On a 68-428, P.I. did they come with a carb. Spacer ? & also, if they did, what size would it be.---Thanks,---S.
The simple answer is yes but of course with some exceptions. Most used the .28 thick bakeolite spacer but there was also a short period of time that cars were equipped with the Autolite 4100 (somewhere up to 70-80 cars mid Dec-Jan) that did not receive any spacer. I've also had some cars that appeared to have the original manifold studs and they were too short to use the .28 spacer but I cant say for sure what they had as they were messed with. If I had to make an educated guess I would say they used the .125 stainless spacer like the 390's used.
Really? The largest 4100 (except for a one year only 650 item around 1960) was just shy of 600 cfm, barely big enough for the 289HP. I have to think the 428 would be like a fire truck sucking through a straw with that.
The PI is actually overcarbureted with the 735 Holley. I just restored one of the 4100 PIs and it ran better than any of the Holley equipped ones I ever did.
