I was reading the reviews on summit, and most people said that a lot grinding is needed, also if the piece becomes loose, it might become noisy, so a litlle tack welding should be considered
https://www.summitracing.com/nv/parts/e ... -edelbrock
David Sept 2015
They quality is there however if you plan on using them on a small block you better have the grinder ready. It does say they are for big blocks in the application guide so I can't really give a bad review here. I had to remove almost a third of the material to get it to fit but it's the only game in town for crossover block offs but if your an olds guy like me your used to slim pickins.
Blake Apr 2018
I installed these on a used aluminum 460 edelbrock performer intake that I had acquired used. Upon further inspection I noticed a hairline crack in the crossover. It was suggested to me that I plug the crossover as I live in a warmer climate and don't necessarily need it's benefits. The plugs were considerably larger than the crossover. But I knew that would be the case walking into this. About 45 min to shape the first one... and about 25 min on the second once my confidence was there. Used an electric angle grinder and pneumatic die grinder, sharpie, and calipers... and patience. They do what they are suppose to do. Just be ready to do some shaping on your end.
Nolan Apr 2018
They are better than nothing, Have to grind a lot off to fit olds 455 heads. If the come loose it will sound like knock. I would recommend welding or even tacking them in place with some nickle welding rod.