Old and new tune













Edit... FINALLY posted some pictures... This is the second time ive built this motor. 02 z28 camaro 6 speed with 9" rear with 4.11 gears. The first build I put in scat rods and mauhle -4cc pistons. all arp bolts. tv2 cam, 243 heads, ls7 lifters 7.4 pushrods and ls6 intake. decked the block and milled the heads. Motor had 10.9.1cr. kooks 1 3/4 headers with true dual 3" dumped. With a Pat G tune it made 438/405.

After breaking a valve spring and finding helicoils in my rocker bolt holes (not being able to tourque the bolts down) i replaced all the springs and two helicoils that come out put it back together and after two weeks the bolts popped out... My wife told me to just go ahead and buy the heads i wanted so that is when i found Tony Mamo and his new sportsman heads...

After tony schooled me on a few things I ended up going with the sportsman 223 milled to 56cc with hollow valves and yella terra rockers... few weeks later I told my wife i need a cam to match these heads, so I got tony to spec one out for me... 235/240 615/620 113+3 cam. cosmetic .054 gasket for 11.4cr and also went ahead and ordered some short travel johnson lifters and measured the pushrods for a few different custom sizes... the kicker with all this is i still have my ls6 intake and change my exhaust to 2.5" dual with x pipe all the way back through single chamber mufflers and cme.

So now that it runs and drives (by the way tony it sounds great!) I have contacted Pat G to get another tune in, hopefully to get some better numbers under the curve as well as at the top!

 

Sounds like a fun combo! We need a video to confirm the great sound, though

Any idea when you'll go for the intake/exhaust upgrades?

 

I'm keeping the exhaust like it is or will go to 3 inch. I wanted duals all the way out the back but also wanted to lower the car some so that's why I went with 2.5", the intake will be when I get some bills payed off. Also have my first baby due in about three weeks so that will put a damper on getting a intake. I'll get a video soon, probably this weekend

 

excuse it being dirty still need to wash it!

 

Sounds really good man! What dual setup did you use? I need to convert mine over one of these days.

 

It's just a custom setup. I did a lot of research and screenshot pictures, bought the single chamber mufflers, x pipe, and CME off eBay then brought it to a shop and they did it lol... If I would do it again I'd probably go with speedenginering. I had there headers on my last car and liked them alot I figured the duals would be nice also as well as affordable

 

Well brought it to Pat g. They have updated the dyno since last time I brought it. They told me it read about 5% less than most other dynos. Also the motor was not getting enough air. Results better heads and a bigger cam 432hp/409tq. Lost HP gain a few tq. Guess it's time for a fast intake now

 

Yikes!!!

 

Were the 243 heads worked at all? Or just stock and milled?

 

Yeah but looked horrible.

 

It was just the ends of the runners not the entire runner. Also had valve job

 

So in this case the ugly duckling was worth more than the showpiece.

 

Just wondering, can you feel the ~25 ft-lb difference around 2200 RPM that the graph shows? How does the car feel after the new mods, and do you have any before track times to compare to?

 

Pretty sure more than just the intake is wrong here. I'd be really pissed after blowing that kind of dough and not getting a return on my money.

 

Driving wise from a roll at 2000 rpms 1st gear blew the tires off in 1st 2nd and 3rd with nito 555s the last build from a roll like that would barely spin. I wonder what the fast intake would do on the 243 heads vs the Mamo heads. I would think that the 243 heads were peaked out almost where as the Mamo heads are starving for air.

 

Also the 25' lbs around 2200 are the last tune z camaro

 

Don't get me wrong, a FAST intake will help a lot, but it would have also helped quite a bit with the old setup. I do think you are correct that the current intake is more of a restriction now than it was, but how much I don't know.

 

I am assuming that the old setup is the dark blue and dark red lines since you said with the new setup you lost a few hp but gained a few tq. If so your new setup is down ~25 ft-lbs compared to the old at 2200 RPM yet it now blows the tires off and wouldn't with the old setup? This is kinda contradictory (save for the road and tire conditions). Could just be the dyno then.

Let me know if I am not interpreting the graph correctly.

 

Yes, correct. The old set up had more HP and tq at the 2200rpm... But the old set up was also on their old dyno set up. They said the new computer on the dyno is very stingy and if I would to bring it to Houston it would read 5% more. So if that's true the dynos in Houston would read around 453hp and 429tq

 

The valve job, as most know, will make or break the performance of the heads as a whole. What was the target RWHP goal?