throttle related issues and the low end grunt is super. I drive this set up 3000/5000 miles yearly and consider it to be relatively mild mannered for street use. The McLoed Street Twin and the M12 tranny also help greatly in stop and go traffic.

 

I have a 231/243 .617.623 118lsa makes ton of power down low and pulls very hard up top.
Drivability is perfect. It gets better gas mileage.
Its all in the tune on the drivability. Lobe separation has something to do with it as well. Wider lobe separation better street driving characteristics, gas mileage ect.

Had a 224/224 .644.644 113.5lsa in my Ws6 and it drove like crap, eventually ran to lean and popped two pistons. Like I said its all in the tuner, if he dont know what he is doing your f**ked. Make sure your injectors are big enough for the cam you want to run.

 

Wow..I have not seen a cam with those numbers (231/243, .617/.623 & 118 LSA). That really sounds interesting. when you say you got good low end power, how low are you talking. I would be interested to know more about that cam. please hit me with manufacture. is that a custom grind? my current cam is 226/224, .576/574, 112LSA. matched with 215 AFR's. very nice lope, decent pull starting at 2700 rpm but only up to 5000 rpm. i would like to go bigger but not sacrafice too much streetability.