Scott 0 Posted May 14, 2004 If things get bad and I feel I warrant a new bottom end for the VR6.... what would you do? Obviously I am not loaded at this present time so need sensibly priced ideas... I can do alot of the work myself to keep costs down - a little nervous with the timing on a VR6 though :oops: I have thought about getting my local engineering shop to overbore the 2.9 and put in new pistons, etc myself.... How far can you go with the 2.9 engine or am I better off sourcing a 2.8 block and over boring that using my standard pistons? Any suggestions? I know I can get Vince to do the job but I dont have £2.5k spare :cry: Scott. Quote Share this post Link to post Share on other sites
PhatVR6 0 Posted May 14, 2004 Get a knackered 2.8 block, with a good crank, and bore it out for a 3.0 or 3.1. Quote Share this post Link to post Share on other sites
Scott 0 Posted May 14, 2004 Can I not do that with my 2.9 ??? Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted May 14, 2004 Certain crank and piston combos can get you well past 3.1, but it ain't cheap. Scott, if your piston choice necessitates overboring larger than standard bore, then yeah you can rework your 2.9. The 2.8 is needed to get back to 2.9 again as VW don't sell overbore pistons for the 2.9. Personally I'd spend a little extra whilst the engine is out on some decent pistons and a 3.1 overbore. JE pistons are the fellas to use and they even come in 9:1 and 11:1 flavour for high torque naturally aspirated (11:1) or for use with a supercharger (9:1). Another 100,000 + miles of fun with significantly more power! Quote Share this post Link to post Share on other sites
dr_mat 0 Posted May 14, 2004 A lot of people have said that the 3.1 overbore is a little close to the limits, and can be a bit unreliable. Up to you, but if you're going that way it's something to bear in mind. Cheapest fix is definitely to pick up a 2.8 and rebore it to 2.9 and re-use your existing crank/pistons and 2.9 head. Quote Share this post Link to post Share on other sites
Storm 0 Posted May 14, 2004 Kev, do you know why people dont use oversized rings on the 2.9, with standard pistons? Apparentley they are available? Quote Share this post Link to post Share on other sites
Scott 0 Posted May 14, 2004 Probably because you wont be able to fit oversized rings on to the OE pistons on a worn VR6 as they tend to wear ovalised on the bores ....I also think you can only over size the rings by 0.025 max? Cheers for the tips guys... 3.1 sounds great but I reckon am looking on £500 alone for the pistons plus the necessary engineering work.... realistically £1k without labour.... no wonder Vince charges £2200... If the engine needs to come apart for major work then I will be costing up all options - It would be interesting to find out how much bigger I can go on the exisiting 2.9 block with over sized rings.......... could be a good cheap alternative ... Do you think I will need new big / little ends whilst its apart? With 112k on it I cant help wondering if its going to be cheaper just to source another engine with lower miles :oops: Quote Share this post Link to post Share on other sites