Blower for a 500hp
 

I am kicking around the idea of a blower for my carded 500. I am not sure what would be the best way to go.

I would like to get something that is gonna put between 650 and 750 hp i am planning on adding a set of brodix bb2 heads and i will be running the Cr 741 cam also emi exhaust.

As for the cost i just want it done write and want the best blower for my motor i am thinking about a tbs 250 from the blower shop since i wont have to have the hatch scoop. I am open to what ever just want to do it right the first time.

The boat is a 1998 25 outlaw carbed 500 fresh rebuild, motor is still out of the boat.

Also what prop should i be watching for or thinking about? I was thinking mirage plus 27p

You'll definately need a 4 blade, probably a Bravo in the 28-30 range.

Should i replace the stock pistons and if so what would be the best bet for what i want to do.

bump anyone

The stock pistons will work fine. Some JE's would be better.

I guess it all depends. Are you doing a full rebuild?????? If you are replace them, if not, leave them.

Ok thanks

couple of my friends have 500's with B&M 250 blowers on them (I think that is the blower model, but could be wrong). The one's that have that setup with only 1 large (CFM) carb seem to have issues with getting them to idle. A couple of them have 2 smaller carbs on top and those seem to idle much better. I guess with only one large carb, the air velocity is too low and doesn't give very good signal for idle circuit.

Thanks Does anyone else have comments about the carb . The blower i am looking at is the 250 from blower shop with a holey dom 1050. and a aero 1000.

You can make it work with the single 1050.Im thinking two smaller would be to much carb with a 250. The idle circuit has to be played with ,air bleeds.Most forget about air bleeds and only adjust the idle enrichment screaws.If your past 1.5-2 turms out the air bleeds are incorrect. A larger air bleed will give you a leaner mix while a smaller gives you a richer mix. This is the opposite of fuel jets. I would recommend
EGT gauges and depending on what pistons your run you can adjust idle and top end.Lean conditions happen real fast with a supercharged engine.Be careful!! :drink:

My 1050 idled just fine on my warmed over 525SC. It did take some adjustments of the air bleeds a few times to get it just right. The aeromotive 1000 is probably overkill, but will work. Just make sure to wire it with an oil psi cut off switch.

Here is the link to the blower i am looking at. So let me know what you think is the price right good choice for my motor ect.

http://forums.boatfreaks.org/showthr...ghlight=blower

$4250 seems overpriced for used. Full retail on the Blower kit is $3300 new. The rest of the stuff brand new is maybe $2000. BTW, is it a Marine carb??????

Its maybe 20% off of brand new.

Not new but it will get youstarted.

http://www.offshoreonly.com/forums/s...-up-cheap.html

Probably need a smaller upper pulley for that engine and those heads to make boost.

Realy, you don't need heads that big and that is going to be a good cam. If you are going to spend the cash, you should just call or PM rmbuilder and let him get you a custom cam that will do what you want.

750HP out of a 250 blower and that displacement is going to be real hard to do without using a tiny pulley on top and a giant pulley on bottom. That creates a lot of heat and that takes away from reliablity.

600 is a very reasonable and reliable expectation for that setup you are considering. Maybe a few more.

If you are going for the extra power, I highly suggest the intercooler also.

1 Dominator actually makes a little more and better power in the mid range than dual carbs on an engine that small.

If you are doing a total rebuild and starting from scratch, use JE piston #257949. This is a very low compression piston, 7.8:1 and use the smallest pully they offer on that blower kit with an 11-1200 Dominator and have Bob build you the right cam and I think you might get into the mid to low 700's. This should yield around 6-7lbs of total boost at WOT. You will need a longer rod for that combo though, but that is a good thing as this will give you a better angle on the piston travel and allow more rpm's safely.

I have used a very similar combination on a 468CI engine with a net 650+- HP at 5800rpms. You will have plenty more CI's to play with so it should get you there. IMO you shouldn't need bigger than a 330 +- head. Go with a silod roller for a little more power.

Good luck.

Oh and if it is adjusted right, the 1050 should idle better on top of the blower and have a better frequency.

I have already purchased the cam and lifters. They are actually already in the motor. The motor is already put back together. The stock heads have been freshened up.

This was a mix up between me and the motor guy so i only want to take apart what i should. Like if you guys say you really should change the pistons then i will, but if what i got will work then i wont mess with them.

As for the inter cooler i really do not want to have a scoop i have 6 kids and a Ole lady that's always laying back there or something. I was told to use the chiller. That i would need the scoop.

