JimMueller

iTrader: (9)

I had a 377ci LS3 built in 2010 and installed in my '98 Z28. Obviously this is a Mustang dyno so the operator said to expect a Dynojet to read about 15% higher.

Basic mods for my graphs:
Fast Toys 85mm lid
100mmm MAF with flow straightener
Nick Williams 92mm TB
Rick Crawford modified LS3 intake (installed last November, never dynoed with OEM intake but VE needed 3-8% more fuel at 100kPa with the modified intake#
OEM LS3 heads #milled .020 if I remember correctly#
SRP pistons with 5cc valve reliefs
EPS 222/230 112+2 cam
ARH 1.75" headers through SLP dual/dual #cutout was capped during pulls#
T56 transmission
LS7 clutch w/ 13lb flywheel
Temporarily had to use an OEM steel driveshaft instead of normal OEM aluminum due to bad u-joints
17x11 wheels & rear tires #not the lightest#
10-bolt w/ 3.73 final drive
Dyno WB02 was placed in the tailpipe even though I requested they use one of the dedicated wideband bungs in my collector
Dyno operator refused to let it pull to 7000RPM even though it was barely falling at 6500RPM



I like the wide flat curve but I'm wondering why the AFR is high below 3900RPM and if it's normal for this cam to have that curve after roughly 5500RPM #it doesn't seem to in the C6 graph below#. I'm admittedly a little disappointed when comparing it to a very similar EPS cam on the same type of dyno but it is in a '08 C6 A6:

http://forums.corvetteforum.com/c6-t...o-results.html

I don't drag race so it's not as simple of seeing how the trap speeds compare, but could the differences in the curves be simply due to the platforms & dyno's?

Edit: Added calibration.

RyderTA

iTrader: (3)

Your numbers do seem a little low for a ls3 even with a small cam but what really catches my eye is your afr, that is really lean in the high rpms. Do you have cats?

1989GTA

Me too. Looks to me like your car needs a tune. That AFR is crazy. Makes me wonder what your timing tables look like.

427zm

iTrader: (9)

The cam isn't large for an LS1, so it's real small for an LS3. Your bottom is forged, and I didn't see anything that indicated the heads had been ported. They need to be. Being that you have valve reliefs even w/ a .020 milling, you need more CR IMO. Realistically, though, this cam is going to be a great driver cam in your car. It'll sound great, while adding a little punch over stock. But that's all it is honestly. This cam is only slightly bigger than the stock C6Z cam (211/230). A 227/239 on LSL's would've been a better choice IMO. I'm not sure what your expectations was, but bumping compression, porting your heads and adding cam would take this setup to the next level. With the right compression, good head porting, and more cam, I could see 450+ on a Mistang, near 500 on a Dynojet.

JimMueller

iTrader: (9)

I have cats. The concern is not how the cam compares to larger cams, but how it compares to what appears to be the same EPS 222/230 cam except with the cam being on a slightly different LSA/advance, on a different platform on a different Mustang dyno.

The heads were not ported, I would have liked more milling but the builder was wary of milling too much at the time.

My dyno was the result of a roughly $500 6 hour tuning session (most was part throttle related) at a business that sells HPT/SCT tuning classes in Florida. I'll edit the original post to add the tuning file in use at the time that pull was made.

KCS

iTrader: (20)

Different valve events, different car, on a different dyno, in different states.

Why would you expect them to be the same?

ctd

iTrader: (1)

You go into PE @ 10% throttle opening with a MAP of 85kpa. EQ ratio is 1.177 up to 4400 rpm, stoich is set 14.42254, your commanded is 12.25.

Then for 1 cell of 4800rpm your commanded PE is 12.48

5200rpm & above your commanded is 12.82

JimMueller

iTrader: (9)

I don't expect them to be the same; however, I didn't realize the discrepancy could be so large.

Right, so why would the tuner have said the tune was complete with best combination of fuel and spark when commanded AFR isn't near actual AFR below 3500RPM and above 5500RPM in the 2000-6500 pull? For the moment it seems the WOT tune is incomplete.

JimMueller

iTrader: (9)

Here's an updated graph off of Next Level Performance's Dynojet from yesterday. Since my last post, I spent time trying to clean up the fueling and removed/smoothed area of timing where I received knock.

The Mustang dyno AFR was taken from the driver side tailpipe. I have two O2 bungs in each collector, so my in-car NGK AFX wideband is in the driver side #2 bung. The NLP AFR was taken from the passenger side o2 bung despite me telling and noting on the form that I wanted them to use the driver side bung for consistency, although bank to bank it should not be significantly different.

