T-vis Or Non T-vis

[Gti-Racing]

My Last corolla gti had the T-vis and this doesnt, however the last one was a little quicker to 60, and revved higher in each gear, i to be on the safe side only took it 1st - 30mph

2nd - 60mph

3rd - 90mph

4th - 120mph

5th - 133mph

and that was around 6,800rpm

This non t-vis struggles with 60 in 2nd, definatly cant do 120 in 4th

SOOOO i was thinking about replacing my non-T-vis with a T-vis, any imput anyone?? as i was wondering if i did this would i need to replace my ecu as it might not be programmed for T-vis

thanks

[Twincam.GTi]

Gti-Racing Posted Yesterday, 02:06 PM

  My Last corolla gti had the T-vis and this doesnt, however the last one was a little quicker to 60, and revved higher in each gear, i to be on the safe side only took it 1st - 30mph

2nd - 60mph

3rd - 90mph

4th - 120mph

5th - 133mph

and that was around 6,800rpm

This non t-vis struggles with 60 in 2nd, definatly cant do 120 in 4th

SOOOO i was thinking about replacing my non-T-vis with a T-vis, any imput anyone?? as i was wondering if i did this would i need to replace my ecu as it might not be programmed for T-vis

thanks

Yes the earlier AE92 GTi (1987- mid 1990ish) had T-VIS (like my '89 example) and the later ones (late 90 to 1992) didn't. Personnally I to find that the 'T-VIS' version is quicker, yet according to the official Toyota Data/Spec information non T-VIS (1990 onwards) are faster all round and have slightly more bhp!

...so normally I find it best to keep my mouth shut on which version is faster (but glad someone else has now discovered what I have said in the past)

[L4AGZE]

I have owned both TVIS and non TVIS GTi's and there is not much between them. My first GTi was a TVIS example and had a cracking engine, to this day i have not driven another GTI with anywhere near as good an engine or as powerful. If i had known it at the time I would have kept the engine!

The TVIS engines have a larger intake port and as it utilises the TVIS system it appears to 'kick' more when you press the car hard. I think these days in the Tsports its referred to as 'lift' but that is a different system.

The non TVIS engines actually have a stronger block and for this reason many people say go for the non TVIS especially if your going to be modifying the engine.

If you put a non TVIS and TVIS side by side on the track I dont think there would be much if any difference between the performance (engine condition aside) but I do think the TVIS feels quicker although doesnt rev as high as the non TVIS.

If you were to replace the engine you would have to replace the ECU as im fairly certain the plugs are different so that means you would need the wiring loom too. In my opinion it wouldnt be worth carrying out the transplant rather spend the money on your current engine, its amazing what a rebuild can do!

[Gti-Racing]

WICCKKKEEDDD!!! im sooo glad some people agree with me, in that Tvis's are better then non-Tvis, i also found them to be more economical, i once did 130miles on 7.00 and around 70% motorway and the rest street driving, and i was doing around 80mph on motorway

but i read this thing about the t-vis and it said that it had variable timing, and also had a bigger port,

L4agze i wasnt thinking of changing the engine, just the air unit, if i did this would i need to change the ecu is what i asked???

i thought the last car revved higher, although i rarely had to take it that high as i was getting high speeds in around 6.8rpm

but can anyone answer that question???

(about having to change ecu along with change from non-t-vis to t-vis)

[JT]

i can't answer the ecu question, but you say this...

but i read this thing about the t-vis and it said that it had variable timing, and also had a bigger port,

it doesn't have vvt. (to the best of my knowledge) it has 2 sets of throttle butterflies, the 2nd set of which only open under high load conditions, or after about 5000rpm - that's why it seems to pick up around there.

if you do rebuild, one option (if you want to keep the TVIS) is to use the stronger bottom end from the non-TVIS block and the TVIS top end. as far as i know, this is what my car has

[Twincam.GTi]

JT Posted Today, 03:35 PM

if you do rebuild, one option (if you want to keep the TVIS) is to use the stronger bottom end from the non-TVIS block and the TVIS top end. as far as i know, this is what my car has

Truely the best of 'both worlds' , makes you wounder why Toyota didn't adopt this route.

