has anyone??? (removed TVIS)

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mong

has anyone??? (removed TVIS)

Post by mong »

simply removed the T-VIS setup on the 4-age engine????

does everything bolt back on after the spacer is removed???

many thanx

tony
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Lauren
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Re: has anyone??? (removed TVIS)

Post by Lauren »

there is no point.

It will only reduce low end torque and obviously make no difference at the top end.
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Re: has anyone??? (removed TVIS)

Post by MartG »

mong wrote:simply removed the T-VIS setup on the 4-age engine????



Toyota !

E.g. Corolla GTi from about H reg on didn't have a TVIS, and made about 130bhp
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Re: has anyone??? (removed TVIS)

Post by Lauren »

MartG wrote:
mong wrote:simply removed the T-VIS setup on the 4-age engine????



Toyota !

E.g. Corolla GTi from about H reg on didn't have a TVIS, and made about 130bhp


Yes that is true, but that is a different engine. the later engine is a small port design with raised compression ratio which is where it generates the extra power from. A small port head does not suffer the same issues with low down torque as gas velocity is kept relatively high at lower revs due to the ports being smaller.
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Re: has anyone??? (removed TVIS)

Post by kevin..in »

E.g. Corolla GTi from about H reg on didn't have a TVIS, and made about 130bhp
_________________
I've got this engine fitted Lauren has already explained the techy stuff. if you wanted to see what its like without you could find a way of locking the TVIS flaps open then you will see its not a good idea on your engine. it apparently kills the torque at low revs and does nothing extra above 4,500 so not good #-o had i read Laurens first post properly i would have seen she's already said that :oops:
Corolla GTi from about H reg
the AE92 non tvis small port engine was produced from may 89 to june 91
mong

Re: has anyone??? (removed TVIS)

Post by mong »

are yes this i understand as ive been buliding mazda inlet manifolds for a while now and they use a system called VRIS which does the exact same job!!!!

but!!!!!!!!!!!!!

both VRIS and T-VIS are restrictive and there are gains to be made at the top end if its matched with other mods!!!!

just tieing the valves open will not demonstrate what i need as the butterflies and other mechanical parts will still be present and restricting the air flow into the ports!!!

similar to the good old days of thinning down carb butterflies etc etc

also when 'on gas' there is the increased risk of the gases puddling on the wrong side of the unopened valves

if you are flowing more air than stock then T-vis will become costly to the top end ive proven this on a flow bench and are putting it into practice this weekend just wondering if anyone had any pointers before i went ahead!!!

thanx for your input

tony :wink:
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Lauren
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Re: has anyone??? (removed TVIS)

Post by Lauren »

mong wrote:are yes this i understand as ive been buliding mazda inlet manifolds for a while now and they use a system called VRIS which does the exact same job!!!!

but!!!!!!!!!!!!!

both VRIS and T-VIS are restrictive and there are gains to be made at the top end if its matched with other mods!!!!

just tieing the valves open will not demonstrate what i need as the butterflies and other mechanical parts will still be present and restricting the air flow into the ports!!!

similar to the good old days of thinning down carb butterflies etc etc

also when 'on gas' there is the increased risk of the gases puddling on the wrong side of the unopened valves

if you are flowing more air than stock then T-vis will become costly to the top end ive proven this on a flow bench and are putting it into practice this weekend just wondering if anyone had any pointers before i went ahead!!!

thanx for your input

tony :wink:


It might be worth remembering Tony, that the ports are too big on the early engine to start with so i doubt there is going to be a significant restriction at higher revs. What are you trying to acheive with the engine?
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Read the stuff on the site below

Post by j0nathan »

Hi,

I have been trawling the web for a while and reading lots of information regarding removing TVIS, turbo charging the 4AGE, general tuning and so on. The below site may help you:
http://www.billzilla.org/carindex.htm

HTH,
Jon
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Re: has anyone??? (removed TVIS)

Post by kevin..in »

just tieing the valves open will not demonstrate what i need as the butterflies and other mechanical parts will still be present and restricting the air flow into the ports!!!
this was just a suggestion to quickly demonstrate the negative effect it would have on bottom end torque. Bill Sherwood does recomend removing Tvis on more highly tuned engines though
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TVIS mods

Post by JMR_AW11 »

If you completely remove the TVIS bits and alter the airflow you may confuse the engine management. Anything you change downstream of the throttle body will affect a speed density system. This is because it affects the volumetric efficiency of the engine for a given rpm and MAP sensor reading. This will affect both the mixture and ignition timing.

