Cat: Quad vs Twins
10-31-2019, 12:32 PM
#1
Admirals Club 
Thread Starter
Cat: Quad vs Twins
I am considering an engine package for a new Cat. I cannot make up my mind between quads and twins.
Please share with me your thoughts and opinions if you have had one or the other or both. Or if you have experience on Cat hulls with quads and twins.
It would be less HP with twins. Either 850 or 900 hp. vs 1200 hp. Maybe 7 or 8 mph difference top end?
I’ve e narrowed it to:
Quad 300 V8 Mercs
Twin Merc 450’s
Twin Yammy 425
Please share with me your thoughts and opinions if you have had one or the other or both. Or if you have experience on Cat hulls with quads and twins.
It would be less HP with twins. Either 850 or 900 hp. vs 1200 hp. Maybe 7 or 8 mph difference top end?
I’ve e narrowed it to:
Quad 300 V8 Mercs
Twin Merc 450’s
Twin Yammy 425
10-31-2019, 12:57 PM
#3
Senior Member
Originally Posted by MakoMyDay
Kind of depends on the particular boat and size......
10-31-2019, 01:07 PM
#5
Senior Member
Something else to keep in mind if you plan on running long distances. If you lose one motor on a twin setup it will be a slow ride home. It doesn't happen often but it is a benefit of quads over twins.
Likes:
10-31-2019, 01:11 PM
#6
Senior Member
Long runs or relatively short runs to fishing ground? How do you load the boat? if often loaded down heavy then maybe quads, then there’s the fact that I’d much rather come in from 80miles on 3 engines than 1 engine.... basically if making long heavy loaded runs I’d lean towards quads... but spending your money instead of mine is easy I guess haha
10-31-2019, 01:31 PM
#8
Senior Member
Looking cool cost a lot of money, being cool cost even more!!!!
10-31-2019, 02:18 PM
#9
Depends on the boat, I try to select the best power for 90% use on the boat and the boats characteristics.. If you don't care about wide open speeds twins might be the way to go but if you want to cruise at 55 you might want quads. As said above quads might be nice when you loose a motor but you will have 50% more chance in loosing a motor with quads versus twins.
10-31-2019, 03:39 PM
#11
My take is this:
You’re buying a boat that has the performance potential of the quad package. The only reason not to get quads is if the upfront expense or ongoing additional maintenance expense is beyond your budget. Otherwise, quad that bitch and get the full potential of the hull.
You’re buying a boat that has the performance potential of the quad package. The only reason not to get quads is if the upfront expense or ongoing additional maintenance expense is beyond your budget. Otherwise, quad that bitch and get the full potential of the hull.
10-31-2019, 03:41 PM
#12
Senior Member
Tough decision - At the risk of raising the ire of my good friend alloyboy (again) and as the number of sleepless nights (tossing and turning) is becoming the norm...sometimes...just sometimes...
a pair of 7's trumps four 6's or 8's...
noa...have you got the minerals...
https://www.youtube.com/watch?v=qcVH...ature=youtu.be
a pair of 7's trumps four 6's or 8's...
noa...have you got the minerals...
https://www.youtube.com/watch?v=qcVH...ature=youtu.be
Likes:
10-31-2019, 05:09 PM
#13
Senior Member
Join Date: Oct 2009
Location: One bridge south of Clearwater Beach
Posts: 1,663
Likes: 0
Received 979 Likes
on
483 Posts
I'm getting ready to build a new cat (not requiring quads), but have been looking at different sizes and combos trying to figure out what I want to run. From my research and experience, quads come into play when you get to the 35' length or longer. I do know a guy that was running twin 350's on a 40' cat and went to quad 300's. The economy went up .3-.4 mpg with the quad 300's and the top end went up about 4-5 mph. I know that doesn't help as much since your looking at twin 425's. Personally, I prefer naturally aspirated, so the 450's are out in my book. With the extra weight, drag and cost of quads, I would probably go with twins....but I'm not a WOT person, I shoot for the most economical, comfortable cruise that gives me decent speed. However, I can see the appeal of quads to a tournament guy that wants to go balls out all the time and be able to get home as quickly as possible if one engine goes down.
Likes:
10-31-2019, 05:43 PM
#14
Admirals Club
Originally Posted by Drew46
This is probably as shallow a response as I have ever provided, but Quads look so much cooler while twins can look very pedestrian.
10-31-2019, 07:16 PM
#15
Senior Member
As most are pushing for quads I’ll throw in my opinion.
Twins are my choice. Less potential for things to go wrong with less equipment. This opinion comes from flying planes with 4 and 2 engines. More engines more chances for things to go wrong. This is why most airliners are now twin engine.
Twins are my choice. Less potential for things to go wrong with less equipment. This opinion comes from flying planes with 4 and 2 engines. More engines more chances for things to go wrong. This is why most airliners are now twin engine.
10-31-2019, 07:42 PM
#17
Admirals Club
Thread Starter
Originally Posted by MakoMyDay
Kind of depends on the particular boat and size, but I've had two with twins and am now building a quad 300 merc 42 if that tells you anything.
it the 35 Inv Cat
10-31-2019, 07:43 PM
#18
Admirals Club
Thread Starter
Originally Posted by frank1861
Something else to keep in mind if you plan on running long distances. If you lose one motor on a twin setup it will be a slow ride home. It doesn't happen often but it is a benefit of quads over twins.
10-31-2019, 07:49 PM
#19
Admirals Club
Thread Starter
Originally Posted by ucf_motorcycle
As most are pushing for quads I’ll throw in my opinion.
Twins are my choice. Less potential for things to go wrong with less equipment. This opinion comes from flying planes with 4 and 2 engines. More engines more chances for things to go wrong. This is why most airliners are now twin engine.
Twins are my choice. Less potential for things to go wrong with less equipment. This opinion comes from flying planes with 4 and 2 engines. More engines more chances for things to go wrong. This is why most airliners are now twin engine.
10-31-2019, 07:53 PM
#20
Admirals Club
Thread Starter
thanks for the feed back guys. its helped me decide.
Quad Merc 300
74 mph.
of course top speed ain't all that but i want to cruise at 45-50, maybe 55
fishing grounds are 80-120 miles round trip
looking at 35' Inv Cat
Quad Merc 300
74 mph.
of course top speed ain't all that but i want to cruise at 45-50, maybe 55
fishing grounds are 80-120 miles round trip
looking at 35' Inv Cat
