Yeah-I was speaking to a member at a local cruise night and he had said you can use the F-body mass airflow which is 3 1/2 in's.The B-body uses a 3in-I'm not sure about the 52mm on a stock engine though.Someone else will chime in.That's a great price.Ed
Under 300RWHP, likely no gain at all... past 300 you're approaching the limits of the 3" MAF to accurately measure air, hence time to go to the larger F-body one, which should be sufficient for just about any NA LT1 out there.
I agree, however.....I have noticed better throttle response with the larger MAF. Now I did not descreen the stock B-Body unit so perhaps it would have been the same, but I can tell you first hand the SOP feeling was simply that the larger MAF was a better response.
After the Herter program, it was even better and the cat-back didn't hurt either!
I have no personal experience with the Granatelli but I have read and been told by persons using them that there was little or no HP increase with them over the 3.5 inch on a moderate engine. They are also not supplied with MAF tables and are inconsistent in that respect.
The nice thing about the "F" is it is a known quantity and you just need to plug in the "F" car tables and you are set.
Since your are a PCMFORLESS customer, the "F" MAF is as simple as "hey Brian I changed to a "F" body MAF"
I know at least one person who traced drivability troubles to a Granatelli MAF, as stated above the calibrations for it are unknown, the stock F-body tables are known. Im my sig it says ZO6 MAF and wish I had just gone with the f-body piece. It is about the same size but will read less flow in this application(due to pcm differences), but is available new for less money than a new f-body MAF.