Ideally you should remap a speed density system for fuel and ignition after such changes.

I would agree with Lauren in that I too have heard that there would be little to gain from these TVIS changes on this engine.
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Re: has anyone??? (removed TVIS)

Post by Lauren »

kevin..in wrote:
just tieing the valves open will not demonstrate what i need as the butterflies and other mechanical parts will still be present and restricting the air flow into the ports!!!
this was just a suggestion to quickly demonstrate the negative effect it would have on bottom end torque. Bill Sherwood does recomend removing Tvis on more highly tuned engines though


From the info i've gleaned so far about the 4AGE it seems the small port engine is the better one for high end NA tuning. So i'd say if you are going to those lengths start off with an AE92 (with assorted AE101 components) and ditch the large port engine.
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Re: has anyone??? (removed TVIS)

Post by kevin..in »

totaly agree and if you want one I was offered a complete ae92 car for virtually no money only a couple of weeks ago, it maybe still available :idea:
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Re: has anyone??? (removed TVIS)

Post by Lauren »

kevin..in wrote:totaly agree and if you want one I was offered a complete ae92 car for virtually no money only a couple of weeks ago, it maybe still available :idea:


I would like to play around, but need to leave things as is for the time being. For some reason i keep hoping some cheap cams will pop up somewhere.. ;)
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Re: has anyone??? (removed TVIS)

Post by kevin..in »

I would like to play around
:shock: :shock: hopefully we are still talking cars :? I fancy doing cams and a bit of porting but modding as you know is a rampant disease once you start it just goes on forever
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Re: has anyone??? (removed TVIS)

Post by Lauren »

kevin..in wrote:
I would like to play around
:shock: :shock: hopefully we are still talking cars :? I fancy doing cams and a bit of porting but modding as you know is a rampant disease once you start it just goes on forever


GLOL! Typical of me to do a faux pas, i'm just way too innocent. ;) Don't worry i'm happily (nearly) married!

Know what you mean about the whole modding thing. I spend thousands on my last two SCs and modded pretty much everything. Ended up with a pretty good car at the end of it though and it was very far removed from what a standard car is.

Now i've got bored with forced induction and realise the NA is the way forward i've been spending a bit of time on club4ag and AEU86.org as i'm obsessed with 86's and running a highly tuned 16v or possibly a 20v with high lift cams.

I've also heard that with an AE101 crank, AE92 rods that 9000rpm is fine. I must admit i do like the sound of that. I may though be looking for an AE92 spec'd engine in the next few months as i am fairly sure that my rings are going (well oil control) on my current engine, so was aiming at getting a spare to slot in. Of course would be nice if i can play with the spare for a bit.

I guess i could run an AE92 spec engine for the sake of simplicity with teh TVIS just so i don't need the later ecu etc.. and take advantage of the increased comp ratio and the stronger bottom end. Just wondering how well the early inlet manifold matches up to the AE92 head? Thing is to run an AE92 properly i'd need the ECU too.

