Selecting a supercharger
 

I've been researching superchargers for my 598 build and it is very very confusing due to the many combinations available. So I thought I would start a thread to get some dialog started to try and sort it out.

I've talked to every known supercharger builder I can find besides whipple and PSI. A little more than what I want to spend. Thought I would stick with the 71 series.

What sets one builder apart from the rest? Does this depend on application?

Why is it depending on who you talk to some recommend the 8-71 and some the 14-71? If that was all you had to choose was the size. On top of that there are many other things to consider such as; high helix or standard helix, front discharge or regular discharge, two lobe or three lobe, teflon strip or no teflon strip, billet rotors or cast rotors and so on.

I understand it all depends on your specific HP goals, but what is the best bang for the buck?

Every blower place out there who deals with the GMC blowers, has came out with some sort of modification, to make it more effiecient. Thats the ultimate goal. Roots blowers were notorious for being inefficient, and they have developed ways to help it.

Size wise, on a 598, I wouldnt choose a 8-71. I'd probably opt for the 14-71. Its size relative. A 14-71 bolted on a 454, wouldnt really be the way to go, especially on a low boost marine setup. To run a pump gas compatible boost psi, the large blower would be so underdriven, that you get lots of air leakage past the rotors, at their slow speed. In otherwords, less effiecient, less power made.

Same goes for bolting on a 6-71 on a 598. To make acceptable boost psi, the blower will have to be so overdriven, it will create lots of heat. Heat=less power.

Screw blowers are much more effiecient, but do carry a hefty price tag. At the end of the day, its all about how much power your trying to make. If 800-1000HP is your goal, the roots works fine with the 598. If 1400HP is your goal, you might want to look into a big procharger and big intercooler.

On certain 14-71 blowers, you need to watch the case style. Some of them by design, will run hot in either the front, or the rear half. Hard to go wrong with the Blower shop stuff, or BDS. The Billet blowers look pretty sweet too compared to the cast style stuff. With a normal rear offset 14-71, you need a intercooler, or spacer plate to clear the distributor. Or, a offset distributor .

I wouldnt have a problem running a 10-71 on a 598, with a intercooler or meth injection.

So in researching other forums, mainly drag racing forms since they talk a lot more about superchargers this is what I found. Not saying any of this is true because this still seems to be very controversial.

Hi-Helix or Standard Helix
-A hi-helix or 120* rotor is not needed when you are not spinning above 7000 rpms

Cast Rotor or Billet Rotor
- Was told a billet rotor can produce about 100+ more hp than a cast but a cast rotor is lighter so it has the tendency to spin up faster and less wear on the snout and bearings

Teflon or non teflon
-With teflon you can make tighter clearances than with out but there are people out there that say the complete opposite

Front discharge or standard discharge
-The front discharge allows no air reversion due to the air not hit the bottom part of the supercharger and reverting back toward the center of the rotors

This is just some of the info I found. Again some makes perfect sense in theory and some does not at all. I guess that is why you have all the blower builders suggesting something different. In a perfect world I would like to do a back to back comparison on the dyno with all 14-71 combos available.

Jason: A lot depends upon your HP goals and how you intend to run. If you want to make 1000+ HP and run balls out then a Whipple 5.0 is what you want. If you just want to make 800 hp and run it hard only once in a while then a 12-71 or 14-71 will work great.

But you need to match the camshaft and HP goals with the " whole engine packges" . Are you going to go carb or EFI? big difference in cost and what setup to use.

Talk to your engine builder and decide on goals, HP , set up (carb or EFI etc.) and level of boost.

You also need to make sure the boats fuel system will accomadate the increased flow.

Good Luck

Wannabe

Thank for chiming in. Your just down the road from me.

heres a 581ci whipple build that gives you everything but my tuning to make 1100hp,1100tq.

http://forums.boatfreaks.org/showthread.php?t=16735

So what's your issue with prochargers and PSI, Jeff?

They make too much HP.. :evilb:

ya,keep away from psi and m4 procharges,and 8.3Lwhipple,they just dont make power,lol.:party-smiley-004:

Thanks for the info, but not really enough to make an educated decision. I guess what I will do is list every maker of supercharger on a spinning wheel then spin it like I'm playing wheel of fortune and whatever manufacturer the wheel lands on I will order the most expensive one from that manufacturer. LOL! It is very hard to make a decision when everyone claims they make the best supercharger out there and nothing else compares. I do not have the bank roll to start trying them all to see what really is the best.

Yes it can get crazy expensive, I played that game in the late 80s and early 90s, then went back to NA motors Not as fast but cheaper to run.

your right about m4 carbed being a challange,but they make big power on top.

Having the same problem Jason . I put together a pair of 598's and I did a lot of home work on this and my thought is the 8.3 whipple will make between 1100 & 1200 with no problem . Just having a hard time spending 21 K per motor then another 10 K per side to switch out my XR uppers for SCX's . I feel your pain !!!!!!!!!!

Hey Jeff you pretty much hit the nail on the head.

Jason , good vibes racing has a pair of 14-71 hi helix blowers used. Priced right too.

Mike Tkach has a couple 10-71's, and a 16-71 on the shelf he might sell ???

That power level with a 598 should be no problem for a properly spec'd roots deal. Talk to Mark Rinda at M.E.R. He can set you up with everything you need.

We all know the Saying "if you want to play you gotta Pay" never more true then the marine industry, It's like the chain therory what is going to be the weak link in the build? Well Nothing if you have the Cash.

So good luck with your project, hope you get it fiqured out, should be nice when finished.

