Comparison of "Base" 1.5T and "Si" 1.5T Connecting Rods

[charleswrivers]

One of the 3(?) cars that blew their engines a couple months back was running a claimed 27# of boost as I recall. Imagine the torque that would be made at 2500-3500 RPM... where the little turbo could actually provide enough CFM to feed the engine... couple that with cold weather so the air was very dense and... yeah... it's not surprising at all. That car was probably at or north of the mid-300 ft/lb if torque range at it's peak. Amongst the problems... bad plugs... the car not running right prior to wrecking their rods... running with the car having knock... I swear the group of guys were actually trying to kill their cars.

If you stay with the basemap's or go with a reputable tuner, acknowledging your stock clutch might not hold... you oughta be fine. Go off the beaten path by making massive, ignorant adjustments to a basemap, not datalogging or ignoring the data that's showing the tune is no good, and ignoring clear signs something is wrong with your car and beating it to death anyways... well... yes... it shall die.

I'd be comfortable with a non-Si running 190 hp until it's wheels fall off. As it is... I'd be comfortable with my Si making well more than that as long as I'm not aiming for the stars with regard to mid-range torque.

1/2 again stock power or ~200hp(or ft/lbs)/liter without internal mods are numbers I've been comfortable with even before I got this car. Funny enough, at least for an Si... they're about the same. 300 hp and 300 ft/lbs of torque. Anything past that concerns me. As it is, I doubt I can hit the HP number without either 1) another turbo or 2) all bolt on and flex fuel... so no worries. I *can* reach over 300 ft/lbs of torque on the stock turbo, though my stock clutch can't take it. How do I prevent it? Limit boost where torque peaks... thus limiting it. No problem there.

I still think those car-killing folks were practically trying to do it... once they said what they had done leading up to the failure and what evidence they had ignored prior to the failure occuring. It wasn't a make-one-adjustment-and-boom right-out-the-gate kind of scenerio.

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[totopo]

The only engines Im aware of blowing up were custom tuned by the user in cold climates with possible bad gas as well. My ex-t has been running either Vit custom tunes or Ktuner starter 21 tunes for a year with no issues. There are lots out there like me, if you aren't pushing the limits to the max you can run well over his quoted 197 hp and maintain oem like reliability.

One of the 3(?) cars that blew their engines a couple months back was running a claimed 27# of boost as I recall. Imagine the torque that would be made at 2500-3500 RPM... where the little turbo could actually provide enough CFM to feed the engine... couple that with cold weather so the air was very dense and... yeah... it's not surprising at all. That car was probably at or north of the mid-300 ft/lb if torque range at it's peak. Amongst the problems... bad plugs... the car not running right prior to wrecking their rods... running with the car having knock... I swear the group of guys were actually trying to kill their cars.

If you stay with the basemap's or go with a reputable tuner, acknowledging your stock clutch might not hold... you oughta be fine. Go off the beaten path by making massive, ignorant adjustments to a basemap, not datalogging or ignoring the data that's showing the tune is no good, and ignoring clear signs something is wrong with your car and beating it to death anyways... well... yes... it shall die.

I'd be comfortable with a non-Si running 190 hp until it's wheels fall off. As it is... I'd be comfortable with my Si making well more than that as long as I'm not aiming for the stars with regard to mid-range torque.

1/2 again stock power or ~200hp(or ft/lbs)/liter without internal mods are numbers I've been comfortable with even before I got this car. Funny enough, at least for an Si... they're about the same. 300 hp and 300 ft/lbs of torque. Anything past that concerns me. As it is, I doubt I can hit the HP number without either 1) another turbo or 2) all bolt on and flex fuel... so no worries. I *can* reach over 300 ft/lbs of torque on the stock turbo, though my stock clutch can't take it. How do I prevent it? Limit boost where torque peaks... thus limiting it. No problem there.

I still think those car-killing folks were practically trying to do it... once they said what they had done leading up to the failure and what evidence they had ignored prior to the failure occuring. It wasn't a make-one-adjustment-and-boom right-out-the-gate kind of scenerio.

Geez, do you guys own stock in ktuner or something?

I'm not saying if you breath at your ecu your motor is going to blow up. Like i'm not talking about how much power you can lay down for one quarter mile and not pop your rod instantly. But some people do care about OEM-like reliability.

Like, if you take 1,000 engines in 1,000 1.5t civics, what percentage make it to 100,000? It should be pretty high. For Honda, I expect my civic to make it to 100k miles. how many will make it to 150,000? Probably a decent amount. How many will make it to 200,000? quite a bit less. If i kept the civic that long I would be pleasantly happy that it made it that far.

