Blower Cam Advice and Help!
 

Rebuilding my old 454 (468). Block is being bored .100 over to a 475 cid. Block is a GM Bowtie 4-bolt main, tall deck, have just about all my parts, flat top pistons for 8:1 comp, LA Enterprise Kryptonite crank, Carrillo rods, Reher-Morrison Signature Series CNC Ported Brodix heads with little more custom porting (flowing a tick over 400 cfms), Crane Gold Race full roller rockers, The Blower Shop 10-71 Blower with nylatron and Teflon strips in rotors and The Blower Shop Intercooler, 2 Chuck Nuytten marine prepped blower 1050 dominators carbs, Weaver dry sump oiling system with Weaver pump and tank, MSD 7ML-2 & Pro Power Coil and MSD Marine Distributor, Jesel belt drive, etc. Want to make max horsepower at 5600-5800 RPM. Motor is set up to run solid/mechanical roller. Need advice on specs to be at that 5600-5800 rpm target.

Thanks,
Johnny

Re: Blower Cam Advice and Help!
 

To run on pump gas with about 8 to 10lbs of boost. Underdriving the blower.

Thanks again,
Johnny

Re: Blower Cam Advice and Help!
 

Contact RMbuilder (Bob Madera) he will set you up. He did my cam and I gained 60HP!!

Re: Blower Cam Advice and Help!
 

If someone could recommend a good electric fuel pump for this application, I would appreciate it.

Re: Blower Cam Advice and Help!
 

well, for off the shelf Crane cam you could look at the 138781. Its a 246/254 114 .615/.636 It would be managable (barely) around the dock on a 468 and the lift isn't so extreme that you're looking at valve spring problems.
As far as a fuel pump, Aeromotive or Product Engineering. Aero is a fairly straight forward, easy to use pump, The PE is a little more intense. It is the same design as the Magna pumps, but PE is the original.

DAVE

Re: Blower Cam Advice and Help!
 

Thanks Dave,

Would that cam make peak power below 6000 RPMs? Need to max power out around 5600-5800 RPMs.

Thanks again,
Johnny

Re: Blower Cam Advice and Help!
 

Nice HP gain with cam change only!

Thanks

Re: Blower Cam Advice and Help!
 

A boating buddy of mine told me that Crane Cams Part # 138551 would be a good choice for my 475 ci blower motor with max HP at lower RPMs. It has 238 int./246 exh. @.050 with 0.595 int./0.615 exh. lift. Its on a 112 Lobe Separation, told that was perfect for a blower motor. With a cruise RPM of 3400-3800 RPMs. Grind Number: SR-238/350-2S-12 IG. What do you think?

Re: Blower Cam Advice and Help!
 

for a fuel pump a s-x 18203 will work and is coast guard approved also a 15402 regulator is match to work well.

Re: Blower Cam Advice and Help!
 

Your part selection doesn't make sence to me. All of those high dollar parts and you only want to spin 5600-5800? You could do that with Eagle components, a 8-71 and a couple of 750 holleys. Even with a small cam, this engine will still be a pain to live with on a daily basis. A 600 ci short block is what you need to go with the rest of these parts.

Re: Blower Cam Advice and Help!
 

Well the motor was an A-Class motor in my race boat, which I am converting to a pleasure/poker run boat. The motor was 12.5:1 comp natural aspirated single dominator 850HP @ 7000 RPMs on CAM2. So I already had all those high dollar parts. I don’t want to stroke the motor because I already have that Kryptonite crank and those Carrillo rods. Since the block is a GM Bowtie block with thick walls, I can punch/bore it to a 475 CI, most CI without stroking it. I want to run as much HP as possible at the lowest RPM as possible to save parts, drive, gas, maintenance, etc. all on pump gas. I am on a tight budget now. I do not make the money I use to, needless to say. So I am trying to work with what I already have. Only had to buy pistons, blower, intercooler and one more carb. The rest I already had and they are in like new condition. That is the only reason I am doing it this way, I know the 475 CI is small and an odd number. I wish I could pony up to stroke the motor to a 632 or something. But I have what I have and now I make less then ever before with 2 kids thrown into the mix. Which is why the boat has not touched water in 4 years, but kids are just old enough (daughter 3 and son 2) to fit in life jackets safely and wife gave me the green light and a BUDGET! No questions ask, I ran to the machine shop with what I had, and gave them my budget and goals. This is where I am at, just need cam advise and fuel pump advice… Hopefully soon, Prop advice! But I think Throttle-Up has me covered there!

