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MandMVG
08-19-2001, 03:53 AM
Hi all i just bought a '95 Ultra 21' w a Dominator pump and a 454 Mag. I would like to get your advice as to what kind of blower to look into. Boat runs great i just want a little extra for , well you know. Thanks , and looking forward to getting some help.
Also i live in the Fontana/ Ontario Ca. area so any dealer info and installer info would also be appreciated

Heatseeker
08-19-2001, 06:07 AM
I bought a BDS set up from Good Vibrations Racing (8858 Painter Ave, Suite E,Whittier, CA 90602 800/576-7661 dragparts.com.)
They make a nice blower. Price was $3k out the door. I've yet to install it as I'm putting together a (454)bullet-proof lower end on the advice of the guys on this board.
In the mean time, it looks real pretty on the work bench!!!

superdave013
08-19-2001, 06:55 AM
Heatseeker, I have bought lots of parts from G.V.R. Jim is a very cool guy.
MandMVG, You might want to contact George @ Clay Smith Cams @ 714- 523-0530. He is not the cheepest guy out there but your piece will be set up correct and last a long time. (i.e. cheeper in the long run) He has done many race engines for me and set up my river engine too.
Also you might want to look into GT marine in Montclar (sp?). Gary @ GT buils lots of ski race engines and some pretty wild offshore stuff.

Heatseeker
08-19-2001, 07:33 PM
SuperDave,I've had a lot of luck with GVR also. Jim and Travis have been very helpful.

rivercrazy
08-20-2001, 07:31 AM
Make sure you pump is set up correctly for the higher HP or you won't realize the potential your increased HP gives you.

BLOWNDRAGBOAT
08-20-2001, 03:06 PM
Hey MnM.....HEy kool name. Anyway, Bds,Mike Kuhl,littelfield Ect...Theres a ton of good blower setups out there. If you want the closest thing to a bolt-on without going into the motor then B&M 420 Megablowers work extremely well and are the closest thing to a bolt-on roots style blower you can get. They are designed to be a bolt on for mercury engines. If fact B&M (Holley) supplies this exact blower(MARINE VERSION)to mercury for the SC series engine. They have a specific setup for your motor and how much boost you should run to avoid detonation. I think it's 5-7 pounds on that particular motor. They will also have the proper accessories available to make it as easy as possible. They have a serpentine belt for closed engine hatches and a popoff setup with a 3inch gilmer style belt for open hatches. I have run both B&M (I JUST HAPPEN TO HAVE A COMPLETE UNIT FOR SALE) and BDS. Both have their pro's and con's. I am currently setting up a 14:71 Kobelco Screw type blower on alky. Let me know if you need more help. You can give me a call at my shop if you like. BLOWNDRAGBOAT@YAHOO.COM
PEACE!!!!

ponponracing
08-20-2001, 03:22 PM
Blowndragboat is right. All you will need is 5-7 pds boost and the simpliest blower kit comes probably from B&M. Their serpentine belt gives a very good backfire protection and for that kind of boost it works pretty good. They also have a choice of pulleys if you want to adjust boost numbers. Just try to stick to a 8-71 if available.
If you would like a lot more boost then I would recommend something different but that's a different story.

MandMVG
08-22-2001, 10:38 PM
Thanks to everyone who replied to my post. Blown i may be e mailing you re: the unit you have for sale. Thanks again everyone it's much appreciated

DetroitJim
08-24-2001, 05:47 AM
I'm getting good results from a Mike Kuhl 8-71. The blower is all hard anodized and polished, with a delta shaped outlet repositioned to the forward edge of the rotors. With a standard helix and no teflon strips, it makes about 6-7 lbs on a 454 from 5000 to 6000. I have seen over 10 lbs. boost at 7000 rpm. Actually, my passenger was watching the gage because we were cranking about 95-100 mph.
Good luck and don't forget to get a FUEL PRESSURE GAGE!!!!!!!
DetroitJim

2fast4you
08-27-2001, 06:25 PM
mvg, i have b%m 420 in 21 ft carrera, but i wouldnt just bolt it in stock motor as dragboat says. id bullet proof my motor 1st, less you want to be taking it apart all the time. im running 90 @ 4 1/2 lbs boost with merlin heads, lightnings, malllory, 2 750s by nickerson and strong valves and valve springs, but you do what you think is best . good luck.

