Carbahn 4.6L Stroker build/long term review

[OmairK]

Are they boring out throttlebodies still? Is that still a thing?

[spammysammich]

Originally Posted by OmairK

Are they boring out throttlebodies still? Is that still a thing?

I haven’t seen those offered since the OG Dinan days.

[SYT_Shadow]

Originally Posted by OmairK

Are they boring out throttlebodies still? Is that still a thing?

It's still a thing, and I had them as well

[e90sanmarino]

Here's a brief update from the weekend progress before final assembly onto the subframe and chassis:

1. The engine harness has been installed following the repairs mentioned in the previous post.
2. New CCW oil pump with related pulleys, tensioners mentioned in previous post has been installed.
3. New water hard line has been installed.
3. The clutch and flywheel have been transitioned to the new engine.
4. Various components such as the clutch fork, throwout bearings, guide tube, and plastic pin in the transmission have been replaced as part of maintenance procedures.

[e90sanmarino]

All components have been securely fastened to the subframe and are ready for the engine bay. I'm aiming for this weekend for the the initial startup.

[Brosef]

awesome thread! congrats on the new motor. I think a stroker could be in my future

subscribing for future updates

[e90sanmarino]

As per the previously outlined schedule, today marked the successful start up of the stroker engine. Following the 9 liters of break-in oil, coolant, and power steering fluid, I proceeded to prime the vehicle until receiving a low battery warning on the dashboard. Notably, during this process, fuse number 70 and the crankshaft position sensor were unplugged. Subsequently, the engine commenced operation without issue. Maintaining the engine speed at 1500 rpm, I ensured optimal circulation of the oil pump. Upon reaching operating temperature, I varied the rpm within a range not exceeding 3000 rpm, observing a discernible improvement in both idle smoothness and rev responsiveness over time. After a 30-minute runtime, I promptly conducted an oil flush to expel any residual debris and metal flakes.

Outlined below is my strategy for the forthcoming break-in period:

1. Mileage 0-100: Utilizing Torco break-in oil, adhere to a maximum rpm threshold of 4000.
2. Mileage 100-500: Continuation with Torco break-in oil, gradually increasing rpm to a maximum of 5500.
3. Mileage 500-1200: Transition to 10-60 OEM oil with Redline additive, while maintaining a maximum rpm limit of 6500.
4. Mileage 1200-2000: Employing 10w-60 OEM oil, gradually extend the rpm range up to 7500.

However, despite the successful engine start, several setbacks were encountered:

1. The transmission drain plug fractured upon application of torque to specification.
2. The clutch slave unit experienced a failure, resulting in clutch pedal going straight to the floor.

Anticipating the acquisition of replacement parts next week, I aim to resume the engine break-in process by the week's end. Attached is a clip showcasing the initial startup, along with a visual assessment of the oil condition post start up:

https://youtube.com/shorts/ww9-nvPkV..._ydM6ITitYUU7S

[Especial82]

Hello, do you notice oil temperature is slightly higher than previous? I recall in the day drive my oil temp is pointing at 100 or slightly lesser. But after installing the 4.6L, the oil temp is slightly more pointing more than 100.

[e90sanmarino]

Originally Posted by Especial82

Hello, do you notice oil temperature is slightly higher than previous? I recall in the day drive my oil temp is pointing at 100 or slightly lesser. But after installing the 4.6L, the oil temp is slightly more pointing more than 100.

Hi, yes I noticed the oil temp gauge is slightly higher than 100. Although today was quite hot and I was reving engine for 30 mins. Also, I was on break-oil. What was your experience like? You noticed that while driving?

[Especial82]

I just complete my break-in. But the tune map seems gives me checklight (increased emissions). Waiting for them to get back to me. But I would say during the break-in period can feel the car very responsive. I can only rev it once i sort out the tune file.

[omgzirra_exe]

Originally Posted by e90sanmarino

Outlined below is my strategy for the forthcoming break-in period:

1. Mileage 0-100: Utilizing Torco break-in oil, adhere to a maximum rpm threshold of 4000.
2. Mileage 100-500: Continuation with Torco break-in oil, gradually increasing rpm to a maximum of 5500.
3. Mileage 500-1200: Transition to 10-60 OEM oil with Redline additive, while maintaining a maximum rpm limit of 6500.
4. Mileage 1200-2000: Employing 10w-60 OEM oil, gradually extend the rpm range up to 7500.

this is pretty similar to when i did my 4.4L break in proceedure.

by far the most stressful part after installation... constant thoughts where flowing thru my head.. and hearing sounds that didn't exist lmao.

although i do note, i evidently stopped using 10W-60 on the 4.4L and strictly only use 5W-50 from Redline/Amsoil/Motul

then the stress from tuning was another headache for me.

congrats on completing your build and swap!!!

Originally Posted by Especial82

I just complete my break-in. But the tune map seems gives me checklight (increased emissions). Waiting for them to get back to me. But I would say during the break-in period can feel the car very responsive. I can only rev it once i sort out the tune file.

you also! congrats!

[e90sanmarino]

Originally Posted by Especial82

I just complete my break-in. But the tune map seems gives me checklight (increased emissions). Waiting for them to get back to me. But I would say during the break-in period can feel the car very responsive. I can only rev it once i sort out the tune file.

Wow that was really fast. How many miles was your break-in procedure. Hope CarBahn sorts out for you soon. Update us with the progress and your impression once you do.

