Setback Blower

Any one useing a setback blower in an alky funny?,and how is it working out?

 

We will be making back to back dyno tests,with setback combinations, on a BAE motor. Setting up today.

 

Mike,
Since the discharge of the PSI Screwcharger is in the rear, you would actually need to set it forward to accomplish the same thing as a set back roots. With the blower belt in the way, this would be very difficult to accomplish. We have looked into it, but don't think the same gains would be there, as it was with the roots. Drazy made the distribution alot better in the screwcharger with the channels and distribution plate on the bottom of his creation.

Take care,
Marty

 

AJ, when you do the tests on the dyno do you have a fan hooked up to simalate the 250. mph wind that the hat incounters going down the track? I know of a supercomp racer that put an air filter in his air scoop, and he picked up 1 tenth and 4 mph. because of turbalance the motor wasen`t getting the air right, i`mthinking that a blower sucks all the air it needs and maybe the wind at 250 mph may mess it up??

 

I think the ihra put a limit on how far you can set back the blower in the alky f/c class , not sure about the pro mods though . I have seen a 16/71 case with 14/71 rotors in it pushed towards the back with a 1" deeper front cover . Not sure if it actually works though .

 

Blower Set Back

As Far As I Know There Is A Rule On Blower Set Back Set By Ihra For Pro Mod As Well As Funny Car. They Include The Cover As Well Because I Know The Snout Can Be No Longer Than 8 In. And I Think The Cover No Thicker Than 2in. May Be Off A Litlle Off On The Mesurements But Close. First They Tried A Snout Limit But That Didn't Work As People Started Doing There Own Front Covers To Get The Set Back. Dques It Sounds Like What You Saw Was A Kobelco Superman But Ssi Is Amking There Version Of The Blower As Well And Davenport Makes A Front Bearing Plate For The Littlefield Blower That Gives The Same Effect As A Superman Design. Typically This Design Works Very Well As It Smooths The Whole Airflow Into The Supercharger And Shimanned Says At 250 Down Track The Ram Effect Becomes Very Importtant As How Eeficent The Air Can Enter The Injector And Flow Into The Supercharger. Some Pro Mod Teams Have Been Doing Some Dynoing And Picked Up 150 Horsepower By Moving The Injector Forward On The Blower. That Is Just On The Dyno As Stated Think Of The Improvment Going Down The Track. Mike Is Also Correct In Thinking The Set Back Manifolds Are Similar To A Four Barrel Intake. When I Was At Force's Shop A Few Years Back They Were The First To Really Run The Set Back Full Time In Fuel And What I Noticed Looking At The Blower Intake On There Funny Car And Looking At The Intake That Was On Ashley's Super Comp Car Sitting Right Next To It The Only Difference I Could See Was One Was Magnesium And The Other Was Alum. Looked Exactly The Same. So Here's More Of An Argument Set Back Blower Or Better Blower Manifold. Tractor Pullers For Years Have Taken Dart Bbc Manifolds And Done Some Fabrication To Adpt. The Supercharger And Have Had Excellnt Results. Possibly The Smaller Plenum Chamber With More Of Port Runners Is A Better Design. From What I Have Seen There Is Not A Huge Power Advantage To Set Back Blowers Just More Equalized Nozzle Jets,cylinders Temps, And On Nitro More Even Compression Ratio's. Out Here On The West Coast There Is A Class Called Aa/gas Kinda Like A Mini Pro Mod Pretty Much All The Same Rules But These Guys Can Only Run A 6-71 Std. Helix At 55 Over. Guys In The Class Have Done The Twelve Inch Set Back Snout As There Is No Limit For Rules On This In There Class As Well As Several Do A Ten Inch Snout Set Back. So Far The Two Fastest Cars In The Class Use The Standard 5in. Snout. Goes Back To Combonation. Tim Wilkerson Put It On His Funny Car And Took It Back Off And As We Know Tim Runs Very Well. Hopefully Aj481x Wil Share His Dyno Results With Us.

 

Ya, Like Bucky Shared his (compression numbers) 10/1 if you want to run unleaded gas,LOL

 

Just a tought, Back in the 60`s there was company ,Rotofaze, that made a blower manifold that had port runners, (nothing new under the sun!)

 

setback rules

The IHRA has just revised their rules for F/C set back. It is now 15" from the front of the pulley to the leading edge of the rotor. Same for ProMod.

We found a 3% increase in our set back manifold over a KB with retro plate.

 

Do Ya Think??

I Have A 14/71 Hi-helix Not A Retro Blower I Am Going To Use A Indy Intake I Want To Set The Blower Back 1.5 Inchs And Move The Hat Foward 4 In Am I Going The Right Way With This Should I Go Back Futher I Havent Put This Together Yet But Very Close. Any Ideas O- Yea 526 Rodeck Dart 360 Heads Thanks Jamie

 

I Have A Enderle Buzzard That A Friend Of Mine Does Sheet Metal Fab He Has Put A Plate In The Back Of The Hat That Has A Roll From The Roof To The Rear Of The Hat More Like A Contour To Remove The Sharp Angle In The Rear Of The Hat It Is The Full Width Just Another Idea To Try I Cant Afford A Carbon Hat Now Just Trying To Improve What I Have The Blower Does Have The Front Opening I Think The Retro The Opening Goes Into The Front Plate If Im Correct I Dont Know If Anyone Has Put A Plate In A Buzzard Before Im Sure Its Been Tried Just Wondering If It Helps Thanks

 

Jamie I Think You Are Going All The Right Ways On Your Hat Smoothing The Air Flow In To The Blower Is The Way To Go And Get Your Car Out To The Track And Have Some Fun Before Worrying About The Carbon Hat Many People Spend There Money In Spots That Aren't Needed In The Begining Before Having Some Fun With There Hot Rod. Hooters Was The 3% Increase In Boost Or In Hp.

 

I wonder if a real powerful leaf blower would put out enough mph air to make a differance on a dyno???

 

RBS

That was 3% in HP

 

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Mike When You Say As Close To The Rotors As You Can Get Are You Talking Thousands Of A Inch Or 1/8 Of A Inch I Might Try This If You Think It Works And The Guy Is Still Working On It Thanks Jamie