7.4L MPI in the 24??
05-27-2004 | 06:51 AM
#11
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Joined: Oct 2002
Posts: 5,246
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From: Ivoryton, CT
Re: 7.4L MPI in the 24??
What year is your boat?
I would not suggest installing an engine that is older than the boat.
For the same $$ or even a few more $$ a gen VI 454 mag is definitely the way to go. I know someone that dyno'd a gen VI 454 mag carb, 420HP @ 5000rpm. 200 hours is not a lot if the engine has been maintained properly.
I bought my 1999 310HP/7.4MPI with 37 hours for $3200. I would have payed an extra $2000 for a 454 mag if I was not a 2 boat owner at the time.
Upgrade on the exhaust and ECU would be worth about 20HP on a 7.4MPI.
As for my mods to the 7.4MPI, I changed the cam, had some head work done including springs to match the cam, swapped the cast exhaust for stainless marine, and re-calibrated the ECU. Gained 300-350rpm and 3-4mph. I would guess a 45-50HP increase. Still does not have the top end horsepower of a 454 mag, but I would bet it has a lot more low end torque.
I would not suggest installing an engine that is older than the boat.
For the same $$ or even a few more $$ a gen VI 454 mag is definitely the way to go. I know someone that dyno'd a gen VI 454 mag carb, 420HP @ 5000rpm. 200 hours is not a lot if the engine has been maintained properly.
I bought my 1999 310HP/7.4MPI with 37 hours for $3200. I would have payed an extra $2000 for a 454 mag if I was not a 2 boat owner at the time.
Upgrade on the exhaust and ECU would be worth about 20HP on a 7.4MPI.
As for my mods to the 7.4MPI, I changed the cam, had some head work done including springs to match the cam, swapped the cast exhaust for stainless marine, and re-calibrated the ECU. Gained 300-350rpm and 3-4mph. I would guess a 45-50HP increase. Still does not have the top end horsepower of a 454 mag, but I would bet it has a lot more low end torque.
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Patrick
Patrick
Last edited by Pat McPherson; 05-27-2004 at 07:27 AM.
05-27-2004 | 08:38 PM
#12
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Joined: Aug 2002
Posts: 5,658
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From: IL
Re: 7.4L MPI in the 24??
So you would go with the Mag with the higher time?
The 7.4 is a 2002, the Mag is a 1999 which matches the boat year.
The motor is in the classifieds, the guy seems like a fanatic. Which is good.
The 7.4 is a 2002, the Mag is a 1999 which matches the boat year.
The motor is in the classifieds, the guy seems like a fanatic. Which is good.
05-27-2004 | 09:42 PM
#13
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Joined: Oct 2002
Posts: 5,246
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From: Ivoryton, CT
Re: 7.4L MPI in the 24??
For the same money or +$500, I would buy the 454mag.
The difference between 120hours and 200hours does not seem that significant to me being that the engines are stock packages.
In my opinion the 454mag is a better match for the way you have rigged your boat; full hydraulic steering, K-planes...
With the 454mag the boat will top out 6-8mph faster than with a 310HP/7.4, and crack 70 without question.
Good Luck Selling Her, She is an Awesome Looking Boat!
The difference between 120hours and 200hours does not seem that significant to me being that the engines are stock packages.
In my opinion the 454mag is a better match for the way you have rigged your boat; full hydraulic steering, K-planes...
With the 454mag the boat will top out 6-8mph faster than with a 310HP/7.4, and crack 70 without question.
Good Luck Selling Her, She is an Awesome Looking Boat!
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Patrick
Patrick
07-25-2004 | 11:01 AM
#16
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Joined: Jun 2001
Posts: 1,213
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From: Tulsa, OK, Grand, Beaver, LOTO
Re: 7.4L MPI in the 24??
I'd go with the mag, the hours are nothing, it matches the yr and the overall intent of the boat. Someone could add a whipple and have a screamer if they chose to.