So if you take 1,000 engines and slap on the base ktuner/hondata/vit tune on it, what percentage will make it to 100,000 miles? Are you saying the same? I'm not saying it's 0, but I bet the percentage that makes it to 100,000 should be less than a stock tune. How much less is the big question and probably only honda knows the answer.

If you think it is the same, then why did Honda change the part between the 1.5t and si when they didn't have to? why does the CRT with more tq have the Si rod instead of the 1.5 rod? They obviously didn't change the whole motor or much of it, just select parts that need to take some more tq. You think Honda wouldn't make more power out of the 1.5t if they could? why do you think they chose the power levels they do? Like is it just happenstance that when they increase the tq by 15% they increase the hardness of the rod by 15%?

 

[dallasjhawk]

Geez, do you guys own stock in ktuner or something?

I'm not saying if you breath at your ecu your motor is going to blow up. Like i'm not talking about how much power you can lay down for one quarter mile and not pop your rod instantly. But some people do care about OEM-like reliability.

Like, if you take 1,000 engines in 1,000 1.5t civics, what percentage make it to 100,000? It should be pretty high. For Honda, I expect my civic to make it to 100k miles. how many will make it to 150,000? Probably a decent amount. How many will make it to 200,000? quite a bit less. If i kept the civic that long I would be pleasantly happy that it made it that far.

So if you take 1,000 engines and slap on the base ktuner/hondata/vit tune on it, what percentage will make it to 100,000 miles? Are you saying the same? I'm not saying it's 0, but I bet the percentage that makes it to 100,000 should be less than a stock tune. How much less is the big question and probably only honda knows the answer.

If you think it is the same, then why did Honda change the part between the 1.5t and si when they didn't have to? why does the CRT with more tq have the Si rod instead of the 1.5 rod? They obviously didn't change the whole motor or much of it, just select parts that need to take some more tq. You think Honda wouldn't make more power out of the 1.5t if they could? why do you think they chose the power levels they do? Like is it just happenstance that when they increase the tq by 15% they increase the hardness of the rod by 15%?

they choose the power level so they can maintain their longevity and get good mpgs and meet EPA/CAFE standards. Honda even said, their longevity benchmark is 300k miles. As with all things, the maintenance you do will determine your longevity. If you run a tuned car and keep it well maintained why would the car not maintain its oem longevity. They clearly dont tune the car from the factory on the extreme edge. They always leave headroom. They gave the SI what they did because people buying an SI are more likely to be more abusive to their cars than the regular ext buyer. No I don't own stock in Ktuner, but I would if I could

 

[charleswrivers]

No I don't own stock in Hondata/Ktuner.

I have been modifying turbo cars all if my driving life. I've never had an issue adhering to my 'rules' on stock internals ~20 years and 5 turbo cars... including the 2 I currently have.

There is a certain safety margin built into the cars... as with all mechanical things. What that is, I cannot tell you... and Honda will never tell us. Why would a CRV that is rated to tow and would appreciate more low end torque for that purpose and to move it's substantially higher weight (~3400-3600 lbs, depending on trim) around be coupled with the 9 vane turbo that makes peak torque later? Makes no sense to me. But... hey... I'm not a car designer. Why does the Si and CRV share the essentially the exact same engine for two potentially very different uses? Not too sure. Not an engineer. It'd make sense the CRV oughta have a robust drivetrain to move potentially >5000 lbs of weight between it and it's little trailer... not counting passengers. Maybe with the R coming out as the *real* performance Civic, they shrugged... slapped the slightly beefier rodded CRV engine, raised the boost pressure up near the end of the efficiency island and called it good. I wish I had a buddy that worked at Honda's engineering side.

Honda said they limited the Si's engine for longevity... one year after the non-Sis came out and the same time as the CRV following likely several years of testing of a highly modified version of a 'tiny' engine that was used to nudge Honda's little cars around in NA form.

This being a relatively new platform... your question of stock vs tuned cars making it is something we'll all find out together over the next 5-10 years. The safe money in tuning is to buy a known quanity 'old' car that's cheap, modifyable and who's platform has it's history known. Had you told the Fit/Jazz owners 15 years ago that their little engine would eventually have forced induction and replace the K-series engine across the Accord, Civic and CRV with better performance than either the K20 or K24 could provide... I think you'd of had some doubters.

I bet you're right Honda knows... to a certain extent what the Civics could do. Given competitors like the GTI and GTI Sport that make 210/220 hp respectively... it makes sense they would want to match competitors numbers... but didn't. Is it really a weak motor? It is planned obselecence and they may release a higher output engine via essentially a tune only on a midcycle refresh? VW is already stating they'll have a 250 hp GTI come around 2019, so the Si would lag greatly behind at 205 hp.

