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1.8T Spool

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3.6K views 31 replies 9 participants last post by  susiemk  
#1 · (Edited)
What turbo are you using & at what RPMs do you get
1. Boost
2. Full Boost
On your 1.8l turbo conversion in 1st gear (no launch)?

I'm thinking about another Ghetto turbo, a 1.8l this time using a VF11 but do not want to have something that is ALWAYS in boost....
 
#3 ·
OK so in 3rd gear 5psi is there from 2500RPMs on @ WOT, but how quickly or slowly does it spool in first gear - I actually want something thats sorta laggy so that its not constantly boosting on HW cruise.
 
#4 ·
hmm, well i sit around 3000-4000 on the highway with 3.9(stock 5 spd L) gearing and a td04. i would make a quick video of me just crusing on the highway but my cars down. you could run fmic to induce lag. Another option is get a dual stage mbc or ebc. I have one setting at wastegate andd one at 17psi. Flip the switch and youre running 5-6 psi, need to get on it alot?:)D), flip it to 17
 
#5 ·
I was gonna actually go for the low boost high compression combo as I'm not trying to rip anything apart!

I actually did a how to on the 2 stage/Level MBC using a charcoal canister purge solenoid, switch & MBC on Legacy Central a WHILE back but I do not plan on running more than 5-6 psi as this car is really just a little run-about.

I paln on using Methanol injection + a stock ej22t plastic charge tube to keep the Wagon as low key as possible - no scoops or I/C cores visible
BUT
When I FMIC'd my Legacy SS on the VF11 there was no additional lag - boost was INSTANT - that engine was 20% bigger than the 1.8l so funny as it may sound I hope the little engine = more lag...

I'd be happy with boost onset @ about 1800-2000 rpms with max boost happening soon after, I just do not want boost onset @ 1000rpms with max boost @ 1500RPMs like the VF11 does on the 2.2ls.
 
#7 ·
Well the little VF11 was able to hold 10psi on my ej22t SS until redline - I never tried to push it further than that as it was enough & bigger turbos where on there way.
I think they start to taper off after 4500RPMs once you pass 12psi on the 2.2ls but can't say for sure.

I EJ20G'd the car & was on a TD04 for a while & ran about 14-15psi until redline with a 19psi spike @ low RPMS & am now on a ported TD05 / EL headers @ 13-17psi with accidental 19-20psi runs happening every now & then.

I actually lowered boost to 13psi recently because the tranny (4eat) is still stock as I have not had a chance to get the v-body modded or install my high stall t-converter or manual shift box - so the lower High boost leve lkeeps everything happy with the tranny...
 
#12 · (Edited)
On your 1.8l turbo conversion in 1st gear (no launch)?
The 1st gear ratio on the FWD 1.8L are the same on the STI. You get to redline so fast, next thing you know, you're in 3rd gear. I've reached up to 18psi at the highest when messing with boost duty cycles, lots of tire spinning. Its perfect right now at 16psi. I'll never see 20psi in 1st, something WILL break.

on my ported td04 ej18 with 2.2 heads and a fmic i was gettin it at 3500
How did it go for you on teh VF39?
 
#17 ·
I want to know when a 1.8l starts to boost in a low gear (slower boost response) to estimate how easily is will be to keep the car OUT of boost on HW cruise.

Strange that you get no boost in 1st on your car as I get about 11.5psi of boost @ about 3k in 1st on my Phase II OBS-t with no launch - it pulls 4th like 2nd :).
 
#18 ·
When I can't take the lack of HP & do the conversion I think I'll start off with a VF11 since it will be EASY to get everything connected up with & they are a CHEAP option for folks that would like to do this conversion thmeselves & if response is too quick for my needs I'll plop on a TD04.
 
#19 ·
I think the TD04 will be the best option for you. Its not too small and quick as the IHI VF11 yet, not as laggy as the IHI RHF55 compressor VF turbos. Its a good balance within all three types of turbos. You can try finding a ball bearing IHI VF23 that has the P18 housing and a smaller RHF5 compressor housing (similar to TD04). That turbo would fall between the TD04 and RHF55 VF turbos, good balance between response and power.
 
#20 ·
Yeah I think the VF23 would be perfect for a high boost 1.8T like yours but my eventual 1.8t set-up will be low boost highish compression.

I also would like to keep this super low budget so other folks can do this too so the TD04 sounds perfect.
I'll still probably try the VF11 out just to see if 20% less displacement will give 20% slower spool.
 
#23 ·
But I'm not running a big turbo, it's a GT24 or GT25, whatever comes with the AVO kit. I routinely run at vac, and get 28-29 MPG over a tank of gas. I'm thinking that the reason the ej22t is constantly running at 0 or + pressure has to do with it being connected to an automatic, maybe, but I don't know. I have a friend who has a Nissan 240SX with an RB20DET swap, and he upgraded to a big turbo, and he's not driving around at + pressure until he romps on the gas, either. Just seems that under light throttle while cruising, no turbo should be making boost, unless it's a really tiny turbo that is undersized for the application. And a bigger turbo will be even less likely to make boost at light-throttle cruise due to the lag in it.
 
#25 ·
That's probably why it's spooling and making boost at highway cruise, it's way too small for the application. Size it correctly, and you can have it all, like I do on the AVO kit: no boost under cruise, but quick spool with full boost very early. You can figure that all out from a compressor map... if you're Stephen Hawking! Well, maybe not that smart, but I have no idea how to read those things.
 
#27 ·
You guys are making me want a 1.8T project, too bad I just tore down the sedan for swappage.

I was going to go with the crossmember swap and therefore OEM turbo manifold, HKS up and down pipes with this TD04 I've got sitting around, with a FMIC. But not anymore, so if anyone wants some spare EJ18 parts soon, holla

but regarding the lil' turbo discussion, the I had that TD04 on my desk at work one day, everyone was making comments about how my turbo is so small :( :lol:
 
#29 ·
Hmm yea cuz my td04 on this 2.5 L is only in boost when I hit the gas, crusing around she sits below -10 to -17 on the gauge. Great when you want boost beacuse it is instant.

I just got a tune and the gas mileage was way better than being N/A, with the tune and more fuel up top it will be interesting to see the change.
 
#30 · (Edited)
It is funny how gas mileage can improve with a turbo.
Same thing happened to my OBS-t.

Turbo options for me include the VF11 (1st choice), JDM 90* inlet TD04 2nd choice, US TD04L 3rd choice, VF30 last choice.
I'm pretty sure I can get the JDM TD04 to work with the TD04 using a silicon 45* connector which will get it on the car wil no fuss.