Upgrading to big turbo. 2020 Si. Any tips before I replace it?

RollinindaRoyce

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So I finally got the Vargas GC+ turbo. I have purchased the custom TSP tune. I realized I have some time before it comes in, but I want to be ready. I purchased the downpipe gasket already, but I heard that you need a new oil line gasket for the turbo? Does anyone know what I can get to prepare for the turbo install? Any gaskets I need or parts I might replace? This is going on a 2020 SI with 30,000 miles. Not upgrading the inlet pipe, itā€™s just too pricey for the small power gain. Any tips will be much appreciated! Pic is the only pic I have of the car. I donā€™t take pics of it really. All stock outside except wheels

Honda Civic 10th gen Upgrading to big turbo. 2020 Si. Any tips before I replace it? 90FA6AAB-A902-4CF5-9CDA-CAAF44E09775
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ChefRyeSi

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1st tip....the obvious change. 2nd tip, the TIP is worth it bc while the HP gain is minimal, it allows for more and CONSISTENT airflow which increase the efficiency of the turbo allowing it to move more air which means it CAN create the same power with less boost ie: 400whp on 30psi w/ TIP vs. 400whp on 38psi w/ stock TIP. Same thing for something like the Skunk2 manifold.

The GC+ should come with whatever you need gasket wise i think? But no, any feed lines are just transferred over from the stock unit just like any other "drop in" turbo. Hence the name. New gaskets are always good, something to look at is the oil feed line filter: https://prlmotorsports.com/products...filter-assembly-3?_pos=6&_sid=9b1d0fa49&_ss=r

Make sure all feed lines are TIGHT TIGHT TIGHT when installing. Had a "friend" who didnt tighten mine all the way and luckily noticed when i was driving away and called me back. Also get yourself a set of rampage studs. Worth the $100 or so
 

curlichfc1

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I donā€™t want to speak for the gc+ kit, but when I ordered the vargas gc turbo I needed to replace my downpipe gasket but I did what the post above said ordered off prls site, vargas sends all the studs for the turbo but not gaskets, I was told to replace all soft lines connecting to the turbo if it look worn which mine were replace them and that hardlines that run to the turbo can be reused if they are not worn. Other then that change the oil to 5w-30 or what I use is 5w40 and change my oil every 4k miles at the latest
 

Doc_Mello

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Wow, where to start! šŸ˜„

So, my thoughts here:
- Have you upgraded your clutch yet? Youā€™ll must before you can do the turbo upgrade.
- Agree about the Rampage Fab studs to connect the DP, and even the turbo to the manifold. Rampage sells a kit to replace all the studs from the block to the DP/FP connection.
- Maybe I over-prep, but I replaced all the gaskets from the block all the way down: block to turbo (Part No.: 18233-59B-004), turbo/DP (Part No.: 18234-59B-004), DP/FP (got a new one from 27won), and parts for the oil feed lines + the coolant lines: oil inlet gasket (Part No.: 15535-6A0-A00), oil return line gasket at the turbo (Part No.: 15544-59B-003) & new screen (Part No.: 15533-59B-003), and the coolant gasket (Part No.: 19524-59B-004).
- Hereā€™s my Build Thread on my GC+ install. Thatā€™s the prep, but hereā€™s the actual install. Happy reading!
- Beware when removing studs. Theyā€™re known to snap. Use PB blaster as described.

I also agree about the inlet pipe. I have one coming, partially for that reason.

I used 0W-40, as recommended by Vargas. Up to you.

I would be careful with over-tightening the nuts for the coolant line and the oil return line. The spec, IIRC, is ~10ft-lbs. I didnā€™t use a torque wrench on those, and I cinched them down, but not too tightly. They donā€™t have to be macked. No leaks thus far. The oil inlet is 21ft-lbs, I think. Check SM9 of the manual.

Qs welcomed! Iā€™ll also tap @Sport-injected @Neddih @Ronny2019 for their insight.
 

Ronny2019

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Awesome he joined the GC-GC+ Crew. You will love it šŸ˜ but. The turbo comes with the turbo and dp studs that is it you need to get all the gaskets and oils that doc said and you should be golden. Are you running flex with this set up? Are you stock block? I would suggest a turbo blanket. For me it helps with intake temps tremendously. Good luck

Honda Civic 10th gen Upgrading to big turbo. 2020 Si. Any tips before I replace it? ACCB7609-120B-4386-8229-74EF52ADEAF5


Honda Civic 10th gen Upgrading to big turbo. 2020 Si. Any tips before I replace it? F2C5AD65-6402-47CA-99D1-1C483CE33BFF
 


Neddih

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I think what everyone here said has covered it pretty much. When I installed mine I replaced the downpipe gasket and manifold gasket only and reused all of the rest because they were in good shape.
 
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RollinindaRoyce

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Wow, where to start! šŸ˜„

So, my thoughts here:
- Have you upgraded your clutch yet? Youā€™ll must before you can do the turbo upgrade.
- Agree about the Rampage Fab studs to connect the DP, and even the turbo to the manifold. Rampage sells a kit to replace all the studs from the block to the DP/FP connection.
- Maybe I over-prep, but I replaced all the gaskets from the block all the way down: block to turbo (Part No.: 18233-59B-004), turbo/DP (Part No.: 18234-59B-004), DP/FP (got a new one from 27won), and parts for the oil feed lines + the coolant lines: oil inlet gasket (Part No.: 15535-6A0-A00), oil return line gasket at the turbo (Part No.: 15544-59B-003) & new screen (Part No.: 15533-59B-003), and the coolant gasket (Part No.: 19524-59B-004).
- Hereā€™s my Build Thread on my GC+ install. Thatā€™s the prep, but hereā€™s the actual install. Happy reading!
- Beware when removing studs. Theyā€™re known to snap. Use PB blaster as described.