Ever feel like a beta tester when a car company releases a vastly modified powertrain?

The answers to your questions will only come in time. We're developing the history of this platform that 5 years from now, people will be able to know and enjoy in the present. My car has a modded basemap, intake and nothing else. I understand that my warranty maybe out the window... but I am gambling... confidently... that it'll be fine. If it goes south, I have the money and ability to fix it. If someone doesn't feel this way... or would be ruined if things went south... then I'd recommend they stay stock and enjoy their car as it is.

 

[peterletran]

One of the 3(?) cars that blew their engines a couple months back was running a claimed 27# of boost as I recall. Imagine the torque that would be made at 2500-3500 RPM... where the little turbo could actually provide enough CFM to feed the engine... couple that with cold weather so the air was very dense and... yeah... it's not surprising at all. That car was probably at or north of the mid-300 ft/lb if torque range at it's peak. Amongst the problems... bad plugs... the car not running right prior to wrecking their rods... running with the car having knock... I swear the group of guys were actually trying to kill their cars.

If you stay with the basemap's or go with a reputable tuner, acknowledging your stock clutch might not hold... you oughta be fine. Go off the beaten path by making massive, ignorant adjustments to a basemap, not datalogging or ignoring the data that's showing the tune is no good, and ignoring clear signs something is wrong with your car and beating it to death anyways... well... yes... it shall die.

I'd be comfortable with a non-Si running 190 hp until it's wheels fall off. As it is... I'd be comfortable with my Si making well more than that as long as I'm not aiming for the stars with regard to mid-range torque.

1/2 again stock power or ~200hp(or ft/lbs)/liter without internal mods are numbers I've been comfortable with even before I got this car. Funny enough, at least for an Si... they're about the same. 300 hp and 300 ft/lbs of torque. Anything past that concerns me. As it is, I doubt I can hit the HP number without either 1) another turbo or 2) all bolt on and flex fuel... so no worries. I *can* reach over 300 ft/lbs of torque on the stock turbo, though my stock clutch can't take it. How do I prevent it? Limit boost where torque peaks... thus limiting it. No problem there.

I still think those car-killing folks were practically trying to do it... once they said what they had done leading up to the failure and what evidence they had ignored prior to the failure occuring. It wasn't a make-one-adjustment-and-boom right-out-the-gate kind of scenerio.

I think I'm one of those idiots ... but yes ... always go with a reputable tuner.
I slapped on the hondata +9 and ignored signs of mechanical problems, so the blame is all on me.
On another note, anyone know how much a dealership might charge to replace an engine?
-or-
Should I attempt to get a used one and put it in myself?

charleswrivers,
You're being very informative and I agree with everything you're saying.
The 1.5 turbo was designed primarily for economic purposes.
With a small displacement engine, you lose a lot of power, but
with the help of a turbo and various engine management (i.e. timing)
that little engine could still be efficient but have a little more "umph".
I'm sure if I hadn't played around with my tune, the engine could've lasted at least 200k miles.

 

[Syntek]

Weren't the base 1.5T engines stress tested to 300HP anyway? I could have sworn I read something that Honda did that to this engine.

 

[CVT_Squad]

So the SI rods are 5% stronger?

I'm surprised Honda bothered.

 

[totopo]

So the SI rods are 5% stronger?

I'm surprised Honda bothered.

15% stronger for 15% more torque... looks like both have a similar margin of reliability?

 

[chestypuller]

i think this test is flawed, you cant test one of each rod and get accurate results, you need multipul of that part number, then test them and get a overall hardness. then do the same with the standard rods, different batches could have that much variation in them alone.

 

[D-RobIMW]

i think this test is flawed, you cant test one of each rod and get accurate results, you need multipul of that part number, then test them and get a overall hardness. then do the same with the standard rods, different batches could have that much variation in them alone.

6 rockwell is a pretty significant difference in hardness.

I'm happy to test more of them if you'd like to ship batches my way.

 

[charleswrivers]

Yeah... I linked this thread on another. A lot of folks hadn't realized you did this for us awhile back. Folks will have to realize you're in the business of tuning and did us a favor and not a funded research lab.

It's still appreciated.

 

[chestypuller]

3 of each would tell you more forsure

 

[D-RobIMW]

3 of each would tell you more forsure

As stated earlier, I'm happy to test whatever you send me.

My shop's address is on both of my websites.

 

[chestypuller]

As stated earlier, I'm happy to test whatever you send me.

My shop's address is on both of my websites.

if we could get enough guys to pitch in id be willing to donate to the cause also. just cant afford to do the whole purchase.

 

[LilToTo17]

Brain Cower just released their new connecting rods for the 10th Gen Civics!!! BC6007 as seen on facebook and instagram posts

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