[Treuno]

Well some of the coments made of engines revving higher than others is incorrect! All 16v 4AGE's rev to the same rpm, but the peak power is higher up the rev range on the non TVIS engine!

I rev my TVIS AE82 to 7700rpm every gear change even though the peak power is around 6500! But to rev it to 7700 helps the engine for the next gear so it doesnt have to pull so hard from lower revs!

Toyota didnt fit the stronger block to the early cars as that block was only designed after Toyota done long and hard tests with the Weaker block to find that it flexed!!!!! And dont forget it isnt just a stronger block, but the crank journals are bigger as are the gudgeon pins and the block also has oil spray pipes to the bottom of the piston skirts!

This flex etc eventually gave big end failure etc! So im sure that if Toyota new that info in 1984 when the first 4AGE was released im sure they would of! :D

I had to put the stronger block in JT's corolla due to when i owned it the original bottom end failed! I think it may have been due to faulty oil pump but then again it may have just been the weaker block saying ive had enough! :(

But if your talking 20v 4AGE's then that is a different kettle of fish! What an awesome engine that is and this engine does have VVT!!

[System~G]

All I can say is my AE92 with the late spec Non-TVIS engine felt A LOT quicker than my MKI MR2 with the very early blue top engine.

Granted it's only been running on 3.25 cylinders since I've owned it. I will be able to give a propper evaluation later this weekend once my engine swap is completed. (Putting in a later version red top TVIS)

[L4AGZE]

Treuno, I actually meant the non TVIS makes its peak power higher up the rev range but did not explain myself well.

As for the engine in the MR2 I think the newer spec engine will make a difference obviously as your current engine isnt running on 4 cylinders, but isnt the MR2 a heavier car? It would feel slower than a Corolla with the same engine in due to the difference in weight and if its T bar that makes it even heavier. Amazing what weight savings can do to performance.

As for the strength of the block even the 'weaker' block is very strong as it rarely goes wrong but then Toyota do pride themselves on being super reliable so it made sense for them to strenghten it.

As for the original question i would think if you were to fit the TVIS system you would need to change the ECU or make some adaptations to the wiring as there are differences between the the two ECU's. I still dont think the cost would justify the end result but could be proved wrong!

[Treuno]

Ah i see! No worries then mate! ;)

But i dont agree that the MR2 is heavier!? Its alot smaller than the corolla! Im gonna have to find some weight figures!

I personally wouldnt bother to go to the TVIS system if you already run non TVIS! Waste of time and wont prove hardly any performance difference!

When people say....... my tvis was quicker than the non tvis etc it could simply be that one of the engines is coked up more than the other and not set up as good e.g. timing/emmisions etc!

Its amazing what a good decoke and tune up will do!

Some genuine figures:

[Gti-Racing]

yeah i suppose you guys whove said its not worth the cost compared to power gains for the tvis swap, im not guna do that no more, im looking to get the dastek unichip next anyways

and about engine rebuilding, mate i cant afford to eat, never mind this bit off this engine, and that bit off that, id need to buy 3-4 engines , hehehe, but i think the unichip would be the best thing for me

my tvis had a hole the size of an Apple on the bottom end as the water ran out and i was doing at around 110mph,

but thanks for all the advice guys,

what mods would you guys recommend to get good power gains for not too expensive (eg my dastek is guna cost me 380 mapped and fitted) similar costs to this, im aware of the rawengineereing conversion from 129hp - 160hp for 895.00

but any other little things youve done and noticed gains??

