Tyler06 266 Posted April 8, 2014 what the tree trunk penis??? You can be the pioneer on that one. Too late bro ive been repping that one for 28yrs lol 2 slydog and unfamilia reacted to this Share this post Link to post Share on other sites
Tyler06 266 Posted April 8, 2014 It's all been said and done before but please stop making out its all your own idea, it happens way too much on this forum Couldn't agree more except for when someone thinks they own the designs for an engine idea and it should not be deviated from when it fails consistently. 1 slydog reacted to this Share this post Link to post Share on other sites
n00bus m@x1mus 465 Posted April 8, 2014 Ford followed this same principle with the evolution of the OHC 6, the Pre-xflow, 250 xflow and all earlier 4.0L OHC engines shared the same 5.88" rods, same big end bearing and gudgeon pin. But with the AU intech engine(and the hybrid EL series II built side by side) and all versions of the inline 6 since then they adopted a 6.05" rod and shorter skirt piston, this accompanied with a very shallow piston dish and larger head chamber and thin MLS head gasket puts a lot more energy above the piston mass and thus aids stable combustion over the face of the piston and decreases side wall friction, pushing the lot downwards as fast as it can meaning more torque. Share this post Link to post Share on other sites
slydog 7,873 Posted April 8, 2014 Couldn't agree more except for when someone thinks they own the designs for an engine idea and it should not be deviated from when it fails consistently. Â Well said Chris... Share this post Link to post Share on other sites
bigpaulo 239 Posted April 9, 2014 This is all really interesting! So if you were to go the long rod 250 setup, I assume youd have to get custom shorter pistons? Otherwise would they pop out of the block? Share this post Link to post Share on other sites
Clevo120Y 815 Posted April 9, 2014 ^^^correct, ACL used to have them on the shelf but no longer make them, I thought Mahle were going to start them again but I don't think it's happened. You can still get sets when they pop up for sale but they usally have a premium price now days. Share this post Link to post Share on other sites
bear351c 10,270 Posted April 9, 2014 Increased side skirt wear, as well. Share this post Link to post Share on other sites
ando76 4,354 Posted April 9, 2014 Yep - never seen a short rod engine yet that his come apart without significant wear on the piston skirt and that side of the block.  On the piston front I found a set of forged pistons to suit a 4.6l 'big bore' application that were perfect for a .020" x-flow block and 200 rod combination. They were made by DSS racing in the states and were around the $650-$700 mark for 8 pistons. cant for the life of me remember the part no. They may be an option. 1 gerg reacted to this Share this post Link to post Share on other sites
gerg 10,871 Posted April 9, 2014 I seem to remember some accounts of 347 stroker engines not lasting very long before piston and bore wear became an issue. Share this post Link to post Share on other sites
bear351c 10,270 Posted April 9, 2014 Not 100% sure, but seem to recall that the early 347 had a problem with the gudgeon pin bore, being too close to the oil ring groove. I believe it was fixed b y ACL or Federal Mogul or some such. (New design of piston.) 1 gerg reacted to this Share this post Link to post Share on other sites
gerg 10,871 Posted April 9, 2014 When Tickford had to come up with the T3 stroker engine, they tried all sorts of imported stroker kits and the engines did not pass the Ford durability tests, ending in "catastrophic failure". The boss of Tickford at the time described them as "rubbish". This is why the T3 5.6 contains many locally-sourced bits like a Harrop crank and Argo rods. I believe they used a custom piston too (unsure of brand) 1 bear351c reacted to this Share this post Link to post Share on other sites
n00bus m@x1mus 465 Posted April 9, 2014 A local engine builder is currently putting together a 250 xflow build for a guy i know and he is running an EF crank and BF turbo 6.05" rods, i question the owner about what slugs and deck height it will end up at and he hasnt a clue but said he trusted the builder to put it together, mind you he has got 35 years of tuff speedway xflow engines under his hat so id believe that he has something worked out. Share this post Link to post Share on other sites
Thom 6,650 Posted April 9, 2014 au- current run a longer rod than e series au on the left Ef on the right Share this post Link to post Share on other sites
n00bus m@x1mus 465 Posted April 9, 2014 Correct, heres a couple shots demonstrating the line of evolution from XF to BA  BA na on the left, EF in the middle, and XF on the right.   Vice versa here, notice the change in piston dish   Xflow right up to EL share the same rod, AU onwards got longer. 1 gerg reacted to this Share this post Link to post Share on other sites
Lord_fahrquhar 2,580 Posted April 10, 2014  Look I've found a 200 rod combo for my next build. 4 gerg, Clevo120Y, wagoon and 1 other reacted to this Share this post Link to post Share on other sites
Kiwi xf 0 Posted November 24, 2017 I have been looking into the 200 rods and spoolimports.com in Ozy have new ones at $795 a set and for around$1450 u get 200 rods Ross racing pistons rings ect Share this post Link to post Share on other sites
slydog 7,873 Posted November 24, 2017 And again...the Ross pistons used on the 200 rod are garbage. They will sink in the centre with any real hp timing heat or rpm. Seen it many many times. If using Spool use the CP piston as its a very good slug. 1 CHESTNUTXE reacted to this Share this post Link to post Share on other sites
