hey guys need some guidance on this swap. 88 crx hf (orig d15b6 8 valves mpfi) engine shot. replaced block and head with d15b2(16 valves ) used hf manifolds. problem: vaccum leak egr engine idles rough disconnect egr engine runs smooth and no power on highway. the block and head were completely rebuilt. any ideas....please help....thx

 

Switch to an Si (PM6) intake manifold and throttle body, preferably the exhaust manifold too, and use an Si ECU (Si camshaft preferably as well but not necessary). Or you can remove the head and rebuild your original 8 valve head and correct the problem.

The problem is that you are using 8valve HF specific equipment on a 16valve DX engine.

 

Can't see why it wouldn't work.

Are you saying your EGR is leaking vacuum? - if so, you probably have a Check Engine Light while driving as well.
Or is something else leaking vacuum?

 

o/p you shouldn't have a problem, people have swapped in 16v d15s using hf stuff before w no issues, i'd check the egr valve's gasket, and clean the egr valve

 

im getting conflicting info on this swap. some are saying u can use a d15b2 block and head on a 88 crx hf (orig 8 valves) using hf manifolds and ecu with no issues. can someone help with this please.....THX: