My son and I rebuilt his 2.3t short block(86 svo). My machine shop ordered a set of 5.7 rods and Wiseco slugs . Did I make a mistake? Its a daily/weekend track car. Down pipe , no cat 3"ex ,k&n ,ranger roller with a stock turbo. I ask this question because the original engine felt more powerful @14psi (no dyno). I set the timing @14deg plugged spout in and it was a pig. I added 2deg's 3 times (20base) before it woke up. This is my 5th 2.3t, I've been on and off with these cars starting in 1999. Did the nitrous thing, high boost,low boost hell no boost for that matter, I know these cars well enough(cam timing etc.) but I'm stumped. Thanks in advance, Dennis
Well, the first thing I'd want to verify is that the rods and pistons are the correct parts for a turbo application. I've seen a ton of machine shops order hypereutectic pistons, or use circle track style rods and/or pistons since that's what they are used to using. Do you have the part numbers for the rods and pistons?
With that said, if the spout is advancing timing like it should, and the engine is timed correctly, 20 degrees base will blow up the engine or at minimum kill the headgasket in a matter of seconds. So the fact that it didn't kill it means something isn't right in that regard.
Crower Sportsman rods are fine. Mini stock dirt track lightweight pistons are an unfortunate choice. They are weaker than stock since they are made to be used with non-turbo engines spinning 9000rpm so the priority is on being light, not strong.
With that said, that's not the reason it's running bad, it just means you can't push it as hard as you could a stock turbo engine and that it's higher compression so it will need less timing, and you have to run less boost on pump gas than you could with lower (stock) compression.
That's not the response I was hoping for. If my is son anything like me the Pistons will soon find there way to the oil pan LOL. We can do it again and do it correctly. What do you suggest? It is a daily/weekend track car(road course auto cross) . Thanks again for all your help. Dennis
Well, the proper pistons are no longer available off the shelf from "typical" suppliers like SPEEDPRO, TRW, etc. So the proper options are all custom pieces. We sell/stock CP Pistons that are a direct replacement for the stock pistons (only oversize and stronger/better) but unfortunately you can't use those with 5.7 rods. It's not a huge deal as we can have pistons made for your rods, it just costs about $100 more than our "standard" pistons for a stock length rod since we have to buy a single set, not in bulk like our standard pistons. The custom pistons are ~$660 since the 5.7 rods are so long the pin runs into the oil ring so you have to run ring supports which add about $20 to the price. That price includes rings, pins, clips, etc., unlike other pistons.