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420a stock internals turbo questions

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Really pistons are the best thing you can do. You can use srt4 pistons with 420a rods you just have to turn it 180 degrees. They sale for cheap but most of the time it is for stander bore so if you have not bored out the block you can maybe use them. Really pistons and rods is all you need to drop your compression when going turbo. If I were to to back and start over on my build I would have built up a 2.4l cloud car motor really that is the sweet spot and Its the same price to build as a 420a but cheaper parts and bit bigger motor plus the srt4 pistons and rods drop right in.
 
So just the pistons lower the compression ratio for the turbo (higher boost)?

And can I buy other pistons not str4?
 
Yes just pistons will lower the compression ratio (CR) of your motor. The srt4 are just a cheap way to go. They make all types of pistons for the 420a. If you look around a lot of people have piston and rod combos the only company that make h beam rods for the 420a is eagle and J.E and Wiseco make good forged pistons. I posted a link to the kit that is what you need to go for higher boost. You will want an 8.8:1 CR. You will also need ARP head studs to handle the extra pressure.



Wiseco Forged Pistons Mitsubishi Eclipse RS 2g 420a | eBay

EAGLE H-BEAM RODS MITSUBISHI ECLIPSE 95-99 N/T 420A | eBay
 
Yes just pistons will lower the compression ratio (CR) of your motor. The srt4 are just a cheap way to go. They make all types of pistons for the 420a. If you look around a lot of people have piston and rod combos the only company that make h beam rods for the 420a is eagle and J.E and Wiseco make good forged pistons. I posted a link to the kit that is what you need to go for higher boost. You will want an 8.8:1 CR. You will also need ARP head studs to handle the extra pressure.



Wiseco Forged Pistons Mitsubishi Eclipse RS 2g 420a | eBay

EAGLE H-BEAM RODS MITSUBISHI ECLIPSE 95-99 N/T 420A | eBay


So the pistons make the compression? That's based on their size and Shapiro right or what? (noob questions)

The headstuds I can just buy at an autopart store right?
 
Really pistons are the best thing you can do. You can use srt4 pistons with 420a rods you just have to turn it 180 degrees. .
No, no you can't without pin modification.

I'd really like to know where you got this information. (serious question because of misinformation parlayed by.....well, I'm just curious to know).

MB
 
I got the information from a supporting vender on dsmtuners awhile back. I do not remember who it was but They said that it was just the 180 turn and you are good to go. I remember checking it out and got it mixed up with the 2.4l motor swap I re-read all the old stuff that had been posted and missed the 2.4 part. Thank you for correcting me and apologize to the op for the wrong information.

It short team yes the piston is what makes the CR. It is the size of the piston (height). Ill drop in a link to how CR works so you can read up on it if you are interested in more information. As far as the head studs im not sure that a normal auto parts store will have them. A performance auto shop will have them do not use the OEM style head studs if you google ARP head studs they are stronger then the stock or OEM head studs.



Compression ratio - Wikipedia, the free encyclopedia
 
I remember checking it out and got it mixed up with the 2.4l motor swap I re-read all the old stuff that had been posted and missed the 2.4 part.]
Yup, 2.4 can play srt 4.

And as you alluded to in your post, there was vendor who gave out this incorrect information and I just wanted to be sure that they were not continuing to post on things they know nothing about.

MB
 
So here is my final list for my 95 gs turbo conversion

Turbo Manifold

12:1 FMU [special install for '95] (FMU IS THE SAME AS FPR CORRECT?)

Fuel Pump

Down Pipe

Air/Fuel Guage

Oil Catch Can (Can someone explain more? Specific kind?)

PCV block off plate (Can someone please explain what this is and it's purpose?)

Intercooler and Piping

Blow Off Valve (Any kind right?)

t3/t4 Turbo

Waste Gate

Boost Guage

Oil Feed/Return

Boost Controller


I need no FCD or Missing Link or Fueld Return because I have 95 yes?

I have to modify my stock FPR correct? (Can someone provide details about this?)



Am I all set with this? Anything to add or do?
 
12:1 FMU [special install for '95] (FMU IS THE SAME AS FPR CORRECT?)

I have to modify my stock FPR correct? (Can someone provide details about this?)

http://www.dsmtuners.com/forums/420a-turbo-conversion/339520-95-fmu-install.html

Blow Off Valve (Any kind right?)


I need no FCD or Missing Link or Fueld Return because I have 95 yes?
Yes to both you will have to buy a blow off valve plate and weld it into your piping.

12:1 FMU [special install for '95] (FMU IS THE SAME AS FPR CORRECT?)

Nope.

Oil Catch Can (Can someone explain more? Specific kind?)

PCV block off plate (Can someone please explain what this is and it's purpose?)

You don't need a catch can but this is where there is a few different ways of doing things. I will try to explain this but it might be hard to do without pictures. When ever your cylinder fires there is a little bit of gas that makes it by the cylinder and into the crankcase. That is called blow by. This gas needs to be vented so it doesn't build up pressure so there is a tube in our valve cover that goes to the intake manifold. Now when you add a turbo your intake manifold now has possitive pressure in it and you don't want to loose that into your valve cover so what a lot of people do is put a little breather filter on their valve cover and block off the intake side. Now when that blow by vents out the valve cover its usually dirty and oily so instead of running a breather filter people will buy/build their own catch can to catch the oil before it gets to the filter.
 
http://www.dsmtuners.com/forums/420a-turbo-conversion/339520-95-fmu-install.html





You don't need a catch can but this is where there is a few different ways of doing things. I will try to explain this but it might be hard to do without pictures. When ever your cylinder fires there is a little bit of gas that makes it by the cylinder and into the crankcase. That is called blow by. This gas needs to be vented so it doesn't build up pressure so there is a tube in our valve cover that goes to the intake manifold. Now when you add a turbo your intake manifold now has possitive pressure in it and you don't want to loose that into your valve cover so what a lot of people do is put a little breather filter on their valve cover and block off the intake side. Now when that blow by vents out the valve cover its usually dirty and oily so instead of running a breather filter people will buy/build their own catch can to catch the oil before it gets to the filter.


