Larry Morgan Interview from Gateway

[jims5600]

I have a question and hope it is ok to post here. I watched coverage from St. Louis at NHRA.com fri. night. Larry Morgan was interviewed and he mentioned that he is having issues with doing burnouts with a FI engine.
He said he had thousands of burnouts in carbed engines and never had a
problem. How different is it to do a burnout with a injected engine?
I must be missing something in not understanding on how injection
would change doing the way a burnout is done.
Thanks
Jimmy

[Ed Wright]

Have to be his ECU tuning. Should be able to do anything carburetors will do, only smoother. Maybe not run quite as fast.

[Rich Biebel]

If your fuel map is off you will have a problem......Been there, done that....

I changed my fuel mapping once by percentage and could not even spin the tires to do a burnout. In spite of my changes my car made that run without any problem......5% change was all it took....EFI is not a carburetor...and it can really make your day go poorly if you don't know what our doing....

Larry need's a tuner to fix his stuff....

[Painter]

The problem is the engine vacuum on the huge throttle blade. Apparently the single blade in the throttle body makes the engine vacuum much harder to overcome than the eight throttle blades with two carburerors.

[Ed Wright]

I have heard them mention it being more difficult to control the throttle, due to the huge throttle blade. May be what he was talking about. Surely they can get the fuel map right.
It would be a different area of the map than @ WOT.
I remember Mike Edwards telling me how awkward burn outs were with that one big throttle blade. Makes you wonder why that big single blade is what they use. If they had used two 4barrel throttle bodies on the old manifolds, they could have just added injector bungs. But, they would still need (smaller) hood scoops. Would not want that. LOL

[jims5600]

Thanks to all for your replies. Never thought about his "computer tune"
being that far off? It would seem to me,racing a pro car that he would
have found someone to correct that condition. Perhaps it isn't as
simple as that? I recall years ago that a IHRA racer,Harold Martin,had
vast knowledge of efi tuning. If my memory is right,I think he was a
pioneer engineer for GM on efi. Just thinking.

[Tom Broome]

That big oval throttle blade was just one of the "spec" parts required with the Holley fuel injection.
NHRA made the deal before anybody got to test the system.
Imagine what the MAP sensor sees as that thing begins to open.
I expect that without the spec parts we would have eventually seen those engines without any throttle body at all. Like the Fiat Multi-Air engine.

[BOB KIRKBRIDE]

The reason Greg Anderson and Jason Line figured it out way ahead of the rest of the Pro Stock racers was the design of the intake runners. Like it was mentioned before if two four barrel throttle bodies were on top everyone would have been running real close from the get go. When they first ran fuel injection at the Winternationals, I noticed that the runners were covered up and the rules originally prohibited that. Chris McGaha tole me that the Summit guys told NHRA that they would load up their stuff before they would show what they had spent hundreds of hours researching with Hogan manifolds.
The other great asset they have is Bo Butner. He has a lot of experience with computer controlled fuel injection. This combination caused fits to the other racers although now most have them have pretty well caught up, especially the Grays. The first time I saw pictures of what they were going to have to use, I knew it would take some time to figure out how to evenly distribute the air to all the cylinders at the high RPM and extreme cam timing and compression these engines have. It works fine on a Mustang and a Camero but Pro Stock is a whole new animal. At Pomona this year Chris McGaha said he still was having trouble with cylinder 8 getting it even with the other 7.

[l88427]

Originally Posted by Ed Wright

I have heard them mention it being more difficult to control the throttle, due to the huge throttle blade. May be what he was talking about. Surely they can get the fuel map right.
It would be a different area of the map than @ WOT.
I remember Mike Edwards telling me how awkward burn outs were with that one big throttle blade. Makes you wonder why that big single blade is what they use. If they had used two 4barrel throttle bodies on the old manifolds, they could have just added injector bungs. But, they would still need (smaller) hood scoops. Would not want that. LOL

Im thinking that the air pressure equalizes quickly on both sides of that throttle blade if its opened too quickly and the MAP being at full pin rich is still not enough fuel to compensate,unlike the accelerator pumps and the venturies that speed up the air on a carburetor,mabe they need a two port style throttle body like some OE applications with a venturi style opening to keep the air speed up as the throttle blade opens?
just sayin...

[Larry Hill]

I have a lot to learn before next year, I hope I have enough capacity.