Evo 4 Slower after Upgrades?
Oct 3, 2018, 08:30 PM
#1
Newbie
Thread Starter
Join Date: Aug 2018
Location: Vancouver BC
Posts: 13
Likes: 0
Received 0 Likes
on
0 Posts
Evo 4 Slower after Upgrades?
Hello everyone.
So I bought and evo 6 Ecu and Injectors and found a shop with a great record that specializes in Evo's and Supras, so I thought I'd finally get my evo 4 re mapped. While it was there I had my tuner do some other small work as well, he swapped the stock turbo for an evo 6 turbo, relocated the battery and installed evo 8 style cold air intake, installed 3 port boost solenoid and raised boost, installed a Y pipe on a switch so I can be obnoxious when I want to, and then of course the injectors and street tune. I'm obviously didn't expect the car to feel like I just built the engine and got a huge turbo and be insane or anything, but it feels very noticeably slower? At first I thought it was just me, but I didn't even say anything about how I thought it was slower and everyone who has ridden in my car before and after has said to me "is it only me or is the car slower?". I'm also having trouble keeping up with some friends I used to drive with before and had no issues keeping up with.
I have some ideas but I wanna hear what you guys think it could be. My boost gauge is reading rougly 14psi on average driving normally, and I peak at 20psi. My first thought is boost leak potentially, which I will test for, but my tuner said if that was the case the car would be bucking? Then I thought maybe it's not getting enough fuel? Or the stock plastic blow off valve is not holding boost, or maybe wastegate stuck open? (I have checked, the waste gate seems fine and completely shut close and extremely little play in the flapper).
I'm taking it to my tuner not this coming weekend but the next and he said he'd take it out for a drive and log it to see if he can spot anything. Anything you guys would think it is that I should ask him to look at specifically or that I can check myself?
So I bought and evo 6 Ecu and Injectors and found a shop with a great record that specializes in Evo's and Supras, so I thought I'd finally get my evo 4 re mapped. While it was there I had my tuner do some other small work as well, he swapped the stock turbo for an evo 6 turbo, relocated the battery and installed evo 8 style cold air intake, installed 3 port boost solenoid and raised boost, installed a Y pipe on a switch so I can be obnoxious when I want to, and then of course the injectors and street tune. I'm obviously didn't expect the car to feel like I just built the engine and got a huge turbo and be insane or anything, but it feels very noticeably slower? At first I thought it was just me, but I didn't even say anything about how I thought it was slower and everyone who has ridden in my car before and after has said to me "is it only me or is the car slower?". I'm also having trouble keeping up with some friends I used to drive with before and had no issues keeping up with.
I have some ideas but I wanna hear what you guys think it could be. My boost gauge is reading rougly 14psi on average driving normally, and I peak at 20psi. My first thought is boost leak potentially, which I will test for, but my tuner said if that was the case the car would be bucking? Then I thought maybe it's not getting enough fuel? Or the stock plastic blow off valve is not holding boost, or maybe wastegate stuck open? (I have checked, the waste gate seems fine and completely shut close and extremely little play in the flapper).
I'm taking it to my tuner not this coming weekend but the next and he said he'd take it out for a drive and log it to see if he can spot anything. Anything you guys would think it is that I should ask him to look at specifically or that I can check myself?
Oct 4, 2018, 08:23 AM
#2
So, did you use to peak at 20 PSI and now only hit 14 PSI? If so, you probably have a boost leak or a problem with the Evo 6 turbo, wastegate, tune, or all the above. Are you able to monitor your AFR? I would definitely take it back to your tuner and have them fix it if it is tune related, but could very well be a mechanical problem. How is your tuner remapping your car? ECUflash?