Hi guys,

After a 1 year break I am back to work on my '68 Firebird TBI conversion for the Pontiac 350 (which may become a 400 or 455 one day). I have a complete system from a '95 C-1500 4.3 but I need (I think from my research) a 7.4 TB unit. I have punched the numbers into the excel spread sheet and for 300HP it shows I should be using the 7.4 and I think the flow is 670 cfm for the 7.4 TBI which I think is close to the small QuadraJet.

I have a couple of 305/350 TBs and have found a 7.4 from an '87 and the base from a '92, missing the injector pod/regulator plate.

So my question is, what can I mix and match between the 350 and 7.4 TBI units? Is the IAC the same? TPS? ( I know over the years the plug changed) Fuel regulator spring? How about the injector/regulator holder, same?

Some of the units I am finding are quite a drive and I want to make sure before I commit that I can make them work. I know I will need the 7.4 injectors and will probably buy new.

So, any help will be greatly appreciated.

Thank you.