go procharger or not

[dogschool]

I am considering adding a procharger to my recently rebuilt
454mag in my '89 251 Convincor, is there enough room for it
in my engine compartment? I'd appreciate any feedback
positive or negative. Is the effort worth the speed gains etc..
Thanks!

 

[Gimme Fuel]

I would say that you have enough foom in your engine compartment....those don't take up that much room. And the effort is worth the speed gains....45-50% more horsepower is always worth it. A procharged 454 in your boat would run very well if set up right. Are all of your engine internals forged? Are you running stock compression? If yes to both then it should work well. The only downside of the whole thing is the cash that they cost.

 

[dogschool]

Thanks Gimme, there have been performance upgrades
to my 454 mag - hi perf heads - roller rockers - intake
and exhaust - 850 holley carb - new cam - internally
everything is new with the rebuild. More hp should allow
me to run a bigger 4 blade prop (3 blade 23p SS now)
without losing rpm - what kind of speed gains can be
expected - I basically run 65mph wot allday - have surpassed
66 and once even seen 67 gps (low fuel /wind aided/ light chop).
What would be considered a good deal as far as cost of
a procharger for this boat? Easy to install?

 

[Gimme Fuel]

Dogschool, I would have to look up the prices. I would say 4-5 thousand is average for a stage I (non-intercooled). It might be a little cheaper for you seeing as you are carbed and not EFI. And since you are carbed, I would go with a roots style supercharger and a new cam for superchargers. Those have way more torque and response than a centrifugal procharger and besides they sound waaaay cooler. That would be quite easy for your setup. Either way I would recommend the extra money for an air-water intercooler (stage II with procharger). that reduces engine and egt temps drastically and yields a nice extra gain in HP due to the cooling of the intake charge. If you were an EFI motor I would go with a procharger but on a carbed motor I would go with a roots style blower......that's just my .02

 

[boatn70]

for the most part I agree with Gimmefuel.
however, with a roots charger your may be limited on height to your hatch. I can assume a procharger and intercooler with fit just fine. I recently removed my carb setup procharger to sell the boat.
key items i would recommend:
cam selection (if it works N/A it will work with PC but may leave HP on the table)
exhaust valves (i ran stock valves with no issues but most say inconnnel)
intercooled (with procharger definately a must)
carb tuned (use Nickerson!!)

as far as speed gains my 502 in my boat went from 73 to 83 with that being the only change besides prop.

i also would comment on the roots blower and torque. depending on how you drive your boat sometimes it could take a toll on the bravo drive. i have heard second hand that with the lowend TQ of whipples and roots type blowers that its tough on the drive whereas a procharger comes on later in the rpm range and is less stressful.

i have had absolutely no issue with mine regarding the drive. the only issue i had was because my cam was designed very poorly and was wrong for any marine use! my fault!

my procharger setup may be for sale too! I have to organize all parts etc and clean them up since removal though. I had probably 3000.00 into it.

 

[lcboater]

give Jason Kunkel a call, he is an expert on pro chargers.

 

[Gimme Fuel]

I agree with boatn70.....cam selection is key to making a blower as efficient ass possible. With a blower setup, you want to reduce overlap so you are not blowing your intake charge out the exhaust and usually the lift on the intake side does not have to be that extreme because the supercharger does the work of loading the cylinder versus using the vacuum in the cylinder to pull the charge in like on a naturally aspirated motor. I am pretty happy with Bob at Marine Kinetics so far. He is very helpful and takes into account every detail of your boat when grinding a cam. I have yet to see what numbers it will run on mine but I think he is a better choice than calling comp cams or something.

 

[Big Red]

I would leave it alone and ride. If you want more power I would build another engine on the side and stick it in when its done. That would really suck blowing your engine in the middle of the summer. Its not as easy as 1 2 3 putting on a pro Charger their will be a lot of test time. I would gather all my parts for another engine build. Dogschool I know how you like to go all over boating and with "hop ups" comes down time. Its already spring and your thinking more speed so your going to waste alot of your boating this year on down time. This should have been done at the end of last summer.

