Whipple 3300 on BBC

[esenior]

OK...I'm just about at wits end with this project and want to see if anyone else has some advice or insight....

I have a 69 Camaro with a Dart 540 at 8.5:1 compression with Whipple's 3.3L EFI Supercharger. This is a radial setup where the air is pulled in from the back and output through the bottom at the front of the blower. The fuel injectors are also across the back (I believe they call this a wet setup).

Here's the problem...no matter what we do, we can't seem to get enough fuel to cylinders 6 and 8 under cruising load. When the car is on the dyno, and we put her under light load (Boost is only 5-6 pounds out of 12), the 2 header tubes for 6 and 8 start glowing. If we add more fuel, the rest of the cylinders are too rich.

I currently have the car at CCC Motorsports in Santee, CA. They thought it might be the bypass blowing the fuel away, but they tried disabling the bypass and had the same problem. We went ahead and pulled the intake and have shipped it off to The Blower Shop to have it flowed. I'm guessing that the flow bench is going to show we have a flow problem. Am I wrong to think that if we can't increase flow to those 2 cylinders, that we can limit the flow to the other cylinders to try and even things out? Is there something else that could be going on here? They are doing a compression test this week to make sure I don't have a problem with a valve. Any insight or help would be appreciated!

---Eric

[esenior]

Anyone have any advice? I thought someone out there would have had some dealing with a Whipple.

[f-body]

Did you ever find any information on this?

I have looked at the whipple website and they currently have the most bad ass mustang in drag racing. These things are serious.

I spend a lot of time on 454SS.com and they used to have whipple TBI throttle body kits back in 1993 for thier whipple kits for the 454 and the small block trucks.


Please dont get offended by this cause your setup it very serious and has the potential to make great power, but even with the injectors mounted on the back of the whipple supercharger its basically just like the old TBI setup with more injectors. I dont know if anyone on the 454SS.com board had any fuel distributions problems with the older kits that used the TBI setup. The old kits used a stock manifold and the supercharger bolted to an adapter and that was it. Any fuel distribution problems would have been a result of the manifold design.

I dont know how the manifold in your application is, I can see the picture but if its a big box underneath the blower outlet it might be an intake issue.

http://whipplesuperchargers.com/product.asp?ProdID=1173
whipple does offer a W305 series that will bolt onto a 6-71 roots blower intake manifold thast might be the less expensive alternative.

Two areas of intrest. If fuel is introduced before the supercharger it provides a cooling effect before the fuel air mixture is compressed. Then again if fuel was introduced after the supercharger into the intake manifold in the runner just before it goes into the cylinder head like in a true multiport efi setup you might not have a fuel distribution problem. Air follows the path of least resitance, if you are just pushing air into and engine then there is not a fuel distribution problem. All this is relevant to my future combination since I want a big block with whipple on my truck eventually sort of my 454SS clone. Ive thought about this to, but no one makes a multiport intake manifold you could bolt a whipple onto. Or you could take a roots blower intake manifold and modify it for 8 injectors and use a whipple w305 blower. Just some ideas


Please let us know what you found out.

[HATEDc10]

Did you ever find your answer? To me it looks like your intake isn't distributing the air evenly I have a similar build

[andrewb70]

You can use the Holley Dominator ECU which has individual cylinder fuel and spark trim.

Andrew

[Rolling_Thunder]

your best bet would obviously be ditching the wet EFI set up and mounting individual fuel injectors in each port - this way a decent EFI controller can manage each cylinder's needs