Have you seen the toda racing stuff?:


Image

*RAWR* ;)
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Re: has anyone??? (removed TVIS)

Post by kevin..in »

Lauren my AE92 runs well on the Ae86/aw11 ECU I would like to get my hands on an AE92 ECU and am currently watching ebay like a hawk, the guy with the AE92 car for sale had the whole lot but I couldn't justify getting another car on the drive. If you want a 20 valve PM me for a contact no. for a complete levin front end clip :wink: Oh the inlet manifold do not interchange but I have see on Ebay.com an addapter plate in the USA so they must run AE92's with TVIS on!
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Re: has anyone??? (removed TVIS)

Post by Lauren »

kevin..in wrote:Lauren my AE92 runs well on the Ae86/aw11 ECU I would like to get my hands on an AE92 ECU and am currently watching ebay like a hawk, the guy with the AE92 car for sale had the whole lot but I couldn't justify getting another car on the drive. If you want a 20 valve PM me for a contact no. for a complete levin front end clip :wink: Oh the inlet manifold do not interchange but I have see on Ebay.com an addapter plate in the USA so they must run AE92's with TVIS on!


Yep i've seen the adaptor plate, basically matches the large port manifold to the small port head.

Tbh i'm not thinking of 20valving at this point, want to do that to an 86 at some point in the future.

So are you using TVIS or not? Am i right in thinking that you are running totally stock AE92 engine on AW11 ECU?
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Re: has anyone??? (removed TVIS)

Post by kevin..in »

stock ae92 engine with aw11 ecu runs fine exept for slight prob at about 1,000 - 1,200 revs but this is only noticeable in traffic and I never do traffic, i could just be a set up prob TPS maybe. had a though if you fancy a drive we could arrange it sometime I not promising its anything fantastic for me it was just a cheap solution to my engine problem but there is obviously more potential with this engine over the ae86 unit. returned 38.6MPG on the wales run over 280 miles so fueling not too far off I think
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Re: has anyone??? (removed TVIS)

Post by Mk1 Turbo Powered Steve »

Lauren wrote:
kevin..in wrote:
I would like to play around
:shock: :shock: hopefully we are still talking cars :? I fancy doing cams and a bit of porting but modding as you know is a rampant disease once you start it just goes on forever


GLOL! Typical of me to do a faux pas, i'm just way too innocent. ;) Don't worry i'm happily (nearly) married!

Know what you mean about the whole modding thing. I spend thousands on my last two SCs and modded pretty much everything. Ended up with a pretty good car at the end of it though and it was very far removed from what a standard car is.

Now i've got bored with forced induction and realise the NA is the way forward i've been spending a bit of time on club4ag and AEU86.org as i'm obsessed with 86's and running a highly tuned 16v or possibly a 20v with high lift cams.

I've also heard that with an AE101 crank, AE92 rods that 9000rpm is fine. I must admit i do like the sound of that. I may though be looking for an AE92 spec'd engine in the next few months as i am fairly sure that my rings are going (well oil control) on my current engine, so was aiming at getting a spare to slot in. Of course would be nice if i can play with the spare for a bit.

I guess i could run an AE92 spec engine for the sake of simplicity with teh TVIS just so i don't need the later ecu etc.. and take advantage of the increased comp ratio and the stronger bottom end. Just wondering how well the early inlet manifold matches up to the AE92 head? Thing is to run an AE92 properly i'd need the ECU too.

Have you seen the toda racing stuff?:


Image

*RAWR* ;)

Sorry to hear about the engine Lauren.Was a great engine while i
had it!
:( :(
I'm sure you will get it sorted!! :D
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Re: has anyone??? (removed TVIS)

Post by Lauren »

[quote="kevin..in"]stock ae92 engine with aw11 ecu runs fine exept for slight prob at about 1,000 - 1,200 revs but this is only noticeable in traffic and I never do traffic, i could just be a set up prob TPS maybe. had a though if you fancy a drive we could arrange it sometime I not promising its anything fantastic for me it was just a cheap solution to my engine problem but there is obviously more potential with this engine over the ae86 unit. returned 38.6MPG on the wales run over 280 miles so fueling not too far off I think[/quote

Cheers for that Kevin, I think i can imagine that the difference would be fairly subtle, but it would be interesting to see how it runs, because if i do get a replacement engine (i am sure i will need to eventually) then going AE92 spec would i think be the way to go.
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