ramius665

I was seeing boost on my 86 951 w/K26/6, Tial 38mm and test pipe at about 2200 RPM and full boost by 2600. I swapped to a K26/8 because boost was falling off above 5500.

Either way it sounds like your turbo may be failing. If you like quick spool, why not get your K26/6 rebuilt?

951rook

With the difference in lag being minimal, I figured I would replace the 26/6 with a turbo tht has a little more potential for any future upgrades. I look forward to the new addition.

CyCloNe!

Sweet I've been waiting for that lol... figures the one time I'm not stalking him I miss the good stuff.

User 52121

I don't think I saw anyone address this.

While full boost by 4800 is slow enough to raise eyebrows (and see you're getting a rebuild so that's good)... relying solely on the WG spring is going to contribute to slow spool.

I'd definitely look into SOME kind of boost controller.

951rook

Duly noted, thank you for the contribution.

ausgeflippt951

+1 for the boost controller. Definitely need to run one.

Good luck with your decisions; I'd say Pauly D (among others) have basically covered the basics.

You mentioned Vitesse -- i have his St 3 kit and haven't ever had a single problem. Makes great power and is very easy to tune. The Rogue stuff is a bit of a newer fixture to the 951 world and looks really promising though, especially with his new 'standalone-esque' software -- it's more comprehensive than the Vitesse stuff, but is also more expensive.


For your budget-conscious application, I would do the following:

1) install your newly acquired 26/8
2) keep Autothority chips for now
3) install a REAL MBC
4) install a wideband O2 sensor. There are a number of solid brands that don't break the bank.



Then, down the road, upgrade your whole software. Get rid of the AFM and swap in a MAF.

JohnKoaWood

Being that I have worked on and tuned Ramius665's car, I know for a fact he is solely running the WG spring.... full boost (15PSI) recorded at 2600 RPM, still needs to be fine tuned since the new turbo went in, but overall performance didn't change other than to hold 15PSI to rev limiter.

I agree with the recomendation of the boost controller of some sort... even though it isn't absolutely needed (a propper controller will hold the WG closed longer, and alow for fluttering of the WG to optimize the control)..

CyCloNe!

I wouldn't say that Rogue is more expensive, from my understanding Vitesse is 1250 for the kit not including injectors. Where Rogue is 1380-1430 with 80lb injectors, or 1100 with your injectors or 1150 using your injectors and needing a DME conversion.

Both vendors sound like they supply excellent products. I personally deal with Rogue and very happy with my tunes.