59 replies to this topic

[Nev]

I'll put the A20NFT on my watch-list 

 

For turbo fitting issues... :  I put a turbo inc. 3" exhaust on my 2.2 N/A and it fits. So i reckon it should as well on a A20NFT.

 

 

Some pics of your car with engine + turbo + exhaust manifold + exhaust all installed would be interesting...

 

Edited by Nev, 07 March 2017 - 12:21 PM.

[siztenboots]

its not the cams profile, but the springs and hydraulic setup that means 7500 is a sensible limit on standard cams, until you go solid setup.

[Nev]

As Steve says, strong enough valve springs are important for higher revs to avoid valve float, though I'm not sure what the OEM springs can cope with TBH.

 

As a general rule, high lift + long duration cams (and wider valves) become more and more important as the RPM limit moves up. This is because the amount of time that they are open is reduced as RPM rises, thus it helps to increase the size of the gap that the charge is being shoved through.

 

On a negative note however, they can cause idling issues and a loss of torque at low RPM, depending on how extreme you go.

 

As we are talking about it, on the A20NFT the cam profile is dynamically modified to give you the best of both worlds.

Edited by Nev, 07 March 2017 - 01:25 PM.

[fezzasus]

Lets' remind ourselves of the original targets here.

 

It will be used for weekend blasts, occasional road trips (hoping to take it to Germany for a cousin's wedding and to Spa for the F1 GP this year) and as many track days as I can fit in.  I want the car to be as track-focussed as possible but without totally ruining it as a road car.  

 

With that in mind, is the Z20LET still the right engine?

 

The power increase will adversely impact drive-ability relative to fitting a more modern engine such as the A20NFT or the Audi option (as these engines produce more power out of the box, and have features to manage boost better such as cam phasing). I feel these have been dismissed too readily. The fact is both engine conversions have been completed before and, at least in the case of the Audi, designs are drawn and ready to duplicate.

 

Given that this work is (for the most part) being contracted out to professionals, why not get quotes for all three options from the various people that offer them before deciding? A month spent obtaining quotes and arranging passenger rides will certainly pay off rather than making a quick decision and regretting it.

 

Final point: Let's not confuse the iterative route (many small upgrades to the Z20LET) to the ideal route. Most people have ended up with improving their existing engine through a series of small changes over the duration of their vehicle ownership. Would they have made the same decisions if they knew where they wanted to end up?

Edited by fezzasus, 07 March 2017 - 01:30 PM.

[BadCop]

Hi Nev  

 

 

1. You'd need a new gearbox (with the starter on the other side).

2. You'd need different engine mounts.

3. The entire VXT loom would need to either be replaced or hacked about dramatically.

4. You'd need a new ECU specific to the engine (in order to control the cams etc etc).

5. You need a mapper who could actually map this new ECU.

6. There is little or no room for the turbo, as it's natural position is occluded by the boot bulkhead and the subframe. Heat issue next to rear subframe.

7. You'd need a bespoke and complex exhaust to try and fit in the reduced space.

8. Reroute all the hoses for the coolant.

9. New inlet air hose system to turbo, possible space constraint due to its new location.

 

 

1) Standard NA box

2) Standard NA Engine mount

3) Standard VX loom plus A20NFT engine loom (about 10 connections to make and 6 of them are the stock accelerator pedal wires)

 

4) Yep you need a modern ECU to control a modern engine (and more specific: you need an ECU that is capable of driving the A20NFT standalone)

That is what took my over a year of investigation and engineering. For that effort I don't think about 950 GBP is too much money.

Keep in mind you get a brandnew ECU including my software (unprogrammed ones will cost you over 600,- at the dealership).

I program the OEM Astra J VXR Software, Parameters and Tables and then do my magic spell to make it run standalone.

 

5) As Ross said - anybody who tunes Vauxhalls can tune the A20NFT.

I don't lock the ECU in any way. You can even do it yourself (efilive, HP Tuners, etc)

 

6) You have to clear a little space maybe a few centimeters of the boot bulkhead. Depends - I think the Turbo Clam has a bit more space anyway because they made the boot smaller.

