View Single Post
JBL930 JBL930 is offline
JBL930's Avatar
Join Date: May 2006
Location: UK
Posts: 1,172
Originally Posted by SAY - 642 View Post
Jonathan...your twin turbo is awesome. Did you have to rebuild the engine after your purchase. I read the turbos were shot.

If you had to do it all over again (the twin turbo conversion), would you do anything different?

I have to pick up this issue


Cheers Caesar, don't really want to hijack the thread, but the plain answer would be that it was a long learning curve, even when paying other professionals to do the work!

The 993 turbo that the engine came out of had been in a shunt, which ruined the exhaust system and one of the turbos. At that point i should have simply swallowed hard and bought the 520ps RS Tuning kit, but it's hellish expensive as it's a proper, engine dyno tested and proven package built by the best in the business. With RS you really do get what you pay for!!
Little did i know that the engine originally had that package fitted before i bought it, so the right cams were in there, and the turbos, even though broken were the mega bucks K24/26's..... I had thrown them in my company skip, luckily it's a huge skip and only gets emptied once a year, so when i found out i dug them out, sent them off to be repaired and rebuilt....

I had opted to use local 'mappers' and got ripped off, 'again'....... Long story..... Couple of pairs of smaller K16/24 turbos used....
Anyway, point being is i would not mess about if i had my time over again. I also wouldn't try and mate a 930 4 speed to the 993 engine, it didn't really work well as the starter motor doesn't line up and you have to compromise. With the G50 it's awesome.

Car is now running better than it ever has done, engine has recently been rebuilt with Arrow rods and ARP studs etc...It's perfect off boost, starts instantaneously, drives beautifully, and the boost is completely managed by the Motronic ECU so i have all of the stock 993 turbo safety features, knock control etc, and if there is an issue 'limp mode' will only give 0.5bar as it does with a stock car. Other than mechanical failure the engine is now truly bullet proof. RS say on a fresh engine this package will give complete reliability for 50k + miles, and that would be using it on the German Autobahns.... Just a shame i didn't have the ECU when the magazine article was done.

To the original poster, i don't know a great deal about using NA motronic on a turbo engine, but if it can at least be used for all of the 'off boost' stuff, warm up, idle, cruise.... And then someone knows how to add enrichment for WOT, then i would say Motronic is the tits. It's just a pity that very few people in the world can really map it properly..... I know there are plenty of people on here who have turbo'd their carrera, so those would be the ones to ask
87 930, 993 turbo engine, RS Tuning 520PS/515lbf-ft, Arrow Rods, ARP hardware, Solid lifters, G50-50, RS Flywheel, 890nm Sachs clutch, RSR coil overs all round, 993 C4 calipers front, 930 fronts on the rear, Ruf Speedlines.....
Old 540 BMW, XB12S Modified, for being a total hooligan
Old 07-06-2011, 04:34 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #18 (permalink)