How to Install a Thru Hull Marine Exhaust System & Exhaust Tips
Question: Will A Thru Hull Marine Exhaust System Improve My Boat’s Performance?
The short answer is yes in most cases upgrading Marine Exhaust Systems to reduce engine exhaust back pressure WILL improve the overall level of performance and can also improve the life expectancy of the engine. We are asked on a regular basis as to what upgrade options are available for 4.3L and 5.0L engines specifically. In most cases the best starting point is always reducing exhaust back pressure. The reason being that most performance options are developed for the 350 and big block engines and therefore there aren’t that many available options for the 4.3L V6 and 5.0L V8 engines. Also keeping in mind that increasing performance comes with the risk of decreasing the longevity of the engine. There are many negative factors that play into increased performance including higher cylinder pressures, inducing water ingestion, etc that boat owners need to truly evaluate the best overall option for their particular case.
In general we like starting out with a thru hull exhaust system and then adding a performance exhaust system if even more performance is desired. Reprogrammed ECU’s are an option however there really aren’t any options outside the 350, 454 and 502 engines. Reprogrammed ECU’s if not reputable products can induce detonation into your engine which will lead to premature engine failure, etc. Since Mercruiser uses their own captive ECU platform there aren’t many good options for these products either. Changing internal engine components such as camshafts, etc is a very risky options because this effects the overall drive-ability of the boat not to mention greatly increases the risk of WATER INGESTION. With these factors at hand lets explore the options available for installing a Thru Hull Exhaust System.
Standard Thru Hull Exhaust Tips – This is standard Full Time Thru Hull exhaust with Open Tips. These are standard exhaust tips that allow your exhaust to be configured such that it runs from your engine directly out the back of the boat. You will need to be aware of any local noise laws that should be complied with when installing this type of system (see illustration).
Quick and Quiet II – This system is comprised of an exhaust diverter (minus the electronics) in combination with a exhaust silencer tip (see illustration). This system is a combination of performance and lower noise versus the open system. This is achieved by splitting the exhaust flow between the the existing Y-Pipe and out through the hull of the boat.
Quick and Quiet Plus - This system is comprised of combining the Captain’s Call Exhaust Diverter with an exhaust silencer tip (see illustration). This system is a combination of performance and lower noise versus the open system, while allowing all of the exhaust to be forced through the hull of the boat when a little more “kick” is desired.
Captain’s Call – This system utilizes Corsa’s patented Captain’s Call Exhaust Diverter and can be coupled with silencer tips (Quick and Quiet Plus) or with open exhaust tips for the maximum balance of performance and manageable noise. (see illustration).
Installation Tips – After deciding on which system is the best fit for you there are a few installation factors that need to be considered.
1. After cutting the holes in the hull of the boat where the thru hull tips will be installed, if your transom is constructed from wood we recommend sealing this exposed wood with a wood sealing product.
2. If you are installing thru hull tips but want to plug and leave the existing Y-Pipe we suggest cutting a plug piece of wood (use a standard 2×4) and seal it with resin, then install.
Request A Quotation
1. Measure your boat hull for the required space to install thru hull tips. Select this link to make sure you in fact have the necessary space required to install thru hull tips. Measuring Link. If you do not have the required space to install thru hull tips you may want to consider a side exit system.
2. Send an email to firstname.lastname@example.org outlining the year/make/model of your boat AND the engine. Make sure to include your engine model information as well as whether or not the engine exhaust system has 3″ or 6″ spacer blocks between the manifolds and risers.
Installation – 1992 Baja with Mercruiser 350
Installation Part 1 – 2006 Tahoe Q8 with Mercruiser 350
Installation Part 2 – 2006 Tahoe Q8 with Mercruiser 350