[andy_twincams]

what mods would you guys recommend to get good power gains for not too expensive (eg my dastek is guna cost me 380 mapped and fitted) similar costs to this, im aware of the rawengineereing conversion from 129hp - 160hp for 895.00

you could get it down by doing the work your self(only if you can??) cams £320 ish fse boost valve 120 ish.then mabye a manifold and port and polish and it would pull like a beast

[Gti-Racing]

Ive heard that cams actually slow you down in the bottom end of the rev range and pull HARD towards the top, and FSE Fuel regulator is supposed to not give any power at all, just increses pressure in the fuel rail, as the injectors are still 250cc, but im not 100% in what i say, any 2nd opinion on the FSE??? (not to say that i dont take your word for it andy, just that a 2nd opinion solidifies things)

[Uncle GXi]

My Last corolla gti had the T-vis and this doesnt, however the last one was a little quicker to 60, and revved higher in each gear, i to be on the safe side only took it 1st - 30mph

2nd - 60mph

3rd - 90mph

4th - 120mph

5th - 133mph

and that was around 6,800rpm

This non t-vis struggles with 60 in 2nd, definatly cant do 120 in 4th

SOOOO i was thinking about replacing my non-T-vis with a T-vis, any imput anyone?? as i was wondering if i did this would i need to replace my ecu as it might not be programmed for T-vis

thanks

←

Right, I've probably missed out on this discussion now, but here it goes anyway! I've had both TVIS and non-TVIS versions of the Corolla GTi and I've found that the non-TVIS was quicker. Bearing in mind that the removal of TVIS wasn't the only change on the later spec engine. It also gained oil-sprayed piston skirts and a narrower port design on cylinder head (see Fensport for more info on this). Quoted power figures were 122BHP for the TVIS and 129BHP for the non-TVIS. However, both versions of the Corolla GTi were quoted with the same 0-60 of 8.3 secs.

In my opinion, it really seems to vary with each individual engine... Some days when I used to drive my '91 GTi it would seem sluggish and really strained. Other days it would absolutely fly. A similar situation with my '88 GTi too... Anyone else experienced this?

[JT]

In my opinion, it really seems to vary with each individual engine... Some days when I used to drive my '91 GTi it would seem sluggish and really strained. Other days it would absolutely fly. A similar situation with my '88 GTi too... Anyone else experienced this?

yes! im usually unsure whether it's just me, but it definitely seems faster some days than others. i noticed that with my last one too

[System~G]

As for the engine in the MR2 I think the newer spec engine will make a difference obviously as your current engine isnt running on 4 cylinders, but isnt the MR2 a heavier car?  It would feel slower than a Corolla with the same engine in due to the difference in weight and if its T bar that makes it even heavier. Amazing what weight savings can do to performance.

←

Still not got my MKI MR2 back... :( Needs a new sump fitting)

I don't know what the kerb weight of an AE92 is, but the MKI MR2 with a sun roof (like mine) & not T-Bar has a kerb weight of 1050kg. But I have also heard the earlier MKI's had a kerb weight of 980kg (don't know where the person got their figure from though)

I also have accelleration figures (from standstill) quoted as:

True MPH.......Time (secs)........Speedo MPH

30.................2.5.....................32

40.................4.0.....................43

50.................5.7.....................54

60.................7.7.....................65

70.................10.8...................75

80.................13.8...................87

90.................18.5...................99

100...............24.5...................110

110...............34.8...................121

120...............-----...................132

Standing 1/4mile: 16.0sec@86MPH

[rx7_guy]

hey there i got a 86 fx gt japan new with tvis and it also seems to me to be quicker on some days, although it has no power at all wen cold haha.

It also seems to have a problem that it often doesnt want to start sumtimes. wen the key is turned the engine just doesnt want to kick into life. also wen driving the engine has just cut out and i need to use the key to get it started again. ne1 gt ne ideas on this?

[nathanfreke]

Non t-vis is better. period. Much better head design & stronger internals.

[TOYMOTA]

Here's a quote:

First Generation 4AGE (83.5-87.5)

The first generation 4AGE was introduced in May 1983 and remained in production until May 1987. Engines can be roughly aged by the year printed on the spark plug leads – provided they are original. The engine is externally identified by silver cam covers with black and blue lettering, hence they are often referred to as 'blue and black tops'. This generation was produced in transverse form (AW 11 MR2 and AE 82 FWD Corolla) and RWD longitudinal from (AE 86 Corolla GT/Corolla Levin/Sprinter Trueno and AA 63 Celica). Transverse engines have the throttle body at the flywheel end of the inlet manifold while RWD have the inlet at the pulley end.

