R
rel3rd
Guest
After doing several mods (heads, 1.6's, longtubes, ported intakes, etc...), some will recall that I had very bad luck on the dyno....soon after I found out I had a wiped cam lobe and a semi clogged catalytic converter. 
http://forums.corvetteforum.com/showthread.php?t=1660265
anyway...
Went back today to see if my luck had changed. Car's been running nice with new $60 Summit cam/lifter package. I did have a few CEL issues that I traced to a bad CTS sensor connector. On the 60 mile drive up, I felt that car was "close" to running as good as it probably could. Very smooth, no driveability issues, no idle issues, all was well....
Tuning parameters were as stock....6* base timing, 38psi base fuel pressure.
Fresh off of I-95, I made a 2200-5800rpm pull....
http://home.comcast.net/~rel3rd/wsb/media/373752/site1437.jpg
http://home.comcast.net/~rel3rd/wsb/media/373752/site1438.jpg
As you can see, there is plenty of torque damn near everywhere, and no TPI "cliff" where horsepower dropped off rapidly, as many insist every Long Tube Runner intake will do. I love a broad, flat power curve and this car has it. A backup pull was near identical.
After nothing more than a base ignition timing "bump" up to 12* (something else that many say is a worthless mod), we made another pull (2200-5400 rpms)...This pull wound up being best of the day...and what I ended up with. My a/f ratio was right where I wanted it, hovering around 12.8:1, and stayed pretty constant throughout rpm range.
Again, very nice broad and flat graphs, which makes for a fun street car.
Check out the torque numbers....
http://home.comcast.net/~rel3rd/wsb/media/373752/site1440.jpg
Overall, I cannot complain at all with end results of this combo. I have about $2000 invested in engine mods and I wanted a lower rpm, decent idling combo that didn't "need" a chip to run decently. I honestly cannot see where any chip can improve what I already have, to be honest. Alvin @ pcm4less said that my stock 1985 #870 pcm should stay right on the money as far as a/f ratio, and he was right.
Combo is as follows:
Summit (TFS) 170 heads (2.02/1.60 valves)
Crane 1.6 roller rocker arms
Summit 1102 camshaft (hydraulic flat tappet, .448"/.471" lift w/1.6's)
self ported 3860 Edelbrock base intake
self ported and siamesed SLP runners and plenum
24# Bosch (Ford Racing) injectors
Hedman Elite 1-5/8" longtube headers
2-1/2" front & rear Y pipes, gutted cat
Dynomax Ultra Flo stainless mufflers
Cliff Notes:
275rwhp/356rwtq, bumped up timing 6* and got 287rwhp/374rwtq
http://forums.corvetteforum.com/showthread.php?t=1660265
anyway...
Went back today to see if my luck had changed. Car's been running nice with new $60 Summit cam/lifter package. I did have a few CEL issues that I traced to a bad CTS sensor connector. On the 60 mile drive up, I felt that car was "close" to running as good as it probably could. Very smooth, no driveability issues, no idle issues, all was well....
Tuning parameters were as stock....6* base timing, 38psi base fuel pressure.
Fresh off of I-95, I made a 2200-5800rpm pull....
http://home.comcast.net/~rel3rd/wsb/media/373752/site1437.jpg
http://home.comcast.net/~rel3rd/wsb/media/373752/site1438.jpg
As you can see, there is plenty of torque damn near everywhere, and no TPI "cliff" where horsepower dropped off rapidly, as many insist every Long Tube Runner intake will do. I love a broad, flat power curve and this car has it. A backup pull was near identical.
After nothing more than a base ignition timing "bump" up to 12* (something else that many say is a worthless mod), we made another pull (2200-5400 rpms)...This pull wound up being best of the day...and what I ended up with. My a/f ratio was right where I wanted it, hovering around 12.8:1, and stayed pretty constant throughout rpm range.
Again, very nice broad and flat graphs, which makes for a fun street car.
Check out the torque numbers....
http://home.comcast.net/~rel3rd/wsb/media/373752/site1440.jpg
Overall, I cannot complain at all with end results of this combo. I have about $2000 invested in engine mods and I wanted a lower rpm, decent idling combo that didn't "need" a chip to run decently. I honestly cannot see where any chip can improve what I already have, to be honest. Alvin @ pcm4less said that my stock 1985 #870 pcm should stay right on the money as far as a/f ratio, and he was right.
Combo is as follows:
Summit (TFS) 170 heads (2.02/1.60 valves)
Crane 1.6 roller rocker arms
Summit 1102 camshaft (hydraulic flat tappet, .448"/.471" lift w/1.6's)
self ported 3860 Edelbrock base intake
self ported and siamesed SLP runners and plenum
24# Bosch (Ford Racing) injectors
Hedman Elite 1-5/8" longtube headers
2-1/2" front & rear Y pipes, gutted cat
Dynomax Ultra Flo stainless mufflers
Cliff Notes:
275rwhp/356rwtq, bumped up timing 6* and got 287rwhp/374rwtq
Thanks for kind words. I already have underdrive crank pulley though. FWIW, this is the third Chevrolet car that I have owned (over a time frame of 15 years), that "wiped" a flat tappet cam for no apparent reason...
