16v205 9 Posted June 26, 2007 (edited) Hi Does anyone know which of the two are the best rods to use? They will be used in a engine with 88mm crank running around 11.5:1. Engine wont be reving more than 7500rpm as it runs out of steam around 7200rpm. Forged pistons are being custom made so will be made to suit the best rod. I guess id like to use the mi16 rod on the left as its much lighter and has already been shot-peened. But is it strong enough for 200+bhp? The s16 on the right is a fair bit heavier and looks more robust but is it actually any stronger? Cheers Rich Edited June 26, 2007 by 16v205 Share this post Link to post Share on other sites
RossD 43 Posted June 27, 2007 Hi Does anyone know which of the two are the best rods to use? They will be used in a engine with 88mm crank running around 11.5:1. Engine wont be reving more than 7500rpm as it runs out of steam around 7200rpm. Forged pistons are being custom made so will be made to suit the best rod. I guess id like to use the mi16 rod on the left as its much lighter and has already been shot-peened. But is it strong enough for 200+bhp? The s16 on the right is a fair bit heavier and looks more robust but is it actually any stronger? Cheers Rich A bit of a tangent, but what are the lengths of those rods? If you can get hold of 2.0 HDi rods, they are actually Forged steel as standard. They look like they are both cast?? At least then you know you would be getting a much tougher rod, rather than guessing with those two. The DW10 has a stroke of 88mm, so the rod length os going to be pretty similar. Share this post Link to post Share on other sites
Mandic 0 Posted June 27, 2007 I cannot comment on rod strength, but usually it is not improtatnt how much hp will You run. It is peak torque and max RPM. In NA application where You are dependent on atmo pressure You are pretty much limited how much torque You can run, so std rod will surely take more or less same peak torque as in std. engine. So it's the revs that might potentially kill it, but people seem not to have any troubles reving to 7500 just by changing std bolts for ARP ones. There is another thing to consider, Mi16 and S16 rods are not the same length, one being 143 and the other 152mm. So You can not use the in the same block (well You can skim S16 one, but I'm not sure about this). But if You are not conserned about a bit more weight at the front end, You should use S16 block, Mi16 crank and S16 rods. By fitting 88mm crank it will reduce piston to deck clearance from 3mm to 2mm, which is a good thing. plus using longer rod in will reduce pistons speeds compared to Mi16 engine. Cheers Ziga Share this post Link to post Share on other sites
brianthemagical 1 Posted June 27, 2007 you may need to consider the rod/stroke ratio and the gudgeon pin to deck height with the two rods. Share this post Link to post Share on other sites
James_R 3 Posted June 27, 2007 As said above I'd just go with the longer rod. Share this post Link to post Share on other sites
16v205 9 Posted June 27, 2007 RossD - I didnt know that about the hdi rods. I know where theres a set in good condition but dont think my gf would be too happy if I take the picasso apart for spares though as between the two of us its the only reliable car weve got I think because its been so long since my cars been on the road I just want to get it going now, so im limiting the choice to what ive got in the garage on the shelf now. I forgot to mention in the first post im using a cast iron gti-6 block and the pistons will be 87.5mm. The final deck height of the piston on a shorter rod if its just a few mm lower shouldnt be too much of a issue as I will get the block taken down to requirements. The last engine made 161lb/ft @ emerald so im assuming similar figures may be a good starting point for this one. So given the choice what would you guys use? Are the mi16 conrods strong enough with arp bolts for reliable everyday use? assuming max torque of 170lbft and 7200rpm? Cheers Rich Share this post Link to post Share on other sites
Miles 331 1 Cars Posted June 27, 2007 Long rod's are by far the best one's Share this post Link to post Share on other sites
KRISKARRERA 2 1 Cars Posted June 27, 2007 Bloody hell, the top bit that connects it to the piston is so much thicker on the 2 litre! Share this post Link to post Share on other sites
M_R_205 5 1 Cars Posted June 29, 2007 RossD, hdi rods out of what? Share this post Link to post Share on other sites
Baz 421 Posted June 30, 2007 RossD, hdi rods out of what? Any 2.0 HDi engine i'd presume... Share this post Link to post Share on other sites
M_R_205 5 1 Cars Posted June 30, 2007 Any 2.0 HDi engine i'd presume... good point will tey be ok in a mi16, im soon to turbo it and want a cheap strong rod if there is such a thing Share this post Link to post Share on other sites
Mandic 0 Posted June 30, 2007 No, it is too long for Mi, Cheers Ziga Share this post Link to post Share on other sites
RossD 43 Posted June 30, 2007 (edited) No, it is too long for Mi, Cheers Ziga The 2.0 HDi (The old SOHC 90 and 110, unsure about the new 16v models) use forged rods. They are 145mm between centres. MI16 are 143 and 150 something aren't they? Might be able to get them to fit! The same rods can also be found on the DW8 engine (1.9 Non turbo) Source is this Peugeot spec document: http://www.christiantena.pwp.blueyonder.co...di/b1bbm2k3.htm Scroll down to "Connecting rods" Edited June 30, 2007 by RossD Share this post Link to post Share on other sites
petert 554 Posted July 1, 2007 (edited) All those Peugeot rods are drop forged! Other varieties could be aluminium, billet steel or sintered. Sintered powder rods have only recently been used in large 4 stroke engines. Unless you're going to build an 8000+ rpm screamer, use the S16 rods with new rod bolts, S16 spec. pistons and skim the block 1mm. Edited July 1, 2007 by petert Share this post Link to post Share on other sites
stux 0 Posted July 1, 2007 Long rod's are by far the best one's Can you explain me why it's better option. Share this post Link to post Share on other sites
Mandic 0 Posted July 1, 2007 Clearly can be seen that S16 rod is stronger, but if You take two rods with identical design, longer will be better due to lesser angle change, which leads to many advantages, such as lower piston speeds, better acceleration curve (in combination with burning rate and inlet flow), less skirt drag, ... Cheers Ziga Share this post Link to post Share on other sites
B1ack_Mi16 67 Posted July 5, 2007 The S16 ones look the same as the T16 ones, so should handle lots of torque at least. Share this post Link to post Share on other sites