So although the AFR is now flat, it's rich, and I'm going to replace my AFX sensor this weekend and re-test on the street. When I'm told I should still be seeing 450-460rwhp on a Dynojet even with a small cam, but don't crack 420rwhp, then I'm suspicious. What's a reasonable amount I'd gain by leaning out the AFR?



There was a question earlier I forgot to answer, regarding my goals. Looking at my original e-mail for a cam suggestion, my final comments were:
- "How much would I need to lower my shift point in order to get as close to 400rwtq from 2500-6000? I want to maximize grunt in 2nd gear starting at around 2000, but it could start falling off by say 6000... I don't want it to take a nose dive, but if it can carry for a bit and then fall off gradually that'd be nice."
- "I don't mind that it peaks around 6000, it carries well at least through 6500. If I can get my compression around 11:1, with my headers (which don't appear to be on the car in the link also), and the 13ci increase, it should bump the curve up a bit. Definitely want it to pull above 5500. I understand that what you provided was what I requested in the cam sheet. But then I started seeing LS3 500rwhp dyno's which were strong up top but relatively weak below 3500 and that's not what I want. I take it since the 222/230 cam peaks a tad lower, the torque wil also be a tad higher below 3000? If so, I think the 222/230 is a better fit for my goals. "

The second paragraph above is in response to the information provided below, which set my expectation on the area under the curve for the suggested 222/230 cam, although the graph is no longer available:

"Here's the power curve you can expect with a 222/230 cam and 6.0L. This 223/231 LSL cam example will peak just slightly higher than the 222/230 with EPS lobes in a 6.2L. https://ls1tech.com/forums/dynamomet...p-446rwtq.html. A 218/226 cam would make a little more torque at 2500, but it would not pull above 5500 rpm like this cam or the 222/230 cam. Again, the 226/234 cam recommendation was based on your previous rpm window on your cam build sheet. With every email we exchange, that rpm window gets lower and lower. I thought seeing the curve on a 223/231 cam in a smaller motor might help shed some more light. Again, I find more value in real world results rather than dyno simulations. "

thunderstruck507

iTrader: (18)

looks like something goes wrong at 5500rpm to me...the way the curve starts to drop doesn't look quite natural to me but I'm no expert

Exidous

iTrader: (11)

Ideally you'll want about 12.8 at 4k, 12.5 at peak torque and back to 12.8ish at redline.

Many don't enable PE until after 3k. Your AFR should be about 14.2 (if E10 gas) until 3k&85kPa when PE kicks in.

At most 20hp but I cannot see how rich you are. I'd expect closer to 5-10 assuming you aren't pouring fuel out the tail pipe. Cats are eating a bit of the power too.

JimMueller

iTrader: (9)

Could the PAC 1518 valvesprings have lost pressure on me in 4 years with this cam?

Exidous

iTrader: (11)

It is possible but as I cannot see the dyno graph I'm not too sure. It would like like instability in the power curve above 6000 usually.

Baconz28

Numbers are low in my opinion too. 471rwhp just happened in a LS3 aapplication using Brian tooley Stg 2 cam. Specs are barely bigger than yours but still kinda on the small side. Specs are 225/238 612/585.

BODUKE

Run the car at the track! Dynos are for tuning if the car runs good take it to a drag strip. Thoses are the numbers that really matter

JimMueller

iTrader: (9)

Drag strips aren't my thing, and that's why I didn't want a drag strip cam with all the power in the upper RPMs.

handyandy496

iTrader: (9)

That cam seems all wrong for that engine and what your looking for. Talk to somebody like Martin at tick and check a spring(or scrap em all for cheep insurance)for sure. Sounds and looks like its time for a change.

JimMueller

iTrader: (9)

Playing with the run viewer, look how rough the curves are at the upper RPM's with smoothing set to zero. I remember posting earlier in the tuning forum asking about a bouncing MAP kPa at WOT in the upper RPMs. Does this help narrow the issue down?

https://ls1tech.com/forums/generatio...striction.html

1989GTA

First of all the smoothing is 0. I would put it on 5. When that is done then see how smooth the lines are. Also near as I can tell you still have some work to do on the AFR. That part of the graph needs to be expanded so we can get a better definition of where you are at.

JimMueller

iTrader: (9)

In post #9 I acknowledge there is a discrepancy between the dyno shop WBO2 in the passenger bung and my in-car WBO2 in the driver side bung, and state that I'm replacing the in-car sensor this weekend. Both smoothing options are already posted, with smoothing set to 5 in post #9 and smoothing set to 0 in post #18.

So you're stating that the really rough graph with (smoothing set to 0) in the upper RPM's can be caused solely by being too rich? Here's the biggest AFR graph I can get you.