I also agree about the inlet pipe. I have one coming, partially for that reason.

I used 0W-40, as recommended by Vargas. Up to you.

I would be careful with over-tightening the nuts for the coolant line and the oil return line. The spec, IIRC, is ~10ft-lbs. I didnā€™t use a torque wrench on those, and I cinched them down, but not too tightly. They donā€™t have to be macked. No leaks thus far. The oil inlet is 21ft-lbs, I think. Check SM9 of the manual.

Qs welcomed! Iā€™ll also tap @Sport-injected @Neddih @Ronny2019 for their insight.
Hey thank you for that write up! That helps a ton. So letā€™s see here.
Clutch is Emans type R retrofit. Had him install it. We both live in Ventura.
I am going to order the 8 pack of rampage studs to be safe. When replacing my downpipe I snapped one stud and thatā€™s a big reason why Iā€™m replacing the turbo.
Did you get all these gaskets from Honda? I can head down there and get them if thatā€™s where you went. I do want to be safe with it and get the proper oil. Thank you for the specs too! I have all the torque wrenches I need and will be using them to do it all. Luckily Iā€™m in the local mechanics program and have most the stuff I need on hand. Also I am using flex fuel already and am getting the tune for flex fuel. Trying to get all I can on a stock block without going over board and I will let DRob know that. Other than that Iā€™m stoked for the install, just always worried about the damn studs coming out! Those things seize up so easy! Iā€™ll be soaking them in PB days before.
 
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RollinindaRoyce

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Awesome he joined the GC-GC+ Crew. You will love it šŸ˜ but. The turbo comes with the turbo and dp studs that is it you need to get all the gaskets and oils that doc said and you should be golden. Are you running flex with this set up? Are you stock block? I would suggest a turbo blanket. For me it helps with intake temps tremendously. Good luck

ACCB7609-120B-4386-8229-74EF52ADEAF5.jpeg


F2C5AD65-6402-47CA-99D1-1C483CE33BFF.jpeg
Hey thank you! I wrote a long replay to doc. I will be looking into the blanket. Just purchased a ton of stuff, even bought the TIP last night from 27Won. I am using a stock block so Iā€™m not going too crazy. Trying to keep it in safe ranges. Also yes Iā€™m running flex fuel currently and will be getting the tune for that. Thanks for the suggestions!
 

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Hey thank you for that write up! That helps a ton. So letā€™s see here.
Clutch is Emans type R retrofit. Had him install it. We both live in Ventura.
I am going to order the 8 pack of rampage studs to be safe. When replacing my downpipe I snapped one stud and thatā€™s a big reason why Iā€™m replacing the turbo.
Did you get all these gaskets from Honda? I can head down there and get them if thatā€™s where you went. I do want to be safe with it and get the proper oil. Thank you for the specs too! I have all the torque wrenches I need and will be using them to do it all. Luckily Iā€™m in the local mechanics program and have most the stuff I need on hand. Also I am using flex fuel already and am getting the tune for flex fuel. Trying to get all I can on a stock block without going over board and I will let DRob know that. Other than that Iā€™m stoked for the install, just always worried about the damn studs coming out! Those things seize up so easy! Iā€™ll be soaking them in PB days before.
Awesome! Looks like youā€™re in good shape! Have fun with the install, especially getting the OEM inlet pipe out, and I srsly hope you have no problems with the turbo support bracket underneath. šŸ˜–šŸ˜–šŸ˜–šŸ¤¬šŸ¤¬šŸ¤¬
 

Neddih

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Awesome! Looks like youā€™re in good shape! Have fun with the install, especially getting the OEM inlet pipe out, and I srsly hope you have no problems with the turbo support bracket underneath. šŸ˜–šŸ˜–šŸ˜–šŸ¤¬šŸ¤¬šŸ¤¬

Aha! So it wasn't just me :rofl: the bracket drove me nuts
 


Doc_Mello

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Aha! So it wasn't just me :rofl: the bracket drove me nuts
Nope, me too. I used your post for guidance on how to shave it down, actually. šŸ™ŒšŸ¼ Not sure why you and I had probs, but others didnā€™t. šŸ¤·šŸ¼ It mightā€™ve been because of the torque sequence, but that makes me concerned about their cars, not ours.
 

ChefRyeSi

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I donā€™t want to speak for the gc+ kit, but when I ordered the vargas gc turbo I needed to replace my downpipe gasket but I did what the post above said ordered off prls site, vargas sends all the studs for the turbo but not gaskets, I was told to replace all soft lines connecting to the turbo if it look worn which mine were replace them and that hardlines that run to the turbo can be reused if they are not worn. Other then that change the oil to 5w-30 or what I use is 5w40 and change my oil every 4k miles at the latest
Xw-40 is so thick....my main concern for the future
 

ChefRyeSi

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Awesome he joined the GC-GC+ Crew. You will love it šŸ˜ but. The turbo comes with the turbo and dp studs that is it you need to get all the gaskets and oils that doc said and you should be golden. Are you running flex with this set up? Are you stock block? I would suggest a turbo blanket. For me it helps with intake temps tremendously. Good luck

ACCB7609-120B-4386-8229-74EF52ADEAF5.jpeg


F2C5AD65-6402-47CA-99D1-1C483CE33BFF.jpeg
Hey! The only other Si member I've seen with the 2 blanket setup, nice. How'd you get yours to stay on with something to hold it? Mine wouldnt velcro
 

ChefRyeSi

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Been running it for 37k milesā€¦
Not saying anything is bad/the wrong choice just saying thatā€™s quite thick for a platform with such small oil journals. Iā€™m sure itā€™ll be ok considering the EU market runs 0w-30 from the factory.
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