Re: Blower Cam Advice and Help!
 

Use the crane 138551 or similar. Thats pretty close to what we run with 875 HP on a 510 inch platform and it works great. A whole bunch more cam will be hard on valve train and not make much more power. You have a chiller so let the blower do the work. I reacon you will go pretty close or more than 875 with what you have. I think you are making a mistake boring it 100. If you damage a cylinder you got no more to go and how much extra power over a 60thou bore will you make. Sounds like that engine has been set up by some pretty good nascar guys so 6000 shouldnt be a problem with that cam.
Thats a cool boat. I looked long and hard at it when it was for sale here. Have you bought it or was it always yours. I would love to know how you get on with it. How fast it was and how fast after the rebuild. Send me a PM if you like.
Good luck. Jason Frost

Re: Blower Cam Advice and Help!
 

Hey Jason,

I remember when you were interest in buying my boat. I did have it at Pier 57 and Frankie gave me your email. Frankie did have it posted on here for sale; I emailed you a few times about the boat. I decided to keep it. I did a refi on my house and paid the boat off and got the wife off my back about it lol.
I am in the middle of converting it to a poker run/pleasure boat. Pump gas motor, back seat, stereo etc…
The engine shop sonic checked the block and said it was good for 120 over or more. So we went with a 100 over to a 475, odd number, huh? We have room for a few more rebuilds.
Boat ran around 95mph with the old natural aspirated 850HP CAM2 motor. I am in hopes of being right back there with blower pump gas motor. But from the sound of it, with you using about the same cam as the crane 138551 and your power, I just might get there or a little more...
I told the engine shop to make the engine user friendly, low maintenance, easy on parts. It was the engine shop decision to let the blower do all the work and a friend recommended me to drop the rpm range from 7000 rpms down to a friendlier 5600-5800 rpm. The engine shop agreed. We are just in the middle of researching for the proper cam.

Jason was good to hear from you, I will keep you posted.
Merry Christmas,
Johnny

Re: Blower Cam Advice and Help!
 

You have more cyl head flow than you will ever need for that size engine. Because of that, you can use a short duration cam. That Crane 551 cam seems close, but in my experience it will make peak power at 5600-5800 in a 540 with really good heads. And the blower will push the hp peak higher also.

Re: Blower Cam Advice and Help!
 

you mention eagle components in your post in a fashion that makes them look sub par, i have eagle h beam rods in mine is there something i should be concerened with.....I am about to put it back together know so i would like to know if i am duing something wrong..

Re: Blower Cam Advice and Help!
 

Hi PatriYacht,

What cam would you recommend? We plan to under drive the blower, which will be easier on it and make less heat. Airflow numbers in and out it very good. Just need to find the right cam to keep the rpm power range down. We are trying to keep the duration at or below 240 degrees and the overlap in the range of 112-115 degrees. What do you think about the 112 lobe centers and 238 int/246 exh? What would you recommend to keep the rpm power range in the neighborhood of 5600-5800 rpms with my setup?

Merry Christmas PatriYacht,
Johnny

Re: Blower Cam Advice and Help!
 

Eagle stuff works fine for what most of us do it yourselfers do. You just have to make sure all of the dimensions are correct. Up to about 1000 hp and 6500rpm it seems to hold togetherjust fine. I think Arcticfriends uses Eagle in his blower motor at 950 hp.

