2001 Volvo Penta GSI Performance Parts (TBI & Exhaust)

Lubak572

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I bought my first boat Four Winns 298 Vista with twin 5.7 Gsi's, and was wondering if aftermarket performance parts are available in regards to the TBI and exhaust? I was going to pull those 17 year old injectors and send them out somewhere to be cleaned/serviced, and i thought while i had them out I would maybe rebuild the whole TBI. I see you can get ported TB's, TB spacers, injector spacers, and even bigger injectors from companies like CFM Tech, RV Morse, SPR Performance, etc.. Also was toying with putting K & N flame arrestors on and when i replace manifolds & risors going with a aftermarket set-up like Hardin marine or something. Any thoughs on this? I just figured when replacing OEM parts, why not go with performance ones or lighter, stronger, improved ones. Just don't want to keep it reliable.
 

Scott Danforth

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Welcome aboard

the exhaust would get you about 3-5hp at most.

Any other changes will require a remap for your ECM. if you ditch the entire TB setup, pull the motors, rebuild them as 383 strokers, go with MPI..... then you would be making some power you would notice.

bolt-ons have almost no performance gains until you change the cam and pistons at a minimum.
 

alldodge

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Agree, and will add, the air intake is limited by the head and intake, the TB can already pass more air then the motor can take in. So doing anything to the TB without doing something to the motor will change nothing. This also includes the flame arrestor
 

Lubak572

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Do you think a remap of the ECM is needed for like a Hardin Marine exhaust, and TBI improvements. i just figured if I was in there anyways to do it now. Motors have around 300 hours and run good. I have all the manuals/tools and Diacom software- just can't write to ECM probably should have went with MEFIBurn software, I have modded a lot of other motors- first Marine one though. When it comes to rebuild i definately will go with better heads and cam maybe even 383. But wanted to start now on the intake and exhaust. Don't want to to it twice ($$$).
 

Scott Danforth

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no, exhaust changes do not require an ECM change

300 hours is not even broke in yet, I wouldnt do anything to the motor other than maybe manifolds/elbows. and for those, I would simply use Barr marine vs OEM volvo and that is ONLY if you boat in salt water. if you boat in fresh water, change oil, add fuel and go boating.
 

Lubak572

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Boat originally was in florida for a year or 2 then utah and then colorado for the last 7 or 8 years. Now in Michigan so fresh water for most of its life. Don't know if they are the original mainfolds/risors. Don't want to risk it was going to replace them soon. When i do I would rather have a lighter/better performing set -than those heavy stock cast iron ones. I also thought about adding captains call exhaust.
 

Scott Danforth

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inspect them before you buy anything. doesnt pay to replace them unless they need to be replaced.

captains call is simply a noise/headache maker unless you are running a big block. then it gains you about 10-20hp on a built (non-stock) BBC

the volvo manifolds are actually really good from a performance stand-point (better than Mercruiser). you wont gain more than a few HP at most and that would be from the stainless riser elbows mostly.

However if you want to spend $2500 on performance manifolds and risers for each motor and another $2500 on captains call exhaust for each motor...... go for it.
 

Lou C

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I would remove the risers and check the sealing surface, if it looks good fine, if its a bit eroded, you can have them decked at machine shop which should be a lot cheaper than replacing them (each engine is about $700 or so, Barr units, Volvo OEM probably a good deal more). I used the Barr units on my 4.3 and the quality was pretty good with very flat sealing surfaces...
 

Lubak572

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How much do the stock ones run? How long do they last for a boat sitting in fresh water from April to October?
 

alldodge

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How much do the stock ones run? How long do they last for a boat sitting in fresh water from April to October?

I long time, my 95 Rinker has never been changed, and the ones removed from my Formula are sitting in the shop and have no issues
 

Scott Danforth

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How much do the stock ones run? How long do they last for a boat sitting in fresh water from April to October?

the stock units off my '88 boat were still usable when I removed the motor 2 years ago. the boat was moored most its life in Lake Michigan, then ran for 4 years in the salt down here (Flushed after every use)

If I didnt want more power replacing my SBC with a BBC, I would still be running the stock manifolds.
 

Lubak572

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Thanks for the replys, for now I may just pull risors and inspect. I am going to changed the thermostats and impellors anyways and will check the internal cooling passages and decide from there.
 

BRICH1260

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This might be a good time to pull the drives also and have a look at the U-joints and bellows.
 

Lubak572

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This might be a good time to pull the drives also and have a look at the U-joints and bellows.

Yes they will be coming off this year, I already bought both bellows and an alignment bar and F6 props (correct ones). What else on the drives need to replaced/serviced? I do plan on improving/replacing that crappy plastic zerk tube.
 

BRICH1260

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Yes they will be coming off this year, I already bought both bellows and an alignment bar and F6 props (correct ones). What else on the drives need to replaced/serviced? I do plan on improving/replacing that crappy plastic zerk tube.

Or you can just install a greaseless (maintenance free) gimbal bearing, plug and remove the plastic tube. I might also suggest a pressure and vacuum test on the drive while it is off. Also if you like tearing things apart, separate the drive halves and replacing the rubber O rings in between.
 

Lubak572

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Or you can just install a greaseless (maintenance free) gimbal bearing, plug and remove the plastic tube. I might also suggest a pressure and vacuum test on the drive while it is off. Also if you like tearing things apart, separate the drive halves and replacing the rubber O rings in between.

Yes I plan on pressure and vacuum testing. Hopefully my Mityvac tool can be used for that, just need proper adaptors I suppose. Wasn't really planning on pulling the upper and lower halves unless needed. What else should be replaced on the transom to drive mounting surface if any? I plan on checking/ possibly switching anodes to magnisum for Great Lakes.
 

BRICH1260

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Halving the drive is not routine maintenance, only if you might find a pressure leak. I did mine this post season, just to better learn the drive. There will be a large Oring that is sandwiched between the drive gear housing and the pivot housing that you might as well change, it keeps in going cooling water from pulling air into the system. Might as well replace it while you are there. Definitely get a new set of anodes.
 
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