This generation features the Toyota Variable Intake System (TVIS), which is a set of four butterflies located in the inlet system next to the head. These butterflies remain shut below approximately 4500 RPM, effectively limiting airflow to one valve per cylinder, increasing the air speed and thus improving mid range torque. They are opened above this speed by the ECU via a small plastic vacuum tank and solenoid triggered actuator located under the inlet manifold. The feel is similar to a second throat opening on a carburettor. These engines develop in the vicinity of 88 kW in transverse configuration, but around 95 in some RWD models. I am not sure if this applies to all RWD models, or only those that do not run a factory exhaust sensor (such as the NZ new leaded petrol versions). RWD versions are all MAP sensored; some Japanese sourced transverse engines may be air flow meter equipped.

These engines have a weaker block and crank than later versions, and suffered from the crank pulley bolt coming loose, allowing the pulley to damage the crank and key way. Later model engines have a separate bolt and washer, whilst these first generation engines have an integral unit.

Second Generation 4AGE (87.5-89.5)

The second generation engines were released in May 1987 and are identified by silver cam covers with red and black writing, hence ‘red and black top’. Effectively these engines retained the previous head and TVIS, but employed an all new, stronger block (identified by seven vertical ribs as opposed to three on the 1st generation engines), heavier duty crank and conrods. These engines remained on the market until May 1989 and have similar performance to the first generation transverse models, but are more robust. These engines were only produced in FWD, hence all throttle bodies are located at the flywheel end of the engine.

A supercharged model (4AGZE) was also released. This engine has unpainted cam covers. The engine fitted to MR2s has the supercharger outlet to the intercooler facing the flywheel end of the engine block and a normal distributor. The model fitted to the FWD Trueno/Levin has the intercooler plumbing facing upwards (the intercooler mounts on top of the cam covers) and has a crank angle sensor fitted in place of the distributor. This engine is fitted with twin coil packs instead of a conventional distributor arrangement. Power output is 107 kW for both supercharged configurations.

All 2nd generation engines are equipped with an air flow meter and were fitted to AE 92 Corolla/Levin/Truenos and face-lifted AW 11 MR2s.

Third Generation 4AGE (89.5-91.6)

The next generation engines were introduced in May 1989 and remained in production until June 1991. These engines effectively retained the heavier duty block but added a new head with smaller intake ports, hence the TVIS was discontinued. Some engines have silver cam covers with red lettering only (and so are called red tops), while others continued with black and red lettering. The easiest way to identify these engines is by the ribbing on the top surface of the intake manifold (earlier models have smooth tops) and an external oil drain from the head to the sump, located on the inlet side behind #4 inlet port. The sump is slightly different to earlier models.

These engines all have oil cooled pistons and the ignition leads run underneath a cover between the cam covers. Power is increased to 100 kW and all engines are MAP sensored. I believe these engines all feature a knock sensor, located near the top of the block on the inlet side between #2 and #3 cylinders. This is the final naturally aspirated 16 valve variant produced.

The 4AGZE has the same additions and utilises the twin coil distributor less ignition system, as it was only available in FWD AE 92 Levins and Truenos. Power increased to 120 kW and the supercharger has a smaller diameter pulley compared to the earlier version.

Loads more info here guys. Especially near the bottom.

http://www.users.bigpond.com/vidore/toyota_4age_engine.htm

[Lauren]

I don't know what the kerb weight of an AE92 is, but the MKI MR2 with a sun roof (like mine) & not T-Bar has a kerb weight of 1050kg. But I have also heard the earlier MKI's had a kerb weight of 980kg (don't know where the person got their figure from though)

You are right the early MK1s are the lightest but they are still heavy cars at 1030kg (kerb weight of mine sans fuel). A t0bar SC incomparison weighs in at 1185kg!

Corollas are always going to be lighter as they have 3 bulkheads rather than the 5 of an MR2.