This top graph is with an MTI X1 cam and stock LS6 intake, the rest of the mods are in my signature. Red graph, ignore the blue one.



Now since that graph I swapped the X1 cam for an FTI Street Sweeper HT and swapped the LS6 intake for a ported FAST 78.



Here's a chart showing gain/loss:

[IMG][/IMG]

 

Pretty much gained everywhere. The comparison chart is a nice touch. Mid-range gains are nice. Seat of the pants is probably noticable. I'm a little surprised that the forward split cam with the higher flowing intake did not widen the gap further at higher rpm. Guess it goes to show you that the venerable X1 cam is still a strong performer.

 

Yeah it does pull harder in the midrange for sure. Honestly the gains I got I would have expected just by swapping to the FAST intake. I'm not sure I gained anything at all with the cam swap?

 

Im actually really surprised. Is the fast ported? I remember tony mamo saying bang for buck the ported fast 78 was the best bet there was. Seems like a strong setup! What are the specs on the two cams? Im really surprised you didnt pick up more, but again good numbers!

 

I ported the FAST myself, mainly removed the large ridges that stuck out indo the runners and cleaned up the casting marks and then port matched it to the heads.

X1 was 230/228 .592/.571 112+2

FTI cam is 228/232 .598/.598 111+2

I expected more of a gain too, but it does pull hard. I'm doing an RPS clutch that drops 24lbs of rotational weight and I'll probably do an underdrive pulley later too.

 

I believe Viper ported it himself and ported matched them to his heads, if I followed his thread on CF correctly

 

Have to ask - why a 78mm instead of a 90mm?

 

if those cam specs are correct i wouldn't expect any gain going with a cam with 2* less duration on the intake side. maybe a small gain in torque but little if any top end. something like a 232/236 or whatever the xfi lobes are in that range on a 112+2 or so would have picked up imo but all that matters is you are happy. i'm sure that light car pulls pretty hard with 430.

 

Hard to say but the gains are from the FAST more than likely.There is barely a Cam difference to even warrent the change.

 

I got the 78 for $400 brand new on Ebay and sold my LS6 for $300. Ported it myself and was only out $100 out of pocket. Tony Mamo says the 78 only gives up 5rwhp to the 90/92 up top. When funding allows I can swap just the top shell and bolt on an LS2 tb.

 

why the cam swap...seems like alot of work for basically the same cam...did u get the cam for free...

the results you got are about what i would expect...nice gain for $100 unless u had to pay 450 for a tune

 

Nice numbers!

Is the cam the only real difference between the '01 and '02 Z's?

 

It would probably be handy if the tuner had told me what the a/f and timing was, he didn't seem to interested in giving a damn about me even being there, sadly enough.

 

vengeance tune it again?

 

Nice pick up from a ported 78 mm fast. I too have to agree with the questioning "why did you even bother swapping cams ??" Seems like if you were adding 2 or more degrees of lift and upping the lift a bit more then you did it might have helped you make more power. All you did is reduce intake duration and increase lift slightly, while adding exhaust lift and duration. Seems like she exhales better but the inhale is a push considering you have less duration but more lift. Should've went with more duration on the intake side and picked up another 15 rwhp. Who am I though ?? No expert thats for sure. Nice gain from the intake.

 

The reverse split cam I had was designed for stock heads and stock intake, with the ported heads and FAST I thought going to a traditional split would benefit me more in the upper RPM range, but as you can see I didn't gain a great deal.

I didn't want to go bigger on the cam because it's a street car with the rare trip to the track, I wanted a broad power curve that pulls hard from 3,000-6,800 unlike some of these large cams I see that don't start pulling till 4,500.

 

i was thinking you would have gained a little more than that..it would be nice to know your timing and A/F..thanks for posting up the results..

 

yes, it would be nice to know

 

i just read your post on Harcore..yeah,get that tune looked at..sorry you were treated like that..

 

viper, i think u should have kept the X1 and put the ported fast setup and seen what kind of gains u had. i plan on adding LS6 heads or 5.3 heads and fast 92/92 combo with my X1 and see what i get. just look at jaSSon's combo.. its a simple setup TEA 5.3/FAST 90/90/ X1 = 10.6 all motor!!