I think I undertand what you are saying, the one above the "D" on the cover needs the catch can on it.

And can someone explain the FPR, because now im lost again WTF I need to modify my stock one?
 
A good condition stock fuel pressure regulator works fine with the walbro, if yours is over run by it you will need a new one. Iirc, its 93 bucks for the part at autozone and other competitors.
 
A good condition stock fuel pressure regulator works fine with the walbro, if yours is over run by it you will need a new one. Iirc, its 93 bucks for the part at autozone and other competitors.

the fpr or block off plate?
 
I have never heard of a pcv block off plate because it cannot be a plated the line that goes from your valve cover to your intake manifold somewhere on it is the pcv valve they might have meant egr block off plate which is not necessary to boost, but the pcv valve is pretty important it releases pressure into the intake from the head.. getting rid of the pcv vavle will allow pressure from the intake to enter the head(where its not exactly wanted) this is my understanding of it its pretty much like a one way check valve.. but my point is that it is in-line and no plate can attach in-line
 
I have never heard of a pcv block off plate because it cannot be a plated the line that goes from your valve cover to your intake manifold somewhere on it is the pcv valve they might have meant egr block off plate which is not necessary to boost, but the pcv valve is pretty important it releases pressure into the intake from the head.. getting rid of the pcv vavle will allow pressure from the intake to enter the head(where its not exactly wanted) this is my understanding of it its pretty much like a one way check valve.. but my point is that it is in-line and no plate can attach in-line

the oil catch can goes on this line correct?
 
It is possible. But like necroposy mentioned. turboing a engine with high miles can lead to some problems later down the road. i have a n/t eclipse and that was my plan as well. The more research i did on it, the more i became turned off with the idea. There is just so much that is involved in that process. Than i found a gsx for 1500 that needed brakes and a few minor things :hellyeah: If you do decide you want to go through with this process. keep me posted. i have so much information saved on my computer i would be more than willing to share with you. A nice wish list of a full build. If you have any other questions feel free to ask. As much as i would side against the idea now. Its your car to do what you want with. ill help as needed. Good luck man. Keep us posted on whats going on with it. would love to see pictures also :thumb:
 
It is possible. But like necroposy mentioned. turboing a engine with high miles can lead to some problems later down the road. i have a n/t eclipse and that was my plan as well. The more research i did on it, the more i became turned off with the idea. There is just so much that is involved in that process. Than i found a gsx for 1500 that needed brakes and a few minor things :hellyeah: If you do decide you want to go through with this process. keep me posted. i have so much information saved on my computer i would be more than willing to share with you. A nice wish list of a full build. If you have any other questions feel free to ask. As much as i would side against the idea now. Its your car to do what you want with. ill help as needed. Good luck man. Keep us posted on whats going on with it. would love to see pictures also :thumb:


I'm for sure going through with it, I'm gonna hav to rebuild the engine anyways to increase boost and the fact it's old. I think I've got most of it figured out, but more help would b great
 
the oil catch can goes on this line correct?

yes this is the line the oil catch can goes on. I built my turbo kit from scratch some parts are ok off ebay not all i found that out fairly quick but I was the test subject for my other friends. one thing I learned from the 4 ish years of research is that expect Everything to go wrong and be sure to add that into your budget I believe I went through at least 3 oil Feed lines and 3 oil drain to stop many leaks and busted lines those are not very good to attain from ebay and to start off look for like a t25 turbo off craigslist they go for an easy 65. and check out treadstone performance they have good quality stuff and great service, CI Motorsports as well they usually have lower prices but take Forever to ship. My motor has around 110k and I boosted it at like 90k 7psi (I stayed on the safe side) your list of parts will change dramatically as you do more research i have two of the missing links I have a 96 eclipse and I did not see any difference other than my idle was rough. If you have any specific questions no matter how stupid they sound someone has an answer.

I also noticed that you are automatic I am unaware if you have a transmission fluid cooler or not but that should also be a thought to consider dont want that to over heat that will cost you more than a motor to repair. a universal such as derale off ebay should be a good bet
 
I'm for sure going through with it, I'm gonna hav to rebuild the engine anyways to increase boost and the fact it's old. I think I've got most of it figured out, but more help would b great

ya sure. anytime you have a question feel free to ask. if you want add me on here to make it easier for you in the future.
 
yes this is the line the oil catch can goes on. I built my turbo kit from scratch some parts are ok off ebay not all i found that out fairly quick but I was the test subject for my other friends. one thing I learned from the 4 ish years of research is that expect Everything to go wrong and be sure to add that into your budget I believe I went through at least 3 oil Feed lines and 3 oil drain to stop many leaks and busted lines those are not very good to attain from ebay and to start off look for like a t25 turbo off craigslist they go for an easy 65. and check out treadstone performance they have good quality stuff and great service, CI Motorsports as well they usually have lower prices but take Forever to ship. My motor has around 110k and I boosted it at like 90k 7psi (I stayed on the safe side) your list of parts will change dramatically as you do more research i have two of the missing links I have a 96 eclipse and I did not see any difference other than my idle was rough. If you have any specific questions no matter how stupid they sound someone has an answer.

I also noticed that you are automatic I am unaware if you have a transmission fluid cooler or not but that should also be a thought to consider dont want that to over heat that will cost you more than a motor to repair. a universal such as derale off ebay should be a good bet


I think im already starting to have transmission problems :banghead: :cry:
 
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