Auto_Werks 3.6

I have a dedicated track car that will do double duty for chump car and autocross. We have a set of coil overs and r comps that we have thrown on it for auto-x but anything we do to the car needs to be quickly reversible to go back to stock for chump. Right now I have a Lindsey boost enhancer and max 951 18psi chip in the car. I set the boost to peak around 16psi in high gears, but in second gear at the autocross it would only hit 13 psi. I know the k26-6 doesn't give a nice flat boost curve, but I would like to get more out of it in second gear. Do I just set the LBE in second gear to peak at 17ish lbs and know that a third gear shift is off limits? Third gear really isn't that necessary as it does 68 in second as is. I'm considering shimming the waste gate, but I'm not sure what would happen when I put the stock chips back in... we can shim the waste gate because it's really low point value for chump, but I'm afraid it will over boost with the stock chips and cycling valve on the track. Can I use an electronic boost controller to get a flatter curve out of the stock gate, or is this just a waste of effort? The car feels unbelievably underpowered with the DOT slicks on it. I might not even mess with it but it's actually not outrageously off the pace of the nationally competitive FP cars.

V2Rocket

take the WG pipe flange gasket, trace on a piece of copper but don't cut a hole in the middle for exhaust flow...

block off the wastegate

Auto_Werks 3.6

Hmmmmm... you say that but I wonder if I put a restriction in front of the gate if it would reduce back pressure on the waste gate valve and give a more stable boost curve. Pick an orifice size that would only let the gate bleed down to something like 14 psi when it's wide open. That #6 hot side back pressure is the real enemy.

Anyone kow if there's a spread sheet to calculate waste gate size that I could abuse for this purpose?

Humboldtgrin

You can work the exhaust ports over on the turbo. Or get this turbo or one like it. https://www.ebay.com/itm/151895592831

CO951

You can shim with stock chips. I had the 26/8, but had shims in my WG and went back to stock chips for some testing with no problems. It should build boost a little quicker, but I wouldn't expect a big change from shims though.
A way out there idea: Would Chump allow any other modifications to the WG? My thought is a while back Blown944 had converted a stock WG to dual port. You could use it as a DP for autoX and SP (just like stock) for Chump.

Johnboy4444

Paging Lart... Supersecret Lartmobile technology is fabled to be the best around...

V2Rocket

Lart's secret to going fast is replacing all the grease and oil in the car with Prime quality LARD
Less friction = accelerate faster, and leave a good smell behind.

Johnboy4444

cam tower can also then double as a sausage griddle...

V2Rocket

Lart put foil on his 951 intake manifold...not for heat reflection, but to warm tortillas without sticking to the engine