440 Heat X-Over Blocked. Runs Different Now

[3yearcuda]

I loosened and lifted slightly my EB RPM intake and slid in some tin flashing pieces to block off the heat cross overs on either side. I put a very thin coat of high heat silicone on prior to sliding them in, but you know how that went........most piled up on the outside of the intake. I re torqued it all down and then went for a rip.
But, now something aint right. Lost some power and seems to flutter a bit. Idles fine but seems a bit soggy now when i punch it, compared to before.
If i lose the get up and go from blocking them off, i would sooner deal with the cooked look around the intake ports.
Is this air being sucked in cause i didnt get a good seal after putting the tin pieces in? or, is this an issue with blocking these crossovers off.
The temp here when i went for the ride is +15c or 59F. Thanks for any help you can provide.

 

[3yearcuda]

Talked to a buddy today that got lucky with a quick lift of the intake and placed his tin pieces to block off the heat crossover. He said his 440 ran better and seemed to have more power.
Needless to say, luck wasnt on my side and now have my hands on some new felpro intake gaskets, so i'll remove the intake/770 holley and do it right this time.
I'll report back to the thread and let all know how things go.

 

[3yearcuda]

Pulled the intake and carb off, cleaned things up and installed two pieces of flashing/thin tin over the holes, new felpro gaskets and buttoned it all back down. It takes awhile to warm up, ie: 5-10 minutes of driving, but runs much cooler, starts better after being shut off and best of all, isnt cooking my shiny Endura clear coat off my intake.