bandit0220

Carlos I may just be interested I wouldnt have to wait for my set to be ported and I have a guy interested in buying mine hummmm send me some pics we may to work something out

bandit0220

Also herbert what kind of cam would you change too if I can attain a 75% intake exhaust flow ratio?????

6Speeder

I agree that going too big will cost velocity and low end and throttle response will suffer. It appears these ports aren't too big as my throttle response is better with the ported heads than it was before. Also, as I didn't change the cam (which I presume,was designed to compensate for the stock exhaust flow rates) then, porting the intake and exhaust seemed like a better answer than just the exhaust.

Steck and Bandit, I'd sure like to see your dyno sheets, so we can compare exhaust only, compression only, or my full porting and compression.

I'll show you mine......:o

DSteck

The only thing I can show is from cam-only because I had scanned it. I don't think anybody here cares about cam only, though. I don't know where my other print outs are. :-/ If I head back to the dyno soon, I'll bring a print out and try to take a picture with my camera. Now that ktoonez released that version 3 of EQ VE with all the HPT hooks, I have an excuse to go back and tune the VE.

I don't know how worth while of a comparison it'd be though. We have 93 octane here, and I think we all have different cams.

bandit0220

I dont know how to post pics but will try mine wont compare well because mine is uncorrected and I live in Utah 4500 ft above sea level so if anyone can figure the correction factor on 548 rwhp and 502 rwtq then Id love to know what it makes at sea level.

We all have different cams, different octane, and different altitudes

Me, I have a custom cam 243/257 657/630 110+4.........91 octane.........4500 ft above sea level
Steck, has a QM600 I cant release the specs but similar to mine but trust me when I say two very different animals I tested over 12 cams so far............93 octane.........altitude????
6Speeder, I dont know what cam your using..........???octane............alti tude????

J HEBERT

Bandit, sounds like u are running a version of my old cam, a healthy beast too.
exhaust duration never hurts when u are spraying, but for all out N/A #s there comes a point where the extra duration on the exhaust stops yeilding more power at any point on the rpm scale. In turn, u can run less overlap, get on the powerband quicker, and ohh yeah, did I mention less overlap??
I realize that some of us are hardcore, but I see too many people chasing a peak hp number, and that is not what makes a happy street car, let alone a fast one. When u start to overlay dyno graphs of different cams (DO NOT IGNORE 3k rpm #s!) u begin to see. 547rwhp can indeed spank the 600rwhp car. Set-up is everything and it must all work in harmony, anything else is too much compromise.

On another note, who wants to go to the track tommorow night?
Give me a jingle.........

6Speeder

I'm running the QM600 also, 91 octane, 5500 ft. Although my house is at 6000' and we frequently race at DA's in the 7-8000' range.
Dynojet has free software that allows you to down load the run from the dyno computer, manipulate it, change to sae, std, ect. Yu should get the dyno operator to send you your file and play with it.

You can go here:
http://www.wallaceracing.com/braking-hp.php

to get corrections, but really, correcting for Density altitude is more relevant than actual altitude, and you can get that by getting your file of the run and changing the results to SAE.

BTW: Correcting for actual altitude gives you 622 rwhp/570 rwtq. Studly numbers indeed. That being said I would suspect the air was probably better than 4500 feet for your run. But who knows.

ramairws6

I'm ready to bite on this little comparison game. My combo is slightly different since it is a 441 but my cam specs are quite similar to Bandits. I do have both the exhaust side and intake side ported as well as the intake. I started out with just the exhaust side from WCCH since nobody else was doing the intake side at the time and that was on my 427 last year with the QM600 cam. I did like that cam alot and I really think it pulls similar to my stick now. I'll dig for my dyno sheets and post them to see what everyone thinks. Now remember, I have a Trans Am with a 4L60E and a Ford 9 inch...........so no bashing on my RWHP #'s. Traver

