4agte with no TVIS problems

[reecegze]

Hey guys ive got a 4agte that i am concerned about if there is any flow issues with the inlet manifold/head..

When i did the conversion i removed the TVIS plate and slapped on the TVIS inlet manifold straight onto my bigport 4agze with gaskets and plenty of silicone glue. I did this not knowing if you needed it or not.

Now the problem is i am fully setup now for the motor to make power. It makes 140kw on 13psi and 147kw on 16-17psi, boost holds nicely without any drops.

The motor isnt making any power even with more boost added, Tuner has suggested there is a flow issue causing motor to not flow the boost added.

So i am thinking its either my brand new I/C from ebay or my inlet manifold is not flowing like it should with out the TVIS plate "gutted". Maybe causing leaks out of the valley at High RPM?



Engine specs:

ae92 bigport DLI 8.1:0
Ems stinger 4424 v4
GT28rs disco potato brand new
300x280x60 intercooler with 2" piping
3" exhaust , hiflow cat
bigport cams
TVIS inlet bolted directly on head no TVIS plate/spacer
No boost leaks
motor been rebuilt recently 30k ish

Just after some ideas on what could be causing power issues and if i should gut the TVIS plate and fit it.


Thanks Reece

[slide86]

get TVIS plate......remove butterflies and refit. thats what i have done on my GZE

the manifold directly to the head isnt a 100% fit, there is potential for leaks at the mating surfaces, even with the gasket and what not.

and yes......only 7kw gain with an extra 4 pound is quite odd, specially with your setup

[Golberg]

And use the proper metal gaskets too.

Silicone sucks.

[biggo]

I actually port matched a 16v intake manifold when i went turbo.

Theres is more than enough meet in the manifold to grind down and get them to join befor the head.

[driftke70]

"engineers blue" is your friend

[s14seriesII]

i think klusio possibly had a similarish problem on his old setup.. but boost would drop at high rpm as the turbo exhaust was choking the motor
but i think 2 inch piping is maybe a tad small ish ?? there is no harm in going to bigger piping ( if you work out ho much air the engine is pumping at around 5000rpm the difference in volume of the i/c piping is not going to give a noticeable difference in on/off throttle boost response 2.5 inch is a nice size i wouldnt bother going any smaller

i have a question how can you state it has no boost leaks and yet you then turn around to ask maybe its leaking boost ? a boost leak is not going to show up as being a drop in manifold pressure.. the turbo will just pump more air so it maintains the same pressure..
but compressor efficiency will be greatly reduced

it could be weak valve springs giving issues, did the tuner say anything about injector duty or ignition timing ? sounds strange....
as an approxiamte rule you shouldnt take more than about 1 degrees timing out per psi of boost.. eg: 13 psi you have say 18 deg timing, on 16 to 17psi you should be around 15 to 14 maybe 13 deg timing any less and there is no point adding boost as you will not be making any more power only heat and make the boost gauge read higher

if it was an intercooler internal flow issue or similar. boost would drop off as the rpm rises.. is the intercooler efficient ? intake air temps before and after ? also its good to measure pressure at the compressor housing and compare it to the inlet manifold pressure this will show up any poor flow of the system

maybe some more information is needed ?

[AE86 Spoontah]

I mated my GE RWD intake straight up to my AW11 GZE head without TVIS plate. Checked port issues using GZE metal gasket and GE metal gasket and they were exactly the same apart from GZE having four ports and GE having eight ports. Ended up using four port metal gasket with RTV high temp silicone and have had no issues.

[reecegze]

How did your mate fix the chokin problem? I pressure tested the piping up to the t/b so I no there is no boost issues pre intake , I am gona spray can't cleaner around the manni on Friday to see if there is any leaks. I may upgrade the post ic piping to 2.5" later on. When it was dynoed it was 36degrees ambient with 75degree inlet temps.

The motor pumps out good a/f with alot of advanced timing up to 22 advanced with timing retards on higher inlet temps. The cooler is some eBay generic meant to flow 400hp.

Let us no how that other member went

cheers

[s14seriesII]

he took everything off and sold it.. pretty sure it was just the exhaust housing on his turbo that was the major restriction

75 deg inlet temps is very high.. whats it get too when on the highway under full load ?

[reecegze]

On the day it got tuned it got up to 82degrees haven't checked normal ambient days. Like I said it was tuned on a 40degree day