mk4 na-t tuning

Mk4 supra NA-T - Ive used the search bar and got some answers but want to comfirm if this is correct.

it seems like its possible then to keep the standard NA pistons on and use the thicker tt head gasket to reduce the compression.. Upgrade the fueling/fuel pump, front mount intercooler, new fully programmable ecu and seems like you can run boost upto 2.0 to produce over 500brake i think.. with upgraded clutch and r154 box

p.s im looking to probally run no more than 550 brake

and would not run 2bar of boost

You'd be able to run about 1.8bar with the headgasket change but that's the absolute max, I'd say 1.7 to be safe. It's been done in the past and seems as though it's worked quite well. It will be better to use pistons instead to drop compression though as it retains the squish area which means it works more efficiently basically. There's other things to consider as well such as oil temp/pressure, air/fuel ratio and maybe fuel pressure gauges. You're taking the engine way past the spec it was originally designed for so you can't be too careful with monitoring things.

My ignition system worked fine when I was NA and then had to replace nearly all of it after going NA-T. So think about that too maybe. You'll definitely need colder grade spark plugs.

T.T. pistons with T.T. head-gasket = static compression 8.1:1 ~ Capacity for more boost than bottom end can take and give a laggy launch ~ Squish 3.25mm

T.T. pistons with N/A head-gasket = static compression 9.0:1 ~ Good for 2 Bar (99 RON) ~ Squish 1.14mm (750? bhp)

N/A pistons with T.T. head-gasket = static compression 9.2:1 ~ Good for 1.8 Bar (99 RON) ~ Squish 2.15mm (700? bhp)

N/A pistons with N/A head-gasket = static compression 10:1 ~ Good for 1 Bar (99 RON) ~ Squish 1.14mm (500? bhp)

Take a look at the N/A-T group, you'll find answers to most of your questions there.

http://www.mkivsupra.net/vbb/group.php?groupid=49

thanks mate, its whether i decide to buy the na-t and then have a few thousand to spend on gettin the r154, any other mods needed to make it all work. or do i use my loan and save up 15k for a 6speed twin turbo.

if i buy an auto na-t for 5k, 3.5k for a r154 and fitting. then that leaves around 4.5k for me to spend at the mo on the car. what do you think

thanks mate, its whether i decide to buy the na-t and then have a few thousand to spend on gettin the r154, any other mods needed to make it all work. or do i use my loan and save up 15k for a 6speed twin turbo.

 

if i buy an auto na-t for 5k, 3.5k for a r154 and fitting. then that leaves around 4.5k for me to spend at the mo on the car. what do you think

If you have that much to put into a NA-T then just save a bit more and get the TT6, will be better in the long run.

If the 4.5k is spent in the right places then you could have yourself a very nice car.

id love to buy the 6speed twin turbo but it would literally leave no spare cash at all if i spent 15k

id love to buy the 6speed twin turbo but it would literally leave no spare cash at all if i spent 15k

If you are buying an NA-T for 5k, then be sure it's been done with quality parts and a proper map etc. Some NA 5 speeds are selling for that price, so I'm wondering why the NA-T is so cheap, even if it an auto.

A lot of NA-T's are done on a budget, and it shows when they go wrong or just lack anything lackluster when you put your foot down.

Worst thing you could do is buy a lemon and you will quickly piss away the extra money you had fixing the thing cause it was done cheaply at first. If you are set on an NA-T i'd up the budget for a car to 7-8k and find yourself a really nice example that needs no messing around with.

i wouldnt say im set on buying a na-t.. id much rather get the 6 speed tt but it just comes down to money. I have doubts wen i think about na-t's because i think what if i want to go more power down the line, like 550 then will i need to get tt pistons in, which, if i do thats big money straight away.. i think it just interested me getting a supra cheap an having ££££'s left over to spend so i can make a custom build for me.. i dont know.... thats why i thought id ask for your help if you was in my shoes

If i buy a tt all it means is that whatever mods someone has done already will have to stay for abit until i can certain things in the future

thanks mate, its whether i decide to buy the na-t and then have a few thousand to spend on gettin the r154, any other mods needed to make it all work. or do i use my loan and save up 15k for a 6speed twin turbo.

 

if i buy an auto na-t for 5k, 3.5k for a r154 and fitting. then that leaves around 4.5k for me to spend at the mo on the car. what do you think

With a Hybrid transmission you'd be more than £3k better off, or with flappy-paddles for £2.5k better off.

http://www.mkivsupra.net/vbb/group.php?groupid=57