[79rustbucket79]

First, the particulars
SBC, 4.156x3.760 (408), light rotating components, 11.65:1 compression, Comp 259/266 tight lash solid FT cam, .586/.608 lift w/1.6 rockers, Ported Iron Bowtie heads, flowing from .100 to .600 lift, 1n/ex:
95/79
148/125
200/174
243/211
255/226
262/226 CFM @ 28" water, flow stalled but not reducing above .600, only one intake and one exhaust port flowed so the other 14 ports ???
Edelbrock Vic Jr, port matched (any easy power gained with plenum porting, possibly step up to a Super Vic?) 1 inch open, 1 inch 4 hole, 850 Holley D/P, Hooker 1 3/4 super comp headers, 3 inch exhaust w/2 1/2 H pipe, 3 chamber flowmasters, no tails, crank scraper, windage tray, 5 qts oil in 7 qt pan, 8 inch 5500 stall (can be reworked to match new cam), TH350 trans (footbrake), 4.10 gears (will be going to 4.56's later on) 9x29.5 MT slick.
The car is a 79 Camaro weighing about 3650 with me and ballast in the trunk (would like to lose the ballast) and it runs in the 11.3xx range at 117 to 118.5 MPH with 60' times in the 1.55 to 1.6 range depending on track condition. Shift points are currently 6800 1-2 and 6600 for 2-3, trap RPM is 6300.
The plan is to have the heads angle milled, shooting for a final compression ratio close to 13:1 (race gas only, no nitrous) and I would like to step up to a larger flat tappet cam that will soften the launch a bit for traction and pick up the power in the 6000 to 6800 range for MPH and ET gains.

Any questions or suggestions?

Thanks,

Doug

 

[Jay Allen]

11.65:1 compression, Comp 259/266 tight lash solid FT cam, .586/.608 lift w/1.6 rockers, 8 inch 5500 stall (can be reworked to match new cam), Shift points are currently 6800 1-2 and 6600 for 2-3, trap RPM is 6300

Do you know what the IC/EC are?
Have you ever checked the cranking compression?
Have you ever checked the flash speed of the convertor?
What is the valve lash COLD?
What does it go to HOT?
Do you know the specs on the valve springs?

Right off of the bat it appears to me that there is a miss match in convertor vs gearing vs cross RPM.

See if you have that other information. I would like to know that before I shoot something stupid out.

 

[94guy]

jay can you take a look at the topic a little further down about "what size header would you recommend". i posted some cam stuff i would like you to look at.

 

[79rustbucket79]

11.65:1 compression, Comp 259/266 tight lash solid FT cam, .586/.608 lift w/1.6 rockers, 8 inch 5500 stall (can be reworked to match new cam), Shift points are currently 6800 1-2 and 6600 for 2-3, trap RPM is 6300

Do you know what the IC/EC are?

-->Valve timing @ .020" Int open 38 close 70, ex open 74 close 42


Have you ever checked the cranking compression?

-->Not recently, but last recollection was 225 PSI, I can recheck if that would help


Have you ever checked the flash speed of the convertor?

-->Flash stall is 5500 according to my playback tach

What is the valve lash COLD? .020/.022

What does it go to HOT? .018/.020

Do you know the specs on the valve springs?

-->Springs are 987-16 Comp, 135 # seated, 325 # open, give or take a bit. They are rated at 344#/inch

Right off of the bat it appears to me that there is a miss match in convertor vs gearing vs cross RPM.

See if you have that other information. I would like to know that before I shoot something stupid out.

Before seasons start next year, converter will be "tightened up" by roughly 500 RPM, and rear gears will be changed from 4.10 to 4.56 in order to get the car off the line better and get the RPM to 6800 or so through the traps. If I put the trans in 3rd (full manual) and cram on the brakes I can get the converter to hit 5800 within a second.

 

[79rustbucket79]

Jay?