MERLIN vs DART HEADS
 

I'm open for suggestions. From what I hear there is more zinc content in dart than merlin. The merlin heads I had were brand new when purchased in '95. Always flushed religiously after every use. At the end of the season 1 engine blew apart due to water entering a cylinder. The cause of this was a rusted water jacket above the exhaust valve. Needless to say what started as a pin hole developed into a water pressure washer and the rest is history. From what I hear the dart's will give you more horsepower out of the box than merlin. I really dont mind spending the money for somthing that may last longer with better results. I have recently heard of some problems that merlin has had with castings. Has anyone had this problem ?

Hmm, I can't tell you which is better, but I can tell you why I purchased the Merlin Marine heads over the Darts.

The Merlin marine heads use non ferrous valve seats, Inconel exhaust valves, Manley severe duty stainless intakes and have the "D" shaped exhaust ports. Sounds like the right parts for a marine engine to me.

Will let you know the outcome in the near future.

As far as performance I had no problems with merlin. The problem I am expirienced is the quality of the product.

Ouch. Did World Products put forth any effort to fix the head, or offer an explanation?

heads
 

i have had darts first and merlins after and the darts flow great numbers out of the box but i had a head that cracked. And dart told me that they do have problems with there heads in marine applications and gave me two sets of dart pro1 heads warranty call dart and ask them for info

asd-6, They would'nt do a thing about it. Once you mention marine use they change thier tune. Salt water use,out of warranty
mtm How long were the heads on the engine before cracking?

i bought the dart iron eagles when they first came out.i bought four heads from summit 2 heads were cracked along the intake surface right out of the box.Sent two back to summit and they sent me two more.I had port work done and found out that one of the head bolts was drilled f up . After redrilling them i finally got them on the motor and they made great power until one of them cracked in less than 100hrs. I will say that dart was more then understanding and sent me 4 new aluminum pro 1s.

mtm, did dart charge you anything for the up-grade?