Cliff,it's is 415ci. ;9.5 to 1 static & around DCR 7.7 to 1 with the Crane #119691 .548/.558 lift w 1.5 ratio rockers(mine are 1.6 Int. & exh.,so .585/.595 lift ;234/242 dur maybe add 2-3 degrees with 1.6 according to Crane;advertised 296/304 dur &76 0verlap;with a normal sbc ci. (2800min.-6800 max. 7200 valve float). The heads are AFR 195 Eliminators(street pkg. with 2.05 Int,/ 1.6 exh.) they flow 280 Int./218 @.550 lift (@ 28" h2o) with 1"3/4 exh. & 4.00 bore my bore (4.125 bore & dynatech coated stepped 1"3/4 to 1."7/8 headers).The exhaust concerns me but the guy out of Kansas has 5 chevelles & swears with 2"1/2 mandrel bend exhaust it will flow as good a 3" regular bent system & without being noisey,so you can carry on a conversation or drive the wife out of the loud car. As far as the intake,I went to a head port guy & he say all the dual planes past 6000-6500 won't hang.(your's does) I was going to buy an Edel.Performer Air Gap but the older Holley Contender port volume is supposedly bigger,even an Afr guy told me that. I added the q-jet open adaptor to increase the plenum size.It may not work.The Holley intake has a divider all the way to the top,so with the open adaptor,I guess the plenum is bigger & kinda like the Edel. air gap. A lot people say the bigger motor's a intake "hogg,try to use a single plane.(you have a big motor & no single plane). A single plane intake may work better but it's a Ac car & the dual planes have the oem tapped intake/ac bracket. Lingenfelter was high on the Holley Contender(just off idle to 7200rpm)sounds like bs,pretty broad. I guess I need to have a Edel. Performer rpm air gap flowed compared to this Holley Contender/Street dominator,same part #. I have an extra Holley Intake that I could flow & compare to Edelbrock to see who's Bsing. In the old days ,I used a 2" spacer on the Holley Strip Dominator,but I had a 5500 stall & .700 lift & lauched higher. A little playing with & tuning. Do you see the q-jet adaptor could pose a problem.Later kelley