Too much boost?
Turbo Mini Forums

Hi Guys,

Finally finished my engine install and have the turbo set on factory pre load on the actuator (its a GT1549)

I took the car for a run tonight with my new AEM gauge installed what displays AFR & Boost, I took a data log I am getting readings of between 11-13psi. I only wanted to run a max of 10psi

should I try to adjust the actuator to reduce boost?

any ideas?

you can try winding actuator pe-load off a turn at a time but be carefull to keep some preload or turbo spool up time will suffer
if that doesnt lower the boost enough you will need another actuator

Yes i moved to the darkside

Instagram @jdm_brett

Cheers for that Brett I thought the actuator was how best to lower boost

But I wanted to ask one of you lot in case there was another option I didn't know

Too much boost ?

Not something we hear on this forum very often !!

Just leave it. 11-13psi is good.

If something is worth doing, it's worth doing half of.

yeah I know I thought I would get comments like this :)

but as I have a basic set up with standard gearbox/dif and pistons

I have been told anything above 10psi would not be advisable

gearbox should be fine some peeps running silly numbers on stanard box diff may be your problem if your getting good bhp, pistons should be ok if your timing and fueling are ok

Done now needs redoing lol

Just don't go daft booting it everywhere.

If something is worth doing, it's worth doing half of.

whats the spec?

the deciding factor will be if its been put together peoperly/is it a second hand tired unit?

but more importantly, a proper set up...

Is there an intercooler? You will definitely want one

Drives
-Ford S-max Mk2 Ecoboost
-Rover 100 VVC #2 - track project

Searching is all you need on TurboMinis

if it has standard helical drops and gearset/ diff ......... i can assure you that if you dont turn the boost down to 10 psi or under it will all end in tears for you.

Hi guys,

I managed to get the psi down to 8 winding the actuator in so I'm pleased about that

The spec is:
Ap clutch and grey plate
Standard 1275 head re worked by turbophil
Spi pistons, crank & cam
1.5 highlight rolling rockers
Mega jolt ignition
Intercooler from escort rs turbo

Car runs great in my opinion just need to get it on rolling road

This is a clip from last night after I turned the boost down

http://youtu.be/n35dWLdK0pw

Howley cow spi pistons!! Keep the boost down or it will end in tears

Yes i moved to the darkside

Instagram @jdm_brett

Brett

You think 10psi is too much for them?
I know they have big oil ways is that why you think they can't take boost?

I've seen an SPI piston before they don't look particularly robust.

Start saving now for a new set & a rebore! lol

If something is worth doing, it's worth doing half of.

I have never tryed but i do have a cut up spi piston.. the oil slots must be an inch or so

Yes i moved to the darkside

Instagram @jdm_brett

I ran 10 psi through my old engine, using non mg metro na pistons. They held up fine. The main thing is to have it set up properly. Though yours could be ok for a budget low boost motor. Whats the compression ratio? Its not ideal though and there is always a slight element of doubt in your mind. If i were you i would get what you have set up properly and build a nicely specced bottom end up as well ready to drop in.

Yeah the plan is to run this but start another engine build as I am already addicted!!

The current setup is running 9-1 CR I am not going to go over 10psi and I don't wheel spin it everywhere plus at moment I've got it set around 8psi

Got rolling road booked for 2 weeks time

The earlier comment about not booting it everywhere is relevant.

I reckon that with an intercooler and sane ignition map as well as an intelligent right foot (!) you will be fine, even with the original 13 psi.

I used standard MG Midget pistons and a standard 12G940 head (9.0 :1 CR) and 20 psi when I was a bit green about the whole turbo thing and they survived.

I did realise that if I held it on 20 psi and WOT for very long I was likely to be walking home.

Tadge44,

Yeah I am pleased with the way it's running and I am sure when on the rollers it will improve

I am not a Chav when it comes to driving it I give it a little boot hear and there but I do know at the end of the day I've not built a bullet proof engine just a nippy little weekend car

It's my 1st build so I'm like many a little green also

Every time I see this title I have to smile.

Own the day

my two cents worth is that its more about the driver than the strength of the components meaning i had my 1098cc na motor making 68 odd hp destroy a fresh std box and diff broke the double roller bearing cages the bits of metal when threw the bearings destroying the cam oil pump crank bearings any thing with an oil feed really as well as chew up the gear set and destroy the inner and outer cv joints
what i am saying is drive like a dick and you will fuck your car i lent the hard way take it easy you can still go fast with out breaking things.. ease the gas on and of not like a light switch! 5k rpm standing starts are fun but bad!
i cant see why a good std set up and maintenance scheduled cant handle HP if its not abused but i must say there is a line when you make to much power and it just gives up like so many other have found