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Discussion Starter #1 (Edited)
I made it back from 21st Century Muscle Cars thankfully safe and in one piece.

Following are my initial impressions after nearly 1500 miles of break-in and some pictures. The mileage comes from driving 500miles in and around Dallas and N. Dallas, the 700 mile road trip home and another ~150 miles around Omaha.

Impressions

21st Century Muscle Cars is a AAA class operation and here's another big thank you to John, Andy, Patrick and Jonathan for the excellent work and kindness. My heads and cam package includes:
LPE heads, GT12 with 112lsa (not sure if I can publish the specs), underdrive pulley, LPE throttle body, LPE oil pump, Hurricane CAI, Halltech air bridge, 30lb SVO injectors, Beru plugs, Magnecor wires, radiator screen, Elite Engineering tunnel plate, LPE hardened output shaft, Textralia OZ700 clutch, Baer eradispeeds, Motorsport wheels, LPE fuel rail cover and floor mats, and finally poly sway bar bushings. In 125 degree heat and with 91 octane in the tank (no other additives) the car made an unprecedented 450 rwhp and 390 rwtq.

I'll post a sound clip in a later post but I think it can best be described as deep, mellow but lopy; especially after the pcm goes in closed loop. You definitely feel and see the shake, I like it - a lot. Inside the car, the exhaust tone seems smoother and "quieter" than before. I can't explain why, but it is what it is. Outside the car it sounds sweet especially under WOT. Not harsh at all. Acceleration is smooth, although you definitely can tell where in the curve the cam comes on. It really begins to pull from 3000rpm. The car cruises well at 13-1500 rpm in all gears; but "lugging" is felt below 1300rpm unless under acceleration.

As for acceleration, my perception is that the car pulled harder before the changes from off-idle or from cruise until about 3000. I attribute this to the steel flywheel vs aluminum and the heavier Motorsport wheels. Those two things and the cam have made getting used to starts from a stop especially tricky. The clutch itself is great and the pedal feel is just like stock. I'll try my OEM wheels before I make my final judgment but at my torque level it may not have been the best choice given the heavier flywheel. (Update on edit: My perception above was colored by the effect of extreme air temps and engine heat soak during that period 95-100 degrees. Now that I have driven it up where the average air temps were mid 80's -peak- the car accelerates very hard and noticeably harder than before - in all gears. The clutch operation is fine. As for the Motorsport wheels, all I can say if the car pulls like this with them then it will be scary with stock weight wheels. )
The most noticeable improvement other than the power was the addition of the tunnel plate and poly bushings. The car has a significantly more solid feel to it than before. All aspects of cornering have become more controlled with the new bushings though there is a small compromise - I can sometimes hear them squeak. The combination of baer eradispeeds and Z06 pads is awesome albeit with increased dust. I was using the ceramics but the trade-off in increased stopping power is worth the extra dust.

I did have to get used to the car (cam and new clutch) and I think I now have it handled. In cool temps the car is scary fast but controllable and I though I love the top end; I would prefer more low end grunt.

Pictures:




















Special shout out to Rick, and Richie sorry we couldn't meet - I left something for you at 21CMC.

-RR
 

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Very nice. Have fun with the roll-ons. Cool floormats, too.
 

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roushraven said:
Here's the dyno sheet:

Dyno sheet.jpg

-RR
Did they explain why their is such a large drop in the torque output?

I thought '03s came with about 360 rwtq stock??
Thats approx. 30 ft/lb diff. ???

seems a bit low...
 

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OhOneZOhSiXXX said:
Did they explain why their is such a large drop in the torque output?

I thought '03s came with about 360 rwtq stock??
Thats approx. 30 ft/lb diff. ???

seems a bit low...
This power curve is indicitive of a H/C power.

H/C will give you a sizable jump in HP, but marginal jump in torque. Remember, torque comes from cubes.

All H/C kit does is increase the air flow in and out of the engine.