 

[dogschool]

I would leave it alone and ride. If you want more power I would build another engine on the side and stick it in when its done. That would really suck blowing your engine in the middle of the summer. Its not as easy as 1 2 3 putting on a pro Charger their will be a lot of test time. I would gather all my parts for another engine build. Dogschool I know how you like to go all over boating and with "hop ups" comes down time. Its already spring and your thinking more speed so your going to waste alot of your boating this year on down time. This should have been done at the end of last summer.

Thanks Red, I needed that! I don't need any down time now for sure!!
However I do want to collect as much info/knowledge on the matter
as possible because I can see this happening, maybe even this fall
when the boating season nears an end. You have also given me
something else to consider with the 2nd engine build idea..hmm..
Though I am looking for a quick/easy hp boost - I am not sure why
but I am on a quest to run over 70 mph, and kind of afraid that when
I get there I'll then need to run 80..lol..I got bit by the need 4 speed
1st on my bike - now on my boat!

 

[SCT]

D-school, you have to think about resale, also. It seems like most people shy away from SC engines in a used boat.

Good luck-

 

[ross]

D-school, you have to think about resale, also. It seems like most people shy away from SC engines in a used boat.

Good luck-

there is a valid point! i'm with you on that one

 

[Lakeside Restorations]

You never really just bolt on a SC.. At least it shouldnt be done that way. Procharger stuff is built pretty good, but I am not a fan of their stuff on the late model more current EFI stuff or on carb applications.. I think thier best years were for the black mag efi stuff 350/454/502.. Outside that for those few years I think there is other stuff that is better suited.. If you are carbed I wouldnt recccomend a Procharger to begin with. Sure it will work, but carbs operate better as pull thru units rather than blow thru. Otherwise there is a bit more involved and messing with a carb in a box on a boat is a little bit of a PITA at times. If you are going to stay carb you would be better in my opinion running a blower shop, whipple or other screw style blower. I also reccomend using an intercooler.. More HP & its made even safer than running without one. THere is a lot more to running boost than most think. Every little thing must be taken into consideration when adding one. If done properly they can be reliable & turn key for the most part. I have been building them and running them for many years with our shop... Jamie / Lakeside

 

[throttletherapy]

Thanks Red, I needed that! I don't need any down time now for sure!!
However I do want to collect as much info/knowledge on the matter
as possible because I can see this happening, maybe even this fall
when the boating season nears an end. You have also given me
something else to consider with the 2nd engine build idea..hmm..
Though I am looking for a quick/easy hp boost - I am not sure why
but I am on a quest to run over 70 mph, and kind of afraid that when
I get there I'll then need to run 80..lol..I got bit by the need 4 speed
1st on my bike - now on my boat!

i agree if you can build another motor with forced induction and not touch the 454, i personally would take that route. be careful to because if memorie serves me right in 89 the big blocks came with the alfa one drive, could be wrong but if it does you will HAVE to change it out! I also have a gtx a 98 with a 540ci that i built from ground up. there is nothing like true cubic inch. mine runs 83 on gps

 

[dogschool]

i agree if you can build another motor with forced induction and not touch the 454, i personally would take that route. be careful to because if memorie serves me right in 89 the big blocks came with the alfa one drive, could be wrong but if it does you will HAVE to change it out! I also have a gtx a 98 with a 540ci that i built from ground up. there is nothing like true cubic inch. mine runs 83 on gps

Thanks for the advice throttle! My '89 Convincor has a Bravo outdrive
and I am not sure but I think most if not all late 80's Checkmates with
454 mags do.

