does anyone know the length of the factory connecting rod? i can seem to find it anywhere and know one seems to know. i dont have the necessary tool to measure it properly (whatever tool that would be). its not overall length, its center of hole to center of hole. thanks in advance

 

nothin huh?

 

sorry man. I wont know until i pop the bottom end...

I think its comming though, im up to 13psi

 

if you're worried about the rods, why not just get the crower replacement rods?
http://www.raceeng.com/pc-8538-46-cr...1nzfe-set.aspx

@ bjurches - 13psi?! with what sc/tc? and are you still on the stock rods? just wondering cause i thought that kind of boost was impossible unless quite a few parts were upgraded like the front axels/drivetrain, rods and whatnot? i'd love to get that kind of boost...

 

check ur PM, i dont want to jack his thread.

 

i just need to know the length, having custom ones made up from another company. thats a good find though, does anyone have them in their scion yet?

 

several do. and they work great! theres a few on here and on club xB that have them. big diffrence betwee them and the stocks.



crowers on the left, stocks on the right.

 

Hi all, i'm new to this site, uk yaris owner.

the factory con rod legnth is 140.8mm which is at 10.5:1 compression ratio.

I was looking into getting custom rods made at 139.5mm which would of dropped the compression to 9:1 but there £1000 so i'd suggest if your thinking of custom rods don't!

Hope this helps.

also the thickness of the rod is 17.81mm with a gudgen pin diameter of 18.02mm and a big end diameter of 37.040mm (legnthways) and 37.025mm across the join.

If you don't mind me asking how much are these rods going to cost and what are you having made?

i.e. will you be going for low compression and will they be cheap because i may be interested in buying a set if they are.

Brad =)

 

the rods shown above
the right one is what is Stock and the left being the thicker and stronger rods of the same size.

most are just going for forged piston kits to lower compression. right not, the only custom side of the compression is raising the compression for either torque'less NA or being gutsy and raising compression to handle the same FI/SC boost.

i don't see any reason to go with custom rods really... you can just go the route of gettign those crower rods and then picking up a wiseco piston kit from http://www.importperformanceparts.net/ *go to hp engine kits, toyota, should kit number 17 or 18, it's labeed under the echo but is the same exact engine and several have used this kit with great results.* being it comes in compression ratios of 8.5:1, 9.0:1, 9.5:1 and 10.0:1 end they are forged of lighter metal aswell and handle more abuse then the stock pistons. it would be best to go that route instead of getting custom rods and keep the stock pistons which could crack from the abuse.

theres also these guys who have a 9.5:1 compression kit by phone order but i haven't heard of anyone using them but i have heard of the brand name before and havn't heard anythingbad about them. http://raceprecision.com/forums/viewtopic.php?t=51

i also notice though that the Wiseco piston kit is a low silicone alloy while the RP piston kit is a high silicone alloy. i don't know much much about that part, if anyone would care to elaborate that part...

 

It seams like the weak point in the engine as with most engines is the conrod as the stock pistons are pretty good so i have been looking at getting custom rods made a bit shorter to drop the compression ratio and still use the same pistons.

This will allow more boost and should be fine to 250-300 BHP

So far i have a quote for $729 for a set of rods which should allow me to handle similar boost as replacing the rods and pistons at a cost of ~$1700 a nice saving i think.

Another thing is that the stock pistons are about the same weight or less as expensive pistons, and already have good squish ad clearence with the head which should allow 8k rev limit.

I should be trying this theory out in the next few months as the rods take a long time to make but if the results are good then i will be releasing details of all the engine work i have done which should provide a cheap solution to upping the boost on this engine.

Hope that all makes sence as i do tend to mix my words.

Brad =)

 

wow 8k, gota let me in on that! haha that would be nice.

also, lowering the compression does allow for more boost, but you will still result in the same amount of power at the end. diffrence is, you've got an "aww effect going on with having more boost then everyone else. but someone with the same settup, stock compression and 14psi boost would be the exact same power if you were to have a compression of 9.5:1 and 17psi boost, the resulting compression is just about the same *this being based off the 1NZFE with the GT2554R turbo*. it would matter what turbo or engine, the concept is still the same and will end up in the same power gain.

for example, you want 9.0:1 compression ratio and say you want to hit... 250hp, now basing this on the 1NZFE with the GT2554R turbo, you would need about 18psi full boost. stock compression of 10.5:1 with about 13.8psi full boost would be the same thing, you just don't have that "aww" factor that makes it seem more powerful then what it really is and is more for show. you get a louder BOV sound and a louder intake sound aswell, but power wise... it's the same.

 

^he said it.

realisticly, lower compression= less chance of detonation

 

and a ton of cash just to reduce that chance... but worth it if you want to limit that risk.

but if you're rich... psshh... throw 40psi at it and see what happens...

 

<------------- far from rich but workin on it lol.