Johnny, I think you're going to need something custom because your combination is unusual. I'm using a hyd roller 236/240@ .050 .630 lift in n/a 540's. My heads flow 380int/290 ex at .600 lift. Hp is 700 at 5900 with dyno headers. With a supercharger you would generally add more exhaust duration so now it looks like the 551 cam would be good. However, I think with you're smaller cubes, lower compression and 2 dominators on a huge blower, it is going to be a pain at idle and it will have soggy midrange. Just about the time the blower starts spinning at an efficient speed,you'll be at your max rpm. If you really want to run this big blower and 2 dominators on this small of an engine, I would use a small solid roller about 238/248 maybe on 114 degree center and about .650 lift and plan on 6500 rpm redline. I bet with this combination the hp would keep climbing until valve float set in. Somwhere around 1000 hp at 7000 rpm or so. Good luck and Merry Christmas. Ian

Re: Blower Cam Advice and Help!
 

Staying in the 5800 rpm range, I agree that would be a better choice
That cam starts waking up at 3000 and runs to 6500

DAVE

Re: Blower Cam Advice and Help!
 

Thank guys for your help.

I think we are getting close. PatriYacht, if you or anyone else can think of a custom grind and specs that would be better or even an off the shelf cam that would be better then the Crane Cams Part # 138551. I know my combo is odd and this is why we are having a time finding the best possible cam for my application.

Take a peak at these cams a few have PM me about:

Lunati Part #: 502A1LUN
ErsonCam Part #: E129870
CompCams Part #: 11-694-8
and those 2 Crane Cams Part #: 138551 & 138781

Thanks again and MERRY CHRISTMAS TO ALL!
Johnny

Re: Blower Cam Advice and Help!
 

I would have Cam Motion custom grind something around 630-650 lift and 238- 246 Duration on a 114. With that little engine I would have used a 8:71 blower and 2 -750's. That 14:71 is eating Horsepower that you are trying to gain.

Re: Blower Cam Advice and Help!
 

I have an Aeromotive Fuel Pump, regulator and Peterson Filter with one season on it for sale in the swap section.

Great price for the package.

Re: Blower Cam Advice and Help!
 

Thanks Tyler,
I will pass the info to the maching shop.

We went with the followoing: block is a GM Bow Tie 4-bolt main tall deck-100 over 454 (475CI), will be a fixed/mechanical roller cam, the heads are Reher-Morrison Brodix aluminum CNC ported heads and some additional port work done to the exhaust with a little clean up work done to intake, using Crane Gold racing full roller rockers, oiling system is a Weaver dry sump system with Weaver pump and tank & Mercury Racing SC1000 oil pan, the crank is a LA Enterprise Kryptonite stock 454 length, the rods are Carrillo Rods little longer then stock length (but not stroked) SRP Pistons flat tops at 8 to 1 comp, The Blower Shops 871 with Teflon in the rotors, intake is port matched with Keith Eickert Performance Products intercooler with Cupro-nickel core, 2 Nickerson Performance Marine 980 cfm Blower Comp Carbs recommended by Dean , Fluidampr Harmonic Race Balancer, Jesel belt drive system, Keith Eickert Dual Stage Extreme Raw Water Pump and water crossover setup with 2 Keith Eickert sea strainers, offshore water pickup & out drive pickup, MSD 7ML-2, MSD Pro Power Coil & MSD Marine racing distributor, Presolite alt and Tilton starter, CMI Comp SS big tube headers with 4" w/ dry pipes. Motor is finished and will be dyno'd next week. Wednesday, May 30! Looking to go racing with OPA in 2008. Working on getting some sponors.

Good Luck!:D

That sounds like a wild engine! Wish I had a couple.:D Will you be in St Clair?

Attachment 279818Pics of Aqua-Holic Racing blower motor and link to video of motor on the dyno:http://wallysprecisioninc.com/video/..._aquaholic.mpg