I think Haxby answered my question, a roots style blower will get me to my HP goals and at a lot less cash. Now just got to iron out the combinations available.

The way I look at it if you are only building let's say a 500 HP engine there is no reason to spend the money on a crank and rods rated for 2500 HP now is there.

I agree most stock internals will handle 800 HP, next the Drives, the props,the drive height, Ign, on and on.
I do wish the best and keep us posted!!

psi Blowers in Stock!
 

We have 4 polished 206b Polished PSI blowers in stock ready to ship. We also have injector hats in stock now. Call 877-bpower-4-u or email [email protected] Thanks

The 4.5L is significantly less than 21k per engine and will easily make 1200hp on a 598ci. We sale 4.5L complete kits with a retail of $16,500 per motor that has every sensor, computer, wire, pump, injector, relays, iac's, tune, dist, coil, belt system, MOAC intercooler and logs, manifold, linkage, SC, fuel fitler/head, fittings.....

For a 598ci, with a roots, you would need a 1471, you should run a billet housing, billet rotor, non-teflon, high helix, front discharge and you'll be close to 1000hp on pump gas. But after you cut the hatch, by the carbs, pumps, reg, ignition, belt system.....

But look at resale, the days of the big belt system, carbs or EFI with carb look, giant scoops are the past. You can make all that power, plus more, under the hatch, with fuel psi, oil psi, oil temp, coolant temp and knock sensing that gets good MPG (for a boat lol) that doesn't need restripped or rebuilt every 3 years, idle at 800rpm with option shift interupt.... Truly no comparison.

I'm not sure this is really true. No other SC company offers complete packages or supporting tunes. Almost none of them offer support on the combo's or the extra parts needed to complete the project.

PSI's really are not for most. They have HORRIBLE distribution, they do not idle without a lot of work. There only good if you know how to set one up, there extremely hard on belts if your making some power, there hard on crank shafts (if you don't have a bryant or similar). If you don't get the right housing/rotor combo, then they are not very good at all. Also, they have 6-9 month lead times, how is the warranty/service after that lead time?

Roots are the cheapest option and do well when the motor is built around the SC. High compression, low boost, big carbs or billet throttle bodies. Proper size sc for engine. But they don't idle well, horrible on fuel economy because so much fuel evaporates while it takes heat away going through the rotors, are extremely tall, belts are typically very loud, most wear and need to be rebuilt.

Dont make power, what are u smoking:party-smiley-004:

i was being sarcastic,i have 8.3L whipples on one of my boats,and love them.

Thank you for the info Dustin. I was just posting the numbers that I was quoted from a west coast dealer at the miami boat show . And yes I agree the EFI whipple set up is a much more efficient set up than a root's deal . When the time is right I will call you .

Jason 3603 Do yourself a favor and buy a 1071 or 1471 from The Blower Shop for around $5500 and have fun. Don't let Whipple charged or anyone else
try to sell you a Whipple you do not want and cannot afford.

Jason, look into Scorpion racing in Livonia. Not far from you and does great work. They have an outstanding resume and their shop is impeccable. Contact Frank McCommas.

The 12-71 is the perfect fit, takes less hp to run and can still make up to 1300 hp

Good Thread Going Here..........:daz:

A high helix 10:71 with the triangulated type discharge might be a good choice. Bds, littlfield, Tbs...all good choices. You might have to be careful on manifolds due to distributor clearance. What compression are you running and do you plan on running a chiller?

It's been a while since I've checked this thread. There has been a lot of interesting postings. I was hoping to get a little more of the facts to what supercharger you select for the engine you are building.

For example you don't buy a Semi truck for a daily driver, it would be a bit pricey and a little over kill. The manufacturers offer stages for thier superchargers. When is a stage 1 sufficient and when is a stage 5 needed?

You may be over thinking this. A wieand 871 (cost effective) could get the job done if you we're on the high side of compression for forced induction. Still a 1071 may be a better choice...spin it slower and make less heat. Add a chiller and you will be spinning the blower faster to make the same amount of boost but shoving in a denser charge. Spinning the blower faster = shorter rebuild intervals. A 1271 would definitely get the job done and at slower speeds but it may have rotor leakage at lower rpm which throttle response could be affected. Not sure what all the stages are but I think a tip stripped high helix 1071 closed off discharge would fit the bill great. Bds, little field, tbs all good choices.

Jason, check ou Dyers. He made me a set for my 575Sci's and everything fit perfect.

http://www.dyersblowers.com/187/index.html

You may want to call DMPE in holland. He deals in TBS and has his own designs of blowers. His website is pretty serious into drag stuff. I'm no expert by any means.

Also check this out...some basics. Page 11 will give you some size data.

http://www.holley.com/data/TechServi...ech%20Info.pdf

1271 Stage 5 Baby! :lolhit: Then double clutch and shift your 5 speed 7 times like Fast and Furious and you will have one sweet ride!

I agree with you Jason, its hard to figure out what to buy when every manufacture says they have the best supercharger, and there is no test data to prove it, just theories.

Seems like the 1071 is a little small (but would work) for you nicely built 598 and the 1471 (but would work) is a little big so IMO the 1271 is perfect. BUT, like you said, what Custom options should it have and why? Sorry don't know the answer to that part.

Here's a link to our 575sci conversions to 871s.

Polished 871s are $3750.00 per engine.

http://www.dyersblowers.com/187/1676.html

Bill Dyer

And thank you for all the great information, knowledge and insight to this thread!

So 1071, 1271, or 1471 ? How do you choose?

And what options done to the blower?

Still a little confused on these