bandit0220

Traver your car is badass and after watching your run your rwhp numbers dont do the car justice as I know you are doing it through a very heavy and hardcore drivetrain like me. As to the 622 rwhp and 570 rwtq i dont think it was near that maybe just cresting 600 rwhp or so. But I do love the way the car pulls. Like I said i gained dam near 30 rwhp just from the compression and seeing as I can have the intake just cleaned up not much just a little hand finishing by the guys at chapman and then have the exhaust opened up to around 265 or so maybe more which will give me a good I/E ratio and then change the cam to one that would compliment the new head flow I will see what it can do ...............or Ill just leave it as its already able to blow the tires away at 70 mph hahahaha

ramairws6

Ya, if I remember that long ago my exhaust side cleaned up to about 249 at .650 and my intake side is 389 at .650. I wish I could have had more time to play with this thing before I got the boot! Numbers don't mean as much as track times and me weighing in at 3820 and running consistant 10.3-10.5's NA..................well I'm as happy as could be!!

ramairws6

http://s257.photobucket.com/albums/h...Picture041.flv http://s27.photobucket.com/albums/c1...t=Traver64.flv

6Speeder

Here's stock, with bolt-ons, and then bolt-ons and cam.


I'll post with heads when we get her on the dyno and tweak the tune.

DSteck

Kick your tuner for not knowing how to fix the hard torque dip in the 4000rpm area.

Here's my cam only, just to see how your's compares. I'll try to hit the dyno, but things are going to be really hectic until after new year's. Also, I realize the irony in my torque dip comment above, yet mine from cam only did the same thing. I didn't figure it out until after the dyno session. I also only got to make two pulls that night because we ran out of time (I was granted a favor in using it, and the previous car took longer than expected). This was with only 24º peak timing and about a 12.0 AFR (as mentioned, didn't have time to finalize it).

6Speeder

Well, our curves look pretty close, as they should, running the same cam. What did you do to eliminate the sag in torque? I'm thinking it's the GM VE algorythm, I'm gonna go straight MAF only.

bandit0220

Sorry I really dont like the torque curve of that cam it is exactly like I said in my review of it, its torque curve is very short where my cam has over 400 rwtq from 2700 rpms and it dont go below that till 7050 rpms and from 4k too 5300 its over 500 and dont go below 450 rwtq till after 6650rpms. An my cam dont just suddenly take off at 4000 rpms like the QM600, mines pulling a nice steep upward sweep throughout.

0Myhardtop

Spoken like a guy who has been around the block a few times.

Jherbert is right! Air Velocity is what you want

Thanks,
Carlos

0Myhardtop

Please PM me your offline email for some pics.

Thanks,
Carlos

PS, I had three PM's these past two days regarding the heads, one from Jersey and two from Texas...let's see what happens

0Myhardtop

Yes and no. Remember, the QM600 was designed to work like the stock curve but just with a little more flare on the low end and big salsa on top. Sure you can a have cam come on sooner but for most people, having to feather the throttle due to too much down low takes the fun away when meeting with Mr. 911 TT or Mr. AMG SL65 on the next lane. Risking the chance of excessive wheel spin is no fun and remember, from a dig a stock Z with stock or similar tires are already a hand full to deal with.

We have cams that will sufice the need for those who prefer earlier RPM grunt. A while back we realized that the QM600 was the best compromise. I mean, if you look at it, it is an improvement over stock in every way...it all depends on what you want from a cam swap.

You can always get gears with your QM600 and enjoy the best of ALL world and really wake that Z06 beast In case some of you didn't know, 390 gears on a Z06 is like adding a 50 to 60HP shot of NOS...I mean it! Couple all this with your QM600, Heads and then a little juice (75 to 100) AND I tell ya, even large CC modified bikes will have a very tough time catching you.

Don't get me wrong homie, I like bottoms...oh wait, that's another topic

Thanks,
Carlos

bandit0220

ewwwwwwww carlos likes bottoms as long as you keep that to yourself LOL

DSteck

Bingo. Under 4000rpm, there is a lot of bias towards the GMVE values which makes the engine lean out. Running MAF only or tuning the GMVE coefficients solves this.

My torque curve looks goofy because I still had a totally untuned set of GMVE coefficients active.