 

7) I would always go for a nice exhaust setup - no matter if it's a Z20xyz Stage9 or a A20NFT setup. 

(And I do welding jobs too btw )

 

8) Standard NA hoses

9) Standard Turbo Intercooler with a few new samco bends (OK - I used a W2A Setup because I'm planing to go for 450 - 500 bhp with the small EFR Turbo)

 

 

 

 

 

 

In general I think you can't really compare the two setups.

 

 

With the A20NFT you use a brandnew crate engine "out of the box" for 300 to 350 bhp.

Don't open it, just bolt it in.

Due to DI and VVT you get a lot more low down "real world" torque than any Z20yxz.

 

You have to bolt a big laggy turbo on the iron lump and do massive internal upgrades to achieve similar power levels.

 

The Z20yxz was developed about 20 years ago and you can tell the difference on the first 5 meters you drive the modern DI engine.

 

If you are after maximum power dyno numbers you only have to upgrade pistons, rods, inlet cam and the big 7163 EFR Blower (direct bolt-on) to the A20NFT for about 550 - 600 bhp.

 

But the best thing is the 500 Nm it provides down low - even with the stock K04 Turbo almost from "idle speed" - no need to redline the engine all the time.

[siztenboots]

will the oil pump cope with 8000+ , just so many factors to consider for too much pain imho

[TFD]

@Nev:

 

Garrett T25G turbo

3" Exhaust

 

 

[Nev]

Nice home made log manifold.

 

It all looks quite well packaged in.

 

I can't imagine that exhaust is too quiet

 

[TFD]

Well... it might surprise you. It's just a firm sporty sound. The SC guys at Zandvoort were way louder. The small turbine housing works great as a silencer. Put a bigger turbo on and it makes way more noise.

[NOSBandit]

Any conversion is possible, just requires a bit of thought on mounting it and custom driveshafts.


I also lost a lot of weight of the rear by putting on a different exhaust.

[tibby]

Hello, that's also a solid set up you've got (engine can cope 425hp/450hp ). Very strong gearbox ( This box was also used in the ronin exige, i think, migth be wrong) Still driving @ 1 bar boost?

Did you dyno it yet?

grtz

 

Edited by tibby, 07 March 2017 - 06:49 PM.

[NOSBandit]

Hello, that's also a solid set up you've got (engine can cope 425hp/450hp ). Very strong gearbox ( This box was also used in the ronin exige, i think, migth be wrong) Still driving @ 1 bar boost? Did you dyno it yet? grtz  

I think you are right, it has been used in the exige as a upgrade. I'm only running 20psi at moment, this gives me 310hp and 320lbft of torque. Unfortunately that seems to be the most a stage 3 ct26 will produce due to restriction on the exhaust side. I have plans to upgrade the turbo next year to a gt3076r or a gt3582r. I want to be able to run 2 bar of pressure. Sent from my SM-G935F using Tapatalk

[steve-m-uk]

That looks like a 3sgte from an mr2 turbo, cracking engine. Sent from my SM-G900F using Tapatalk

[siztenboots]

looks a very tall engine?

[Rosssco]

looks a very tall engine?

 

Its about the same height as standard, but the Celica GT4 chargecooler core on top makes it look much taller.  

[siztenboots]

looks a very tall engine?

  Its about the same height as standard, but the Celica GT4 chargecooler core on top makes it look much taller.

it was more the long inlet runners on the intake but certainly not as tall as saab b234

[NOSBandit]

That looks like a 3sgte from an mr2 turbo, cracking engine. Sent from my SM-G900F using Tapatalk

It is and fully forged internals Sent from my SM-G935F using Tapatalk

[steve-m-uk]

Nice, i managed 332hp and 319lbft from my old mr2 , that was about the limit on stock turbo and block. Sent from my SM-G900F using Tapatalk

[Duncan VXR]

For me in very simple terms direct injection petrol engines are what EFI engines faced against the carburettor not so many million years ago 😉 Both could make the power but an efi engine was just better 😊 Im still not going electric mind......have to draw the line there lol DG

[Mopeytitan]

Just go all out and fit a V6, that's what I'm doing