For the heads i have not purchased a set yet so i am open to suggestions i think i want to use brodix not sure what size. If buy using the blower and heads i would only see 600 hp i wont buy both i will buy heads or blower. To me the money spent for 600 hp or a little more is not worth 7000.00 I thought the heads would give my 575 hp and with the blower and heads i would be 700 to 750.

I was also looking at this setup but not sure, so if you guys think this is a better deal please speak up.

http://cgi.ebay.com/ebaymotors/ws/eB...m=140287151756

What kind of hp with a good set of heads with no blower? Arre the heads a absolute must with the blower, or would the stock heads be fine. I am not so worried about hp just wana run 80 I was thinking it would take around 700 hp to get there.

I just want to do this right the first time no short cuts. If you cant tell i am pretty new to all of this so i apologize if i am asking allot of dumb questions. I just have no one else to ask except the good people of oso. I THANK ALL THAT ARE HELPING ME!!!!

We have a B&M 420 That will make you power.

That blower would suit the 502ci motor much better than the 250. It would make the same boost at a lower rpm and make less heat.



Darrell.

Please feel free to contact me. I can put you where you want to be and save you money on the components your looking to purchase.

Here is my email [email protected]

I was also looking at this setup but not sure, so if you guys think this is a better deal or choice Please speak up.

http://cgi.ebay.com/ebaymotors/ws/eB...m=140287151756

That 420 would put you where you closer to where you want to be that the 250.

You are going through the same thing most guys go through. THey start building an engine and then they want to switch boats mid stream.

The key to a good engine is designing exactly what you want and then building it. Generally if you change 1 thing, there are several other things that have to be changed to match.

Dean, Mrhorspower has given me good advice in the past, you should call him he is a distributor for most lines of heads.

I have found out the hard way about changing things ,that's why the whole project is on hold till i can figure out what do about the blower.

I originally started out that i was just gonna refresh the motor and be done with it. Then i was told with a stock 500 i would probably only see 68 to 70 mph that's just not where i was hoping to be.

What do you think about this blower on eBay? I would realy like to get some input on this item below.

http://cgi.ebay.com/ebaymotors/ws/eB...m=140287151756

THe page is not opening when I click on it, but I think the same thing I think about buying any used blower. If you don't know where it is coming from, or itis to good to be true, it probably is.

To me this seems like a good deal but i am not sure.

Here it is again this one works. or item # is 140287151756

http://cgi.ebay.com/ebaymotors/ws/eB...m=140287151756

As long as it is in good shape and doesn't need anything done to it.

That is the old style, but it has an intercooler, so it wil keep the heat down.

I say go for it.

Jeff i just wanted to say Thanks for helping me out it is much appreciated. Is there any specific questions i should ask the seller?

Also griff if you have anything to add feel free, you have been a tremendous help also!

Can I send it back if it is a POS? is the first question that comes to my mind.

Make sure he insures it for you, but the problem is that the freight companies know that these things don't freight very well, so you have a hard time collecting if it comes up damaged, dropped, etc.

You should find out if it is to tall for your engine compartment.

Those things are pretty tall.

The 420 we have just came back from the blower shop, $ 1600.00 plus shipping. :ernaehrung004:

Dean can put you where you want to be .# 216-398-8500 :ernaehrung004:

I wish i had a better idea of what to look for in a blower your price seems good but i would have to have a scoop with the 420 wouldn't i. I think i am pretty limited to what i can buy and it fit under the hatch. I will give dean a call in the morning you are the second person to recommend him.

I am sorry if i am a little hesitant with people on here, its just the guy that sold me the motor was totally full of ****.

I bought the motor from the classifieds on OSO. In no way do i blame this site though only my self for not going to look at the motor before i bought it.

I felt i was better off taking the money and fixing the motor then trying to go after him and waste more money. I am gonna try and f*** his taxes up buy filling a 1099 on the money and maybe the IRS will crawl up his ass.

I just sent you an email also.

I have this setup still

That is sick. What did you end up wanting for it and does it have all the pieces?

I have everything.I want $5250 for it.

That should take that 500HP to 800 pretty easy.:)






Darrell.

Short or tall deck intake?

How many hours are onit?

Yeah, for just long enough to see how fast the boat would go, and then you'd have to call sea tow to get youback.

You could make 800HP out of a V-6 with that thing.

If the Whipple is what he says it is, then its a lot better deal than the TBS 250 set up.

A 502 with a good pair of heads and a 741 cam will make 600 hp by itself. A small supercharger added to that will make at least another 100. I think you could easily exceed your goals with any of these chargers.

AFR 305 CNC'd is a 315. That is the perfect head for what he wants to do.