JDeitz951

What type of boost controller do you have? You must run the boost and fuel pressure that the chips are designed for or you will not have the correct air fuel ratio (= bad).

NZ951

I dont believe that changing the chip and not boost made that much difference, especially a noticable difference... ditto what Deitz said.

Blitzen

I currently run an APE Stage I chipset with an OE fuel pressure regulator and a Lindsey MBC.

JDeitz951

I believe APE Stage I is intended for stock boost, but I am not sure. The Lindsey MBC - do you mean a LBE? From the factory LBEs are set to stock boost. If you nmean the type with a ****, be sure it is set where you want it. Additional boost with same fuel makes it lean, eats head gasket. If you feel like having the peace of mind of a matched setup I like my Guru 18psi kit (was $300, incl. chips, 3.0 FPR, reliaboost, shims). I hear Vitesse is good, too.

Blitzen

It is a manual boost controller, distributed by Lindsey. When I took off my intake, I got rid of the cycling valve, routed my OAS to a catch can, installed the Lindsey Idle Control Valve hose update (aka venturi delete) and installed the manual boost controller.

So, pardon the ignorance, but what's stock boost? And how much should I run? When it just nudges 2.0 BAR indicated on the dash, this car really scoots.

NZ951

If you can afford it, ditch that LR boost controller, it has a decent reputation of spiking. There is a lot in history about the preferred controllers...

JDeitz951

I think stock is 11.5 psi which is .8 bar. If I were you I would research to find out what the chips are designed for and what others with the same are doing. If you think 14 is nice, try 18 (but not with your current setup). You've made a good start. Next get a real boost gage, 18 psi chips and 3.0 bar FPR. Eliminates the guess work.

JDeitz951

Isn't that the LBE that has that bad rep? I think the Lindsey MBC (not the same as the LBE) is like all the others that are based on commercial air pressure regulators.

Blitzen

What chip would you guys recommend? And do really think 18 lbs of boost is okay on an original, never-been-apart engine with 150k miles? And if so, don't I need to work a proper waste gate into the equation?

Blitzen

To the top - a few unanswered queries. Thanks!

Oh and BTW- ran the car at 2.0 BAR all day today at Lime Rock, and it ran fabulously. Kept up with an '80 Carrera (2,400 lbs) with a Euro 3.6 motor (300 HP), so I think I have enough power :-)

Gotta love track mileage - I think I saw 7 MPG :-))

JDeitz951

2400 lbs + 300 Hp = much faster than your 951 and mine. The driver was defective.

Blitzen

Hmmmm-by my estimates, with 2,900 to carry around, I'd need 360HP to keep up (8 lbs/hp), correct? Perhaps his car was not running right (although I spent a 4 sessions in the right seat, instructing the owner's wife) but it seemed quite strong.Perhaps I was simply coming out of the turns harder :-)

JDeitz951

My estimated showroom hp (that's my pet name for flywheel hp since that's what they advertise for new cars) is 285, so you might say I'm right even with a 350Z for example. But what about torque. Isn't that what gets you down the drag strip? 951s have gobs of torque on boost. My estimated torque is 330 vs 254 for the 350Z! Maybe you out-torqued that 911?

My estimates are based on dyno sheets I've seen for 951s with the same setup as me.

Blitzen

Like they say: Horsepower sells cars, but Torque moves them! FWIW the guy in the 911 was stunned by how fast my car was (frankly, so was I)-when fully boosting, it was virtually impossible to get all the power down on a wet track (3rd gear burnouts can be quite exciting!)

JDeitz951

I'm still wondering about your above-stock boost level with youir stock fuel delivery. It's not a matter of if but when will the head gasket burn through. You know, you can crank it up to 23 and put down 350 hp...for about 1 day. That's my last word on that subject.