BLOWNDRAGBOAT
08-28-2001, 03:31 PM
It appears that 2fast4u knows more than me AND HOLLEY. Based on the information given which is a mercruiser engine, the B&M 420 megablower IS the best blower he can bolt on and get better performance. If you read a little closer, I also advised him to keep the boost down around 5 pounds. This of course is WIDEOPEN boost. Holley also RECOMMENDS this blower and has certain perameters to stay with in or your correct, he will have total meltdown. I am reading the latest bullitin and it clearly states for his engine that 5 pounds is safe on pump gas. I have set up several variations on my customers boats at 7 pounds with a superchiller and 30 degrees total advance which keeps it safe and not detonating. I will gladly fax it to you if you wish. But what do I know, I only build racing engines WITH WARRENTY for a living.

BLOWNDRAGBOAT
08-28-2001, 03:47 PM
Originally posted by BLOWNDRAGBOAT:
It appears that 2fast4u knows more than me AND HOLLEY. Based on the information given, which is a mercruiser magnum engine, the B&M 420 megablower IS the best blower he can bolt on and get better performance. This motor has big rods,4 bolt mains and rectangle port heads as well as an 8.5:1 forged flat top piston. I didn't go into detail on this forum and offered to give my shop number so I could tell him everything else he needs to do to maximize his performance. Things in particular such as a carbs, blower cam grind and ignition upgrades. As far as heads. I see so many people go overboard with head selection for just 5-7 pounds of boost. His heads are fine as long as he keeps his boost down to the recommended level. Anything over that and of course I would buy a set of aluminum heads with a focus on the exhaust valve area. If you read a little closer, I also advised him to keep the boost down around 5 pounds. This of course is WIDEOPEN boost. Holley also RECOMMENDS this blower and has certain parameters to stay with in or your correct, he will have total meltdown. I am reading the latest bullitin and it clearly states for his engine that 5 pounds is safe on pump gas. I have set up several variations on my customers boats at 7 pounds with a superchiller and 30 degrees total advance which keeps it safe and not detonating. If he was gonna tear the motor down and build a SPECIFIC blower motor than of course I would give him a completely different setup to suppport a typical 8:71 blower such as the ones I use from Mike Kuhl. I will gladly fax Holleys tech info so you can check it out yourself if you wish. But what do I know, I only build racing engines WITH A WARRENTY for a living.

MrHavasuCat
09-04-2001, 01:15 PM
Blowndragboat,
The merc 900 sc's run a Mooneyham blower, and the 575's I believe run a Wiend (sp).

driveless
09-04-2001, 11:21 PM
All this talk and no mention of a Whipple? A screw compressor is far superior to any roots style or vortec/paxton(centrifugal?) type compressor.
-driveless

driveless
09-04-2001, 11:27 PM
BlownDragBoat- what exactly is a 14:71 Kobelco screw type blower? Are they making a screw type supercharger similiar to a PSI or Whipple?
-driveless

BLOWNDRAGBOAT
09-08-2001, 04:10 PM
Hey Havasu...I stand corrected on the 900sc. They are using,so Iam told, 2 versions now one of them is the littlefield and the other is the mooneyham. The 575 is using an 8:71 weiand unit. When I made my statement I was thinking about the 600SC particularly that uses the Big B&M. My point was that for 5 pounds, the B&M is a perfect unit to bolt on to a mercruiser 454 magnum motor as far as a roots style blower goes. I guess I shoulda been more clear. Thanks for pointing out my error. The post was in response to MVG and his question as far as a bolt on deal. One reply stated that he needed to BULLITPROOF his motor which I disagree with AS LONG AS HE DIDN'T EXCEED 5 POUNDS of boost. Obviously, he would also need to change cams, upgrade his fuel system as well as set up a pair of blower carb and recurve his ignition for a blower application. Anything OVER 5-7 pounds of boost would require a specificly built blower motor but than of course I would recommend the BDS,KUHL or Wieand 8:71 deal. Sometimes when your trying to do this online your thoughts sometimes don't get in your post just the way you intended...OH WELL just trying to help.
[This message has been edited by BLOWNDRAGBOAT (edited September 08, 2001).]

BLOWNDRAGBOAT
09-08-2001, 04:24 PM
Driveless......The Kobelco I am referring to is a 14:71. It's for racing applications that run alcohol or nitro. My current motor uses this blower and runs on alcohol.

ponponracing
09-08-2001, 07:42 PM
Driveless, I spoke with Paul Pfaff about that Whipple, and he told me the Whipple being sold is too small. A bigger version was being worked on but they droped it. But the principle is very good.

2fast4you
09-18-2001, 06:04 PM
hey blowndragboat, geez i wasnt saying anything against your knowledge at all. I was just saying id never just drop a blower on my motor without going thru it regardless. just my 2 cents but only makes sense to go thru motor . I dont know anyone who puts on sc and just cruises and i only want to tear that motor apart 1 time. your advice and opiniona are highly regarded. my motor was built per Bob Enders personal specs, im sure you know him,, and he never said just throw the blower on and go.

ponponracing
09-18-2001, 06:39 PM
He 2fast4 you, get rid of the Mallory and you will gain power, take it or leave it.

