Really? Cracking intake manifolds? That's crazy. Sorry to second guess you Clifford!

 

pressurize it with air.

 

There's a night and day difference between the Greddy and the Top Speed manifold. The exterior casting is identical (besides where the Greddy logo goes), but what makes the difference is the internal portion of the manifold. If you have both sitting side by side, you will see the and feel the difference between the two. The Greddy is smoother compared to the rough surface of the Top Speed.

As for cracking, I personally have not heard any of them doing so. I personally have always gone with the Greddy manifold and have compared both.

From threads and posts in the past, the Greddy manifold will only really make power on high horse power motors at higher RPM (please correct me if I am wrong); therefore, it would be interesting to see what the differences would be on the two manifolds on a dyno run test.

 

To add, I personally think, it's almost impossible to crack a cast manifold. There are 'seams' that would cause cracking. Only thing that comes to mind would be maybe a warped flange giving a bad seal, causing leaks.

 

ill have to search and see where i read that.
i know i have though. no personal experience though.

 

the only way you will crack one of these is if for example you happen to be running some ungoddly amount of boost and oh say a heavy methynol injection kit combined with hitting the rev limiter and getting a freak back fire ingniting the meth and turning the intake manifold into a cumbustion chamber......not that I have seen anything like this happen

Anyways, yes the insides are different. On my miata I sand blasted the inside to make it better and now its pretty damn good. Even as it is normally its still a big power booster on big turbo cars.

I have never heard of a problem with #3 going lean. The real problem was holes in the casting causing vacum leaks. I have only come across one with this problem. Every one I have received in the last while has been fine

 

WOW, NO WAY!!!! Wonder if that has ever happened....