Hi,
Ive been a lurker around this board for a very long time. I am needing some feedback from some Salty Dogs on my latest project - the "Frankenrude 100" I am a collector of vintage fiberglass boats from the 1950s. I know my way around OMC 4V engines very well but have a couple questions that I need any insight possible.
The latest project involves putting together a motor that I have wanted to build for years. I am putting a 1968 Evinrude Starflite 100S inside the bonnet of a 1958 Starflite 1. I have done research for years on this and have all the parts to maske it happen. It isn't all that tough, you just need to know what parts you need - model - year etc.
The reason for this is to retain the vintage look of the '58 while having the power and economy of the 100S. Trust me, the 100S gets great economy compared to any of the 2 barrel V4s before 1969. Some call me crazy - some others want me to build them one for their old boats.
OK, so here is the questions:
I want to boost the compression on the 100S (they were pretty low from day 1). The heads from the 1969-1971 90C.I motors bolt right up, and the combustion chambers are better (smaller) I also want to mill these down around .060". I was wanting a cranking pressure of around 125-130lbs. I don't want to detonate the charge & blow out the pistons, so I'm wondering if anyone here has some ideas on what pressures the crossflows can tolerate without melting the slugs. Can someone help?
Also, the problem with carbon causing ring - jacking: I know the crossflows need to hit around 5grand+ at WOT to help recude carbon build up. That and good low ash TWC @ 50-1. However - even with those steps, i still see carbopn build-up on the top ring after just 10 hr. of operation. Any ideas here?
And lastly - yes I realize that this is all old junk. However it is my hobby, I have tons of NOS parts to build & keep it running. Plus I like the looks for my vintage boats. That's why I do it - its fun. Can anybody help with my questions?
Thanks,
Bruck
Ive been a lurker around this board for a very long time. I am needing some feedback from some Salty Dogs on my latest project - the "Frankenrude 100" I am a collector of vintage fiberglass boats from the 1950s. I know my way around OMC 4V engines very well but have a couple questions that I need any insight possible.
The latest project involves putting together a motor that I have wanted to build for years. I am putting a 1968 Evinrude Starflite 100S inside the bonnet of a 1958 Starflite 1. I have done research for years on this and have all the parts to maske it happen. It isn't all that tough, you just need to know what parts you need - model - year etc.
The reason for this is to retain the vintage look of the '58 while having the power and economy of the 100S. Trust me, the 100S gets great economy compared to any of the 2 barrel V4s before 1969. Some call me crazy - some others want me to build them one for their old boats.
OK, so here is the questions:
I want to boost the compression on the 100S (they were pretty low from day 1). The heads from the 1969-1971 90C.I motors bolt right up, and the combustion chambers are better (smaller) I also want to mill these down around .060". I was wanting a cranking pressure of around 125-130lbs. I don't want to detonate the charge & blow out the pistons, so I'm wondering if anyone here has some ideas on what pressures the crossflows can tolerate without melting the slugs. Can someone help?
Also, the problem with carbon causing ring - jacking: I know the crossflows need to hit around 5grand+ at WOT to help recude carbon build up. That and good low ash TWC @ 50-1. However - even with those steps, i still see carbopn build-up on the top ring after just 10 hr. of operation. Any ideas here?
And lastly - yes I realize that this is all old junk. However it is my hobby, I have tons of NOS parts to build & keep it running. Plus I like the looks for my vintage boats. That's why I do it - its fun. Can anybody help with my questions?
Thanks,
Bruck