EA82T Head to Turbo 'Power Pipe' Upgrade

discopotato03 · Post by **discopotato03** » Mon Apr 09, 2007 12:14 pm

Will be watching this space . I have to agree that the std header is hardly ideal but would have been a compromise from the factory to do with manufacturing cost and convenience plus long term support for the turbo . I doubt Subaru were looking for serious performance from the EA82T at that time or it would have been better .

From a gas flow point of view its pointless having the pipe size appreciably larger than the port size because its just unnecessary volume for the exhaust gas to pressurise betwen the exhaust valves and the turbo . The best collector will be a "merged" one of around 8 inches length . The collector pipe does not need to be huge because don't forget only one cylinder is exhausting at a time and you want to keep velocity up with minimul restriction .
Forget about scavange with turbo engines because with properly speced turbos its not the drama it used to be . Pretty hard to make a manifold promote scavange when theres a turbine in its path .

Secret weapon turbo . The best are generally the better thought out Garrett GT ball bearing turbos and the slowly growing twin scroll hybrids secret make it possible to have power and torque numbers in Hp and ft/lbs about the same and not using moonshot revs .
I'd reckon around 180-190 responsive Hp and ft/lbs would make an RX Turbo embarass many a brap brapping WRX .

We shall see , cheers Adrian DP03 .

stinky · Post by **stinky** » Mon Apr 09, 2007 12:51 pm

How's this going Justin? Any news ?

Xtreme_RX · Post by **Xtreme_RX** » Tue Apr 10, 2007 8:44 am

The exhaust shop pushed me back because of Easter. Next week it goes to them.

discopotato03 · Post by **discopotato03** » Thu Apr 26, 2007 5:45 pm

After a bit of research I reckon that the twin scroll IHI ball bearing turbos are more convienent to use because of their propper twinned wastegate flat valves . Subaru are getting great numbers out of their EJ20's with turbos like the VF38 and its great to think that all thats basically required to fit them is a modified twin up pipe and down pipe . Plumb oil/air/water and get good results with good tuning .

Cheers .

julian · Post by **julian** » Wed May 09, 2007 12:25 pm

Been exactly 1 month since your last post Justin, any news?

Xtreme_RX · Post by **Xtreme_RX** » Wed May 09, 2007 2:54 pm

I've been moved to another store & it’s difficult to get to the exhaust shop + my other car just spat its auto gearbox. So I have no car if I send mine to the shop......

As soon as I get another gear box for my other car I will have the pipes fabed up in a couple of days...

schultzie · Post by **schultzie** » Mon May 28, 2007 6:47 pm

and how is it going...

i think i will more than likely be going down this track in around a month.... so i might also have stuff to post up will be talking to exhaust places soon enough ,

julian · Post by **julian** » Sun Jun 17, 2007 2:54 pm

Anyone made any progress on this topic recently?

schultzie · Post by **schultzie** » Sun Jun 17, 2007 4:26 pm

car will be going down in the next week or so, i wil get them to look at it and if they can inprove on it then away we go and if not then at least we know, i got delayed because i decided to put the highflow turbo on and i have some vacume noise coing from it, all sussed now just need to get the car down there and then get a ride to work and much the same to get it home again

schultzie · Post by **schultzie** » Tue Jun 26, 2007 7:13 pm

well i got my Lseries back last week from getting my exhaust fixed, it was suggested that increacing the size is not nessairy unless we are all willing to loose out on torque, due to the size of thew motor, improving the tpiece would be a good idea but he did my seem to think that the money that would be spent to change what would be worth it,

maby he diddnt want to do the work but the guy is a respected exhaust bloke and well known and i dont think he woul dbe out to make me waste my money if he diddnt see fit, i told him of the mods and what sort of figures i am after and he still thought that the stock ones would do the job, well at least this way we wont be coming on boost later and have less torque,

on the other hand my highflow turbo that i bought over a year ago is definatly nice but the waste gate is to small for it now, so bugger where shoudl i go now

discopotato03 · Post by **discopotato03** » Wed Jun 27, 2007 12:16 pm

What is this "Hi Flow" turbo .

I think the best your going to get from an EA82T is with separate engine pipes from each head leading to twin up pipes and one of the IHI twin scroll ball bearing turbos ie a VF38 . They are designed to make low down torque which I think fits in with the EA82's lack of breathing abilities (ports) .

If you can lay your hands on the better factory cams ie late EA82 N/A and raise the static compression up a bit from 7.7 to say 9.0:1 , and a basic RS Liberty Water IC this is probably the economic limits of what you'd do to a road EA82 .

schultzie · Post by **schultzie** » Thu Jun 28, 2007 6:34 pm

the high flow is basically retaining the stock exhaust housing and making the compressor housing bigger and flow more air this also entails using a bigger compressor wheel, so basically i am coming on to boost earlyer and it will hold more boost for longer, i havent been able to give it a good run and watch it (tuning issues injector size... problems) but i have seen 22psi but that was not wanted... also i dont think my waste gate is working properly, but ill work it out,

i like the idea of the cams but do u think that the NA ones would not have a long enough exhaust lobe fo rthe extra fuel air mix?

discopotato03 · Post by **discopotato03** » Thu Jun 28, 2007 7:16 pm

The higher static compression EFI NA engines cams are longer duration than the turbos ones . Low compression ratio engines don't like longer cams because the dynamic or effective compression ratio (throttled petrol engine) gets unacceptably low meaning poor trapping efficiency and no guts off boost .

I think I'll look into more modern turbos because the larger compressor on std turbine is not without its drawbacks . I think the smaller IHI BB turbos could do a better job but I've not got that far yet . I have seen a pick of a turbine housing in the US that would mate a GT28BB based turbo to the Subaru up pipe but not sure if its in production yet .

Cheers A .

schultzie · Post by **schultzie** » Thu Jun 28, 2007 7:20 pm

yeah i know that there are probably better turbos out there, but with out going over board you will be wanting bigger injectors before you know it,

i picked this turbo up cheap it is in pretty good condition so im not complaining, and it stays on boost lots longer now so i personally think it is fairly well suited

agreed on that a newer turbo would be better but that aint going to happen so ill stick with wha ti have, injectors are next on my list, aparently 5th injector is not the way to go due to the complexity of tuning it so the motor runs right, ..

Xtreme_RX · Post by **Xtreme_RX** » Fri Jun 29, 2007 10:39 am

Update time......

I have just finished with the cad/paper drawings & i am happy with the outcome.

Should have a car at the exhaust shop in the next 3 or 4 weeks......

julian · Post by **julian** » Mon Sep 17, 2007 10:58 pm

Thought I would keep this thread alive and ask- Any news?
Been 10 weeks since last update...

Xtreme_RX · Post by **Xtreme_RX** » Tue Sep 18, 2007 7:54 am

The car is going to the exhaust shop today to get a final costing done...
And then next week I get one produced.......

stinky · Post by **stinky** » Tue Sep 18, 2007 8:00 am

woohoo! waiting with baited breath!

Xtreme_RX · Post by **Xtreme_RX** » Mon Sep 24, 2007 4:09 pm

DONE!!!

Photos to follow...

For those who are attending the Subaru 4WD Club meeting to night at Zupps you will get to see it fitted to my car......

Subafury · Post by **Subafury** » Mon Sep 24, 2007 8:25 pm

oo yeh and hows the power difference/spooltime?