Re: Vortec or not?
Ok - I should have counted better. It is a 12-bolt intake. It seems 1996-1997 were inbetween years.
Yes, that make more sense to me. There wasn't any production Merc with vortec and 4brl. Only 2brl carb, TBI, or MPI.
Anyway, the reason I ask is that I am thinking about replacing the intake manifold this fall. The boat has a new shortblock from previous owner due to not winterizing. It had been used in brackish/saltwater. I only boat in fresh. The exhaust crossover under the carb (I think that is what it is) is really looking corroded.
If it is surface rust on the exterior, that is normal and is caused because of the heat burning the paint off.
The current intake is a high rise style, I am thinking of replacing with Edelbrock performer. I doubt there is much if any performance gain, but I don't want to loose any going from a high rise to a low rise.
That high-rise will perform better than a Performer intake at high- near wot rpms. Performer is more of a mid-rise.
Currently the engine pulls extremely strong, but starts to sign off around 4000rpm. I have a 16" 4-blade and I can get to 4400 rpm. What is odd is that with either a 16" or 19" prop I can easily pull skiers with a full load on the boat. It just does not want to run over 4000rpms.
You may have something wrong with that Weber. First thing I would check is if the primary and secondary butterflies are fully open when the throttle is fully forward (engine off). You can lightly press down on the secondary air door, to see how the butterflies are open. Then I'd check the air door operation at wot rpms on the lake. Need to have an extra observer along for that
That Weber is 750cfm, so don't expect the air door to be fully open.
