Any tips to stop engine running lean with 4l whipple?


BlackICE

GT Owner
Nov 2, 2005
1,416
SF Bay Area in California
Its actually true, we found out on the dyno last week! we put a vacum gauge on the inlet and saw it drawing a vacum, I cut two holes in the bottom of the air box and the car picked up quite a bit, so now I will be making my own custom air box as well.

What did the gauge read? What type of air filter were you using and did you ever measure the drop across the MAF?
 

D one

FORD GT OWNER - PHILLIPINES
May 17, 2007
49
Good day Gentlemen, Posted my Dyno Graph here, Thanks ! http://s1219.photobucket.com/albums/dd438/gono1/
 

soroush

Ford Gt Owner
Mark II Lifetime
Aug 8, 2007
5,256
What did the gauge read? What type of air filter were you using and did you ever measure the drop across the MAF?

there was a little draw on the gauge read not sure exactly what it was, so we took the filters out completely and made another pass, same thing, still a draw on the empty box, the restriction is the box not the filters. it was already getting too late at that point, we had already battled the car for four hrs and still had not made a pass with the nos, so the car made 750ish then when we cut the box open and spray'd it a 150 shot it made 945. I guess we should have made a pass of the bottle, but again it was late and we needed to make sure the car was ready on the spray.
 

Howard

GT Owner
Mark IV Lifetime
Apr 26, 2007
1,149
Florida/North Jersey
Doesn't the air box have to show a vacuum to draw air in?

Howard
 

nota4re

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Feb 15, 2006
4,281
Just for reference, we are using the OEM airbox for the Heffner TT's that we have installed and tested and each of them are producing 1000-1100 RWHP and ~950 RWTQ. Stock airbox and K&N Filters which are part of the kit price.
 
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paul b

GT Owner
Nov 2, 2006
810
Doesn't the air box have to show a vacuum to draw air in?

Howard

I would say the engine supplies all the vacuum, everything else is at atmospheric. I always thought the air intake was a bottleneck, either the airbox or the size of the inlets. The fact that the intake bellows would collapse should be an indicator.
 

Fubar

Totally ****** Up
Mark II Lifetime
Le Mans 2010 Supporter
Aug 2, 2006
3,979
Dallas, TX
My research netted similar results. Inspire of the relatively small filter surface area, the restriction seemed to be with the intake air passageways not the filters. Any updates on the success of the GTGuys intake system?
 

B.M.F.

GT Owner
Mark II Lifetime
Jan 29, 2009
1,810
Minnesota
Just for reference, we are using the OEM airbox for the Heffner TT's that we have installed and tested and each of them are producing 1000-1100 RWHP and ~950 RWTQ. Stock airbox and K&N Filters which are part of the kit price.

Turbos require much less air than a twin screw or a centrifical blower. Twin screws need the biggest air filter/intake system you can get... Turbo's don't need to flow as much cfm as a blower to make x amount of hp due to the fact that they don't need the drive power to turn them. A whipple like Soroush's or a blower like mine flows more air than a 106 single turbo. But they also rob upwards of 200-250 hp to turn them. That hp is the xtra cfm needed to drive them. Twin screws are the most picky when it comes to airflow to the blower.
 

MTV8

GT Owner
Mark II Lifetime
Jul 24, 2010
1,021
Houston Texas
Any updates on the success of the GTGuys intake system?

I was going to ask the same question. Always found it interesting that so many stick with the factory air box on otherwise highly modified setups.
 

thegtguy

*Supporting Vendor* GT Owner
Apr 20, 2006
552
MI
GTG Cold air kit

My research netted similar results. Inspire of the relatively small filter surface area, the restriction seemed to be with the intake air passageways not the filters. Any updates on the success of the GTGuys intake system?

Thanks Fubar. I was beginning to think that our kit was forgotten about. The first bach of production kits (all spoken for) is scheduled to be complete next week. We have 4 cars here and waiting, all scheduled for dyno time as soon as they are completed so stay tuned. We are hoping to see an additional 50rwhp and hoping for more. On one of the cars we put a list of mods on it including a 4.0l Whipple at 19psi it made 780rwhp with a baseline tune so we shall how much it improves.


http://www.fordgtforum.com/forums/s...ir-induction-kit-by-The-GT-Guy-LLC&highlight=
 

nota4re

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Feb 15, 2006
4,281
Turbos require much less air than a twin screw or a centrifical blower. Twin screws need the biggest air filter/intake system you can get... Turbo's don't need to flow as much cfm as a blower to make x amount of hp due to the fact that they don't need the drive power to turn them. A whipple like Soroush's or a blower like mine flows more air than a 106 single turbo. But they also rob upwards of 200-250 hp to turn them. That hp is the xtra cfm needed to drive them. Twin screws are the most picky when it comes to airflow to the blower.

That makes perfect sense, BMF, thanks!
 

