USING 4TH GEN ENGINE AND EGR INTO 3RD GEN

Did you use the 3rd or 4th generation exhaust manifold?

If you used the 3rd gen manifold, you should review the previous threads here where people have tried that. The trouble is, the 3rd gen manifold delivers the exhaust at a higher pressure than the larger 4th gen EGR components expect (they are larger to flow the right amount of EGR with the lower-pressure exhaust tap on the 4th gen).

You can try to improvise some kind of restriction to avoid getting too much EGR flow, but so far I don't think I've yet seen anyone report getting the engine to run well that way.