BLOWNDRAGBOAT
09-18-2001, 07:08 PM
My Bad 2Fast...I actually forgot about it till now....I looked at the date and also remembered why I was such an asshole that day. We just finished a customers motor and was getting ready to install it when the overhead crane cable BROKE while the engine was about 7 feet in the air. The boat was a 27ft Fountain. Luckily, the motor missed the boat but landed hard. Now here Iam STARING at a brand new 540 blower motor laying there on the F**kin floor. Crushed oil pan, broken oil pump shaft, broken GIL stainless steel offshore exhaust manifold, Broke off a drive pulley. Pretty expensive day. So to say I was slightly pissed off was an understatement. I figure that little problem cost me about 5 grand not to mention having to explain it to my customer. Luckily, I found out today that the crane company that installed it never load tested it so THEY offered to pay the total bill including my extra labor!!!!! How kool is that? Anyway, I owe you a BIG beer. Sorry for being a dick.

2fast4you
09-18-2001, 07:58 PM
pon pon i dont like messing with succes. my mallory has given me yrs of use and 90 is about all this 20.5 boat will take with that arneson on it b4 getting really scary. peole have told me they can see all the way under my boat in small choppy water and yu have to really steer it. hopefully this motor will be going into a cat that can take the hp and then the mallory may be gone, but its working ok. thanks

2fast4you
09-18-2001, 08:01 PM
hey dragboat no problem bud, sounds like you had a shitty day all right, been there. instead of the beer how about your suggestion on best way to change oil in blower? do you take them off or is there another trick? as always your suggestions are appreciated, oh how big of a beer??? lol

racingrascal
09-18-2001, 09:37 PM
Question for the blower guys, what is the difference between a 8:71 and 10:71?? My motor that is being built for my boat is almost done and at the last minute I am thinking of putting a polished blower on it instead of the tunnel ram that was going on it. Any ideas? I only have a couple of days to figure this out? Thanks in advance guys.
Andy

boatnam2
09-18-2001, 09:52 PM
hey rr,let me know if you decide to go with a blower my buddie works at littlefield.i think he even has a couple of 1071 for sale and there new.man make sure that's want you want to do though cause a blower is hard on the parts and don't let anyone tell you any different.i mean really a tunnel ram dosen't cost nothing so why dont you give that a try and see how you like it and you could always add the blower later.since you already will have the carbs.but the dealio on the blower is the bigger the better turn the blower less make just as much boost and its a lot better on your motor.i would of put a 1471 on my last boat but it wouldn't clear the back of the boat.if incase you just have to have the big unit e mail me i bet i can get you a real nice deal and the guys in your hood.south bellflower.

ponponracing
09-19-2001, 06:47 PM
A 10-71 is simply longer than a 8-71. Of course it may give more boost if needed, but the main difference for a performance engine builder is that if the motor is built with a 10-71, the extra blower lenght makes it difficult to fit the distributor assembly in the stock location. Means extra money for customer.

racingrascal
09-19-2001, 08:14 PM
Thanks, I am only looking to run about 5 pounds of boost. I think an 871 will to the trick. Any other thoughts let me know.
Andy

froggystyle
09-19-2001, 10:40 PM
I can't believe no one is mentioning the extra key you most certainly should run with a blower. Pon Pon? BlownDB? Where are you guys on this one?
What I am getting at is that the front nose of your crank is subject to much more load when you run a blower. To the tune of 40% of your actual crank horsepower. Meaning, If you are making 1000 hp, your blower would be requiring 400 hp to turn at full boost. (I'm pretty sure this means you would get 1400 hp if the blower magically turned itself) This formula I believe is true for 10#. I don't know about lower boost. Bottom line is, to compensate for this extra load, blower hubs have an extra 1/4" keyway milled in the hub so you can run two keys, one a larger key opposite the smaller original. Once a blower sneezes and tears that key, you could have a problem.
I also heard you want to make sure you have a forged crank for this same reason. The added stress to the crank nose can cause failure in a casting.
BTW, the crank needs to come out to do this job. BDB, Ponpon, please correct me if I'm full of it.

ponponracing
09-20-2001, 01:53 PM
You're right froggystyle. Blower need double keyway to make sure it does the job. There should be a .0015 to .0020 press fit on your crank snout, that's why most blower motors still run with a single keyway in front. But the real way to go is with 2 keyways.
Of course, blower motor should use a good steel aftermarket harmonic balancer instead of the stock nodular iron one. When you order a crankshaft from the crankshop, you can order double keyway grooves at no extra charge.

