Yes the kit is worth the money, I went 12.6 @ 108 on 26" x 10.5" M&H RACEMASTER D.O.T's with the kit and I had bad heads from Holley.
I went with a bigger more aggresive cam when I got the replacement heads from Holley and everything is in the sig below. I have went a best of 12.16 @ 113.5 on a 1.78 60ft, with more traction it will go 11's and my cam is made for 4:30 gears which will be going in shortly looking for mid 11's.
If your 88 is still Speed Density you will need to convert to Mass Air, they do offer the kit with a less aggresive Emissions legal cam .512/.512, 218/224, 112, the non emissions is .509/.509 218/224, 102/107 with a lot more overlap, very choppy.
As already stated
EXCESSIVE SUCKS *** , STAY AWAY FROM THEM AND THEIR CLAIMS
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Check Out My Site 91GT,Holley SysteMAX II Kit-Heads 2.02" x 1.60" port matched to a 1262,Anderson N-61,24#,76mm C&L,Full MAC, No A/C or PS or emissions, 12" K&N Filter,RNH PERFORMANCE Ram Air,Ron Davis Radiator,Full Suspension, SPEC stage III clutch, Lakewood SFI bell, S&W 8pt "X" brace,JAZ seats,3:73's,Welds..etc,4:30's and 31 splines coming very soon!
[b]12.16 @ 113.5, 1.78 60ft..no traction in the 90 degree