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Discussion Starter · #1 ·
Have a 05 232 6.2L Procharger 5 psi with Intercooler...1.65 Bravo Drive Was running 13 7/8 23p Vengence 5100 to 62 on Gps Before procharger...Tried a mirage plus 15.5 25p to 4800 at 61 gps hole shot and mid range is Incredible..2000 rpm to 4500 Is as quick as it can be.... Can pull two skiers up with 8 people 2 coolers and alot of beer...But my top end sucks...Top end is why I installed the charger to begin with...One more note: at 4800 Is only 65-70% throtle More throttle does nothing and revs up and down 100 rpm like it is hitting the rev limiter. Guessing tach may not be right Installed procharger last fall did not run till this summer.... Looking At a smaller dia. mirage (Dont think I have the upper end torque to spin a 15.5 dia. prop) or Some other kind of speed prop Any suggestions... 62-63 mph Stock.. believe should be able to get to 70 or better What am I doing wrong :( Any advise would be greatly appriciated...

Danny
 

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Discussion Starter · #3 ·
And More pics

Installed EGT's In cylinders 1 and 8 To get an idea of Air fuel mixtures constantly and mounted two Digital Temp controls in the dash for readouts probably going to wire and program them to shut spark down If cylinders go lean...
 

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I'm no expert... but it sure sounds like you're hitting a wall on air flow somewhere... exhaust is first, then heads? cam? etc... figure out where the bottleneck is. clearly the factory manifolds are a huge one...
 

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Autoden , the 6.2 is an excellent engine with good internals even with the hypereutectic pistons under 5 pounds of boost. As I see in your picture you still have the stock exhaust system. The stock system is good to 5200 rpm , however with a supercharger installed you should at least remove the turbulators if you haven't already done that.The stock manifold chokes your scavenging big time.An aftermarket manifold/riser system from Imco , Eddie Marine, Kodiak or Revolution would gteatly improve your setup.
 

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Discussion Starter · #8 ·
Ok ya got me what heck are turbulators and how are they removed...? Cant really do much more This year, with the exhaust...Budget Blown all to hell..But what about a prop Cleaver, Mirage, Chopper, Bravo..And the


Ps Checked throttle linkage before even checked Full range of TPS All Good... Probably right though (with the exhaust) cant get more air in without getting more air out...
 

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The turbulator gasket is between the exhaust manifold and riser. When you remove the riser you'll see how small the exhaust passage is, further reduced by the turbulator. The aftermarket manifold exhaust holes are almost twice the size of the stock ones.I'm turning Bravo 1 26P props through 1.65 ratio. Once you got your set up right I think you could go to B1 28P .
 

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The 6.2 using a turbulator gasket that's different in shape from other dry joint gaskets. It has water passages incorporated that fits exclusively to the factory stock manifold and riser.What you can do is, take the gasket out and grind the lip off to open the passage to match the riser's opening and put the modified gasket back. Your next bottleneck is the "Y" pipe that routes exhaust through the prop .Remove the "Y" pipe and block off the exit with a plate that's available from any merc dealer. Drill holes in the transom for tips , seal the opening with resin to make sure you won't have rot developing there.Get some rubber exhaust hose from West Marine
and upgrade the exhaust system later when funds available.If you don't want to deal with the "Y" pipe now, you should at least remove the exhaust rubber tube [ held by one clamp only , a small 1/4 drive with universal would work] that connects between the drive and transom assy outside routing the exhaust gas through the drive and prop hub. This may allow the gas escape a little better while on plane already and the supercharger pushing harder.
 

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Discussion Starter · #12 ·
Im not running Thru the prop...Have 4" goin straight out the back But will take a look into the riser Assem. Thanks
Danny
 

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Discussion Starter · #13 ·
What a Joke! and a waste of putting in 4" pipes and tips
The Exhaust Risers were Necked down With a plate Gskt to 1.87X 1.47 Rec. port Thanks For the info Defi. need New Exhaust Manifolds.......
Thanks Again..
 

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autodan7 said:
Have a 05 232 6.2L Procharger 5 psi with Intercooler...1.65 Bravo Drive Was running 13 7/8 23p Vengence 5100 to 62 on Gps Before procharger...Tried a mirage plus 15.5 25p to 4800 at 61 gps hole shot and mid range is Incredible..2000 rpm to 4500 Is as quick as it can be.... Can pull two skiers up with 8 people 2 coolers and alot of beer...But my top end sucks...Top end is why I installed the charger to begin with...One more note: at 4800 Is only 65-70% throtle More throttle does nothing and revs up and down 100 rpm like it is hitting the rev limiter. Guessing tach may not be right Installed procharger last fall did not run till this summer.... Looking At a smaller dia. mirage (Dont think I have the upper end torque to spin a 15.5 dia. prop) or Some other kind of speed prop Any suggestions... 62-63 mph Stock.. believe should be able to get to 70 or better What am I doing wrong :( Any advise would be greatly appriciated...

Not an expert at all on superchargers but it sounds like you are running out of air on the top end, I've chased this problem on my carbed motor, wait I'm still chasing it, but I was actually thinking about installing a procharger on mine but was afraid of the added complications, good luck! Let us know what you find
Danny
 

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Discussion Starter · #15 ·
I have found that prochargers are a pain in the Arse... Ati is of very little help And If I were to do it over again A would have installed a Wipple...Since they are the only ones With The R and D to make it work right with the late model stuff like mine.... Got to 5100-5200 At 63 mph this weekend Burned a plug on cyl 7 And really happy that is all it was... Prob. detination problems Hitting 1450 cyl temp at 5100 wot bumping the rev limiter....And richer that crap at an idle Seems to be a common problem....Fuel curve is all jacked up Boost power told me That a 2bar map cant be installed and not to mess with it....And they could change the rev limit and add a little fuel on top end But all they could do For almost 500$ Still going to have problems because Map sensor is still going to be giving false readings...Going to try a external tps and map controller...To set a new fuel curve and Get a better exhaust system. Tried varible resister on the map to see if it would help It did on the low end but jacked up the upper end and over all was better in some spots worse in others...Not a good idea...Still dont have any answers on a prop for top speed, mirage 25p with 14% slip hitting the rev limiter Not happy.....So in conclusion Dont atemp this project on a budget (Throw that Idea out the window) and 7K for a wipple doesnt sound bad considering all the stuff you have to add to the procharger to make it work Plus the Time involved....If you are fuel injected...Carbed dont think you will have as much problems....
 
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