D one

FORD GT OWNER - PHILLIPINES
May 17, 2007
49
Turbos require much less air than a twin screw or a centrifical blower. Twin screws need the biggest air filter/intake system you can get... Turbo's don't need to flow as much cfm as a blower to make x amount of hp due to the fact that they don't need the drive power to turn them. A whipple like Soroush's or a blower like mine flows more air than a 106 single turbo. But they also rob upwards of 200-250 hp to turn them. That hp is the xtra cfm needed to drive them. Twin screws are the most picky when it comes to airflow to the blower.
I agree with BMF. Twin screw needs more boost to develop more power. Unlike the twin turbo setup, an engine making 1000whp might need on 18 lbs of boost on Ford GT motor.
 

Fubar

Totally ****** Up
Mark II Lifetime
Le Mans 2010 Supporter
Aug 2, 2006
3,979
Dallas, TX
Turbos require much less air than a twin screw or a centrifical blower. Twin screws need the biggest air filter/intake system you can get... Turbo's don't need to flow as much cfm as a blower to make x amount of hp due to the fact that they don't need the drive power to turn them. A whipple like Soroush's or a blower like mine flows more air than a 106 single turbo. But they also rob upwards of 200-250 hp to turn them. That hp is the xtra cfm needed to drive them. Twin screws are the most picky when it comes to airflow to the blower.

How is your centrifugal project coming along? Post a link to your website again if you don't mind.
 

B.M.F.

GT Owner
Mark II Lifetime
Jan 29, 2009
1,810
Minnesota
How is your centrifugal project coming along? Post a link to your website again if you don't mind.

It was coming good till I ripped the keyway off the crank just dynoing the car with a stock balencer on the motor. So now im building the built motor for the car. Well motor 1 which will be 358 cubes with a Bryant billet crank and darton sleeves. Then I ordered the crank for the second motor a month ago and its going to be 374 cubes. I will use the same heads just have two different short blocks. So next month im going to work on geting the car painted while I finish the motor stuff. Trying to finish up a couple customers cars and been busy with my composite business so I haven't had alot of time to play with that. But thats all changing towards the end of the month here as things are starting to get finished up.

Hows your car been? Haven't heard much about it lately.
 

B.M.F.

GT Owner
Mark II Lifetime
Jan 29, 2009
1,810
Minnesota
That makes perfect sense, BMF, thanks!

No problem:cheers
 

JAYGT

GT Owner
Nov 20, 2010
175
MIAMI
Can you guys post pics of the modded air box's. I was thinking of making a mold of the factory bottom piece and popping of a fiberglass piece to modify and play with..
 

Fast Freddy

GPS'D 225 MPH
Mark II Lifetime
Aug 5, 2005
2,727
Avondale, Arizona
The most effective advise I have been given on track day temp is to use a higher gear. The GT produces so much torque that it wont significantly affect your times. The lower rpms makes a big difference on engine temps. I hope to have a radiator upgrade by the end of summer.

this is what i do in my Viper on short track road courses. i short shift too when necessary. i have yet to find a motor or trans from Chevy, Dodge and Ford that can keep up with me....

with that said the vette does the best :willy

i can make a set of tires last without getting pissed about it or losing a race. but the fact that water temps and trans synchros don't have what it takes to keep up with me is very frustrating....
 
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Fast Freddy

GPS'D 225 MPH
Mark II Lifetime
Aug 5, 2005
2,727
Avondale, Arizona
Present setup Whipple 4.0 , Whipple Monoblabe Throttle body, Muscle Motorsports 52lbs injectors, NGK TR8 Plugs, Customize intake tube with K&N filter,
Ford Racing Longtube headers, Catless pipes to Accufab X-pipe, Hoosier R6 and 102 Octane Avgas. Stock Fuel Pump, No BAP, Stock Internals reving 7200rpm. Made a Vbox run 60-130mph run, Time 5.3 in single gear. Preparing for 230 mph VBox run.

100 octane low lead Avgas has Manganese and anti-icing agents. it is also oxygenated (runs lean) and designed for low rpm use in which airplanes operate at HIGH altitudes and very cold temps. ditch that gas for a HIGH octane race gas which is made for low altitudes, hot air temps and HIGH rpm's. re-tune your computer and you will make more Horsepower with less detonation and better fuel mileage....
 
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Fast Freddy

GPS'D 225 MPH
Mark II Lifetime
Aug 5, 2005
2,727
Avondale, Arizona
.............................................
 
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Fast Freddy

GPS'D 225 MPH
Mark II Lifetime
Aug 5, 2005
2,727
Avondale, Arizona

i like your air intake setup!!! i wish somebody could do a dyno comparison of this versus stock on the various sized whipple superchargers to see the difference in dyno results.....

you can get a twin Filter-Y that will flow more cfm than that. i used to have one one on an older C5 vette that i used to own. even a blackwing filter would out flow that. batman rules....
 
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