|
|
![]() |
#1 |
Member
Join Date: Dec 2012
Posts: 227
Likes: 4
Liked 162 Times in 45 Posts
|
![]()
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.
|
![]() |
![]() |
![]() |
#2 |
Veteran Member
Join Date: Mar 2005
Location: Sand Springs, OK
Posts: 8,132
Likes: 896
Liked 390 Times in 170 Posts
|
![]()
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
__________________
Ed Wright 4156 SS/JA Last edited by Ed Wright; 09-30-2017 at 06:49 PM. |
![]() |
![]() |
![]() |
#3 |
Member
Join Date: Oct 2011
Posts: 125
Likes: 47
Liked 21 Times in 9 Posts
|
![]()
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. |
![]() |
![]() |
![]() |
#4 |
Member
Join Date: Sep 2009
Posts: 144
Likes: 80
Liked 88 Times in 43 Posts
|
![]()
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. |
![]() |
![]() |
![]() |
#5 |
Junior Member
Join Date: Aug 2008
Posts: 62
Likes: 4
Liked 15 Times in 2 Posts
|
![]()
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. |
![]() |
![]() |
![]() |
#6 | |
Junior Member
Join Date: Feb 2012
Posts: 62
Likes: 15
Liked 17 Times in 8 Posts
|
![]() Quote:
just sayin... |
|
![]() |
![]() |
![]() |
#7 |
Live Reporter
Join Date: Oct 2004
Location: Hickory, Ky
Posts: 10,685
Likes: 1,994
Liked 11,030 Times in 2,266 Posts
|
![]()
I have a lot to learn before next year, I hope I have enough capacity.
|
![]() |
![]() |
![]() |
#8 |
Live Reporter
Join Date: Jan 2011
Location: New Bern, NC
Posts: 3,467
Likes: 146
Liked 3,363 Times in 731 Posts
|
![]()
I think you're very resourceful Mr Larry you shouldn't have no problem.
__________________
James Williamson W200 J/SA. SS/JA |
![]() |
![]() |
![]() |
#9 |
Veteran Member
Join Date: Mar 2005
Location: Sand Springs, OK
Posts: 8,132
Likes: 896
Liked 390 Times in 170 Posts
|
![]()
Larry, you moving to Pro Stock next year?
__________________
Ed Wright 4156 SS/JA |
![]() |
![]() |
![]() |
#10 |
Live Reporter
Join Date: Oct 2004
Location: Hickory, Ky
Posts: 10,685
Likes: 1,994
Liked 11,030 Times in 2,266 Posts
|
![]()
2015 Drag Pack
|
![]() |
![]() |
![]() |
Thread Tools | |
Display Modes | |
|
|