If you want a sizable jump in torque, got to go cubes or F/I.
 

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Discussion Starter #8
tlaselva said:
This power curve is indicitive of a H/C power.

H/C will give you a sizable jump in HP, but marginal jump in torque. Remember, torque comes from cubes.

All H/C kit does is increase the air flow in and out of the engine.

If you want a sizable jump in torque, got to go cubes or F/I.
What he said plus the car was dyno'd in 125 degree air temp. I'll gain 10-15 torque and hp in cooler temps.

-RR
 

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roushraven said:
What he said plus the car was dyno'd in 125 degree air temp. I'll gain 10-15 torque and hp in cooler temps.

-RR
Did your new cam have a lot of exhaust duration or lift or both compared to the intake? How would you judge the idle quality? Somewhat rough or smooth or what?

D.J.
 

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Discussion Starter #10
OneQuickCoupe said:
Did your new cam have a lot of exhaust duration or lift or both compared to the intake?
Define a lot.


OneQuickCoupe said:
How would you judge the idle quality? Somewhat rough or smooth or what?
D.J.
That's very subjective but for me the idle is perfect. It is set at 900 rpm and it is not at all effected by the aircon. No problems with either cold or hot starts. I wouldn't call it rough but it does have a very obvious lope especially after the engine goes into closed loop.

-RR
 

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Congrats! I am sure you will love the car and those guys do first rate work!


Chris
 

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Discussion Starter #14 (Edited)

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OneQuickCoupe said:
Did your new cam have a lot of exhaust duration or lift or both compared to the intake? How would you judge the idle quality? Somewhat rough or smooth or what?

D.J.
By a lot of exhaust duration I mean 8 degrees or more duration on the exhaust side @.050" lift than the intake. In other words 224 on the intake and say 232 or so on the exhaust at .050" lift. More lift of the exhaust would be say .589 on the intake and say .602 on the exhaust.

D.J.
 

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Niiiice neighbor :zboobie:
Glad to hear you like your setup so much; sweet looking and sounding ride. I'm on the edge of doing something very similar myself. I'm not to far from Dallas and have been considering 21CMC and LGM. What made your decision on tuners. If you had to do it again, would you do anything different. Thanks a ton for sharing.
Drew :cheers:
 

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Discussion Starter #17
amriche said:
Niiiice neighbor :zboobie:
Glad to hear you like your setup so much; sweet looking and sounding ride. I'm on the edge of doing something very similar myself. I'm not to far from Dallas and have been considering 21CMC and LGM. What made your decision on tuners. If you had to do it again, would you do anything different. Thanks a ton for sharing.
Drew :cheers:

In selecting 21st Century Muscle Cars to be my tuner, it all came down to my satisfactory previous experience with them, their timely response to my calls and e-mails, their willingness to answer my many questions regarding package options, and their community wide solid reputation for reliable work.

I was on the fence for a long time concerning this upgrade project. I searched the forums and gathered lots of opinions but in the end when I was ready to pull the trigger John Page was the only one to spend time with me.

The only thing I would do different is stick to my original plan to install 3.90's and add the MCM hood - that thing looks awesome in person. Once I get used to this new power I would have no reservation going back for the next step i.e. forced induction.

Hope that helps,

-RR
 

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thats pretty good for that cam spec. I made 455/405 SAE with a little lower lift (.574/.578), but more duration (232/236) and a 114LS. CNC LS6 heads by Pete in Florida for RPM.

Have fun with it! :mug:
 

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Discussion Starter #19
OneQuickCoupe said:
By a lot of exhaust duration I mean 8 degrees or more duration on the exhaust side @.050" lift than the intake. In other words 224 on the intake and say 232 or so on the exhaust at .050" lift. More lift of the exhaust would be say .589 on the intake and say .602 on the exhaust.

D.J.
Here are the cam specs 228/228 588/588 112 lsa. Does that help?

-RR
 
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