[e90sanmarino]

[QUOTE=omgzirra_exe;31074727]this is pretty similar to when i did my 4.4L break in proceedure.

by far the most stressful part after installation... constant thoughts where flowing thru my head.. and hearing sounds that didn't exist lmao.

although i do note, i evidently stopped using 10W-60 on the 4.4L and strictly only use 5W-50 from Redline/Amsoil/Motul

then the stress from tuning was another headache for me.

congrats on completing your build and swap!!!

Thank you man! Yes, I’ve been hearing noises here and there too and got paranoid. I’m in Japan right now picking up some parts for the transmission and keep rewinding the clip I took where I heard some noises. I thought I was the only one who had OCD lol.

May I ask why you change to 5W-50? I might do it also since all the OEM oil I need to import from US or Germany while 5W-50 is readily available here.

[omgzirra_exe]

[QUOTE=e90sanmarino;31079438]

Originally Posted by omgzirra_exe

this is pretty similar to when i did my 4.4L break in proceedure.

by far the most stressful part after installation... constant thoughts where flowing thru my head.. and hearing sounds that didn't exist lmao.

although i do note, i evidently stopped using 10W-60 on the 4.4L and strictly only use 5W-50 from Redline/Amsoil/Motul

then the stress from tuning was another headache for me.

congrats on completing your build and swap!!!

Thank you man! Yes, I’ve been hearing noises here and there too and got paranoid. I’m in Japan right now picking up some parts for the transmission and keep rewinding the clip I took where I heard some noises. I thought I was the only one who had OCD lol.

May I ask why you change to 5W-50? I might do it also since all the OEM oil I need to import from US or Germany while 5W-50 is readily available here.

tbh, it just after testing different grades.. and brand

a good thing to remember, once you build your motor it no longer follows "oem" suggestions at least in my opinion. so you really need to go out of your way and test what works best, and inspect it and see how your engine behaves.

for me i find that 300V/RedLine/Amsoil in 5W50 is what my engine enjoyed. after all the work done to it.

[Especial82]

Carbahn recommended break-in is 1000km but I go at least 2000km to play safe. I am now sorting out with Ani for the my tune file. She is very responsive

[e90sanmarino]

[QUOTE=omgzirra_exe;31080952]

Originally Posted by e90sanmarino

tbh, it just after testing different grades.. and brand

a good thing to remember, once you build your motor it no longer follows "oem" suggestions at least in my opinion. so you really need to go out of your way and test what works best, and inspect it and see how your engine behaves.

for me i find that 300V/RedLine/Amsoil in 5W50 is what my engine enjoyed. after all the work done to it.

Thanks for your input! I will be sure to experiment with different oils once Im done with the recent batch of 10W-60 I ordered (30L )

[e90sanmarino]

Originally Posted by Especial82

Carbahn recommended break-in is 1000km but I go at least 2000km to play safe. I am now sorting out with Ani for the my tune file. She is very responsive

Yes that is my plan also but only covered 80km so far . That is great to hear that at least their software department is responsive

[e90sanmarino]

Finally, I have started the vehicle's break-in period. I am gradually acclimating the stroker engine, restricting throttle input to no more than half and ensuring that the RPMs remain below 4000 for the first 160 kilometers. Having already covered 80 kilometers, I can attest to its smooth operation and performance. Despite my efforts, maintaining the engine speed below 4000 RPM proves challenging, as the engine exhibits a strong inclination to rev higher.

Further break-in procedures will be conducted tonight, with an oil change scheduled for tomorrow.

However, I have observed an issue following my initial drive. Upon cold start, there is a noticeable chatter or slapping noise at idle from the belly pan area. While I suspect it might be related to forged piston slap, I cannot confirm its exact origin. Importantly, this noise ceases once the vehicle reaches operating temperature. I have already contacted Carbahn regarding this matter, but I am also interested in your insights. Tomorrow, I will inspect the oil for any irregularities.

Attached are recordings of the engine idling both at cold start and at operating temperature for your reference:

[amrazM]

forged pistons are pretty clacky when the engine starts up cold, they expand at a different rate than cast pistons which is why the noise goes away when the engine is hot.

[e90sanmarino]

Originally Posted by amrazM

forged pistons are pretty clacky when the engine starts up cold, they expand at a different rate than cast pistons which is why the noise goes away when the engine is hot.

Thank you for the clarification. I appreciate it, and I can now proceed with the engine break-in process with confidence

[e90sanmarino]

Today, I recorded a short clip while breaking in the engine. Despite only applying 1/3 throttle, the sound of the Eventuri Carbon Plenum is clearly audible. Having covered the initial 100 miles (160 km) of the break-in process today, I plan to change the oil tomorrow.

[omgzirra_exe]

Originally Posted by e90sanmarino

Thank you for the clarification. I appreciate it, and I can now proceed with the engine break-in process with confidence

Yeah, that noise is pretty much normal for "built" forged engines, and this is something I always mention. However, I'm curious as to what Carbahn will say, since VAC told me the noise was normal with forged components. I don't disagree with that, as I heard the same type of noise in my 2.3L stroker Evo 9, but didn't hear that noise in my stroked "F22C" from F20C (.2L stroked using OEM F22C crankshaft and OEM F20C pistons/rods), which only reinforces that it's limited to just the aftermarket forged parts from personal experience.

You can somewhat mitigate that with different oil, so you can test it out. Like I said, for me, I found Redline/300V 5W50 made things quieter, but I live in SoCal. Your mileage may vary in VN.

However, I still hear the noise if I'm putting my ear against my hood or fender on cold starts.