BLOWNDRAGBOAT
09-20-2001, 06:18 PM
Ok..LET ME CATCH UP. I have been glued to the TUBE the last few days. Besides that, I just took an order from a guy that HAS to have more money than sence. He just took delivery of a 47ft Apache with triple 500hp's. The boat was in the water one time and he brought it to me and wants me to build him 3 705ci motors for his boat!!!! NO I AM NOT KIDDING. I told him that before I do anything I would require a 50% deposit. This guy says no problem and shows up the next day with a check for 60 grand!!!!! So as you can probably tell.... IVE BEEN BUSY
Ok here we go....2fast, some blowers are easier than others to change the oil in. For instance on the B&M I use a suction pump and pull it out that way if the customer is in a hurry. I PREFER to remove the blower and then remove the end plates. This way I can inspect the rotors and clean the gears. As I said, some are easier than others but if you don't care about inspecting the rotors and gears than just suck the old lube out thru the filler hole. If you want me to explain what you will need just emailme at BLOWNDRAGBOAT@YAHOO.COM THE BEER IS KEG SIZE!!!!!!
RACINRASCAL....Build the motor with blower pistons if you have the chance. I like to use a special 7:1 blower piston. I use this specific piston because I can run more overdrive (BOOST) without detonating. If all you wanna do is run 5 pounds of boost than a B&M 420 megablower or any 8:71 will do just fine. Don't spend the extra money that you won't use. REMEMBER THE FASTER YOU OVERDRIVE THE BLOWER THE MORE IT HEATS UP THE INTAKE CHARGE. INVEST IN A SUPERCHILLER. As far as the differnce's. The numerically higher the blower I.E. 6-8-10-12-14-16:71 the larger the rotors which also requires a longer blower case. Also, the internal differances are airflow per revolution. Example: A 6:71 is around 411 cfm per rotor revolution. A B&M 420 does exactly that..It flows 420 cfm per revolution. Most 8:71's are around 429 cfm. Thats why blowers have to be bigger in physical size. So...your 5 pounds is pretty easy on parts as long as you have the right stuff in the bottom end. If your running 5 pounds and no more than that, it's not nessesary to machine a second keyway in the crankshaft or balancer. After all, you have a popoff valve that will take care of any blower sneeze. If you run anything MORE than 7 pounds of boost than as a PRECAUTION I would go ahead and do it. A forged crank is a must as is forged pistons and good rods. IF your gonna do a head job, don't waste your money on a racing valve job. These type of valve jobs are for naturally aspirated motors. On blower motors it is more inportant to concentrate on the exhaust valve area and port size. Again, I am going off your 5 pounds. I also wouldn't waste alot of money on big nasty heads like I use. I am running MONSTER engines. The smallest I build is a 540. These engines require larger heads and valves. I didn't see what your running for CI so I am guessing its a 502 or less. A good set of rectangle port heads with some exhaust valve work and port matching will be more than enough to support up to 7 pounds. Anything above that then you will need to step up. If you want to get specific on my recommended setup then Email me....I am getting long winded BLOWNDRAGBOAT@YAHOO.COM...PEACE MY BROTHA"S BOTHA"S

rodneyking
09-20-2001, 07:48 PM
m
[This message has been edited by rodneyking (edited September 21, 2001).]

boatnam2
09-20-2001, 07:59 PM
andy, i thougth about it all day and if it was me i would leave the tunnel ram on it.since its already built im sure it dosen't have blower pistons,the block is probaly not o ringed and im sure the compression is high.and i think a 540 with a tunnel will last forever.just my 2 cents.

racingrascal
09-21-2001, 06:18 AM
Blown thanks buddy! It's a 540 cid with Dart Alum. heads. The motor is being built right now, it was going to have a tunnel ram on it but I rode in a blown HTM last weekend and decided at the last minute I might want a blower for the look and sound and the power at high RPM. That's why I didn't want to go with a bunch of boost, something some what easy on the motor plus serve a purpose. The 540 is going to make about 650-700 hp, that's what I was told with no blower. I was thinking with 5 pounds of boost it would make closer to 800, but I don't really know. It will run on pump gas also. Any thing else please let me know what you think, thanks a lot for the help guys!!!
Andy

racingrascal
09-21-2001, 06:23 AM
Boatnam your probably right, but I just want it. I do believe the motor is oringed. But none the less if it isn't the right deal then I am just going to have to wait, I don't want to but the budget is tight.
Andy