 

[dogschool]

You never really just bolt on a SC.. At least it shouldnt be done that way. Procharger stuff is built pretty good, but I am not a fan of their stuff on the late model more current EFI stuff or on carb applications.. I think thier best years were for the black mag efi stuff 350/454/502.. Outside that for those few years I think there is other stuff that is better suited.. If you are carbed I wouldnt recccomend a Procharger to begin with. Sure it will work, but carbs operate better as pull thru units rather than blow thru. Otherwise there is a bit more involved and messing with a carb in a box on a boat is a little bit of a PITA at times. If you are going to stay carb you would be better in my opinion running a blower shop, whipple or other screw style blower. I also reccomend using an intercooler.. More HP & its made even safer than running without one. THere is a lot more to running boost than most think. Every little thing must be taken into consideration when adding one. If done properly they can be reliable & turn key for the most part. I have been building them and running them for many years with our shop... Jamie / Lakeside

Thanks Jamie, I may be in touch to discuss this further! John

 

[throttletherapy]

Thanks for the advice throttle! My '89 Convincor has a Bravo outdrive
and I am not sure but I think most if not all late 80's Checkmates with
454 mags do.

thats cool, that is less expense!

 

[bigsbetter]

Hummmm, I don't have to think about this one! I say do what I did and get a Holley/Wieand 177 blower. You'll increase your speed 8-12 mph. for under 2500 bucks. When I first put mine on my bone stock 454 330 horse, I gained 10-11 mph. After tuning and stuff I've gained a total of 15mph. And that's all with a carb. that was too small. CAm selection is important. Stock cams work well with these small blowers. If you've got a radical cam it won't work as well. If you've got the stock Mag cam, that may be the same cam Mercruiser used in their 525SC engine.

 

[dogschool]

Hummmm, I don't have to think about this one! I say do what I did and get a Holley/Wieand 177 blower. You'll increase your speed 8-12 mph. for under 2500 bucks. When I first put mine on my bone stock 454 330 horse, I gained 10-11 mph. After tuning and stuff I've gained a total of 15mph. And that's all with a carb. that was too small. CAm selection is important. Stock cams work well with these small blowers. If you've got a radical cam it won't work as well. If you've got the stock Mag cam, that may be the same cam Mercruiser used in their 525SC engine.

Thanks for chiming in Bigs, and I must admit I like your reply the best!
I am trying to weigh the pros and cons and if what you suggest is at
all doable I just might, like asap! I have a new stock cam, motor is
freshly rebuilt, hi perf heads, roller rockers, hi perf intake, 850 holley
carb etc..did you have any clearance issues in the engine compartment?
I suspect that since I have a fresh rebuild this is the perfect time for
me to make such a move, but I don't want to be turning wrenches once
the boating season begins! Did you do yourself or have a shop do it?

I appreciate any and all shared input, thanks to all that chime in!

 

[bigsbetter]

I did mine myself. I bought the boat in March 3 years ago, drove it stock for 2 mounths and in May or june decided to do the blower thing. I was down for about 2 weeks. Yes their is clearence issues. I had to raise my entire hatch 3 1/2", and cut the fiberglass behind my rear seat where the blower snout goes. You can't see any of that. I have jad zero problems with the setup. Turn key every time, never a mishap.

 

[Moodswing]

502 EFI prochargerII

My 502 procharger motor as been bullet proof for the past 9 yrs. It was built by Bill Shumaker at Shumaker Performance in Greenwood In. This guy knows prochargers and the required parts to make them run long term. Other than plugs, wires and Mobile 1 oil I have had no other issues. I will tell two downsides, I have replaced the Bravo drive twice and have a white hull I do get smoke deposits under the swim platform. The motor does have an inter cooler, 16 QU oil cooler, bigger cam, the block was balance and printed and I run no themastat so the boat never run hot.
The hp range was around 715 when first put together ( sure after a few yrs its down ) the motor will turn 6000rpm but I limit it to 5600 turning a 30 pitch Bravo lab finish racing 4 blade at 86.7mph on gps. I could turn a bigger pitch but 86mph is fast enough for me and since the motor has lasted me for nine yrs I don't want to buy anymore out drives. The thing I love about a procharger vs root blower is the midrange. At 7 lbs of boost the 35-75mph is very impressive. As far as sound of "motor" I have had folks tell me they could tell it had a blower, with Checkmates and thru hull above the waterline makes for a great sound. Or maybe folks just see the 5/8 stream of water shooting out from under the swim platform.
The boat is a 1996 253.