G8T-760 - Crank the boost? - Retro-Renault

**MicKPM** · 2nd February 2007, 02:33 PM

Does anyone know if:

A - It is possible to do and
B - What a safe level is?

I thought the G8T's had to have the boost levels set by an X25? Can it be DIY'd?

**Chet T16** · 2nd February 2007, 02:38 PM

The 2.2 is it?

**MicKPM** · 2nd February 2007, 02:40 PM

Yup - 2.2 Tubby Oil Burner. I'm sure i've read somewhere that it needs to be set electronically.

**Chet T16** · 2nd February 2007, 02:42 PM

Yup, if you wind it up manually it'll just go into limp mode

They can be remapped

bbracer16valver · 2nd February 2007, 02:52 PM

is it the 12v 2.2 lag engine??

as my dad has been wanting sumat done for a while, everyone says you cant chip that lump

**MicKPM** · 2nd February 2007, 03:15 PM

Yeah its our old one and it's also the 12v. The lad has called up asking what he needs to do and I told him to back up before trying to play with anything. Derv Dr wants the best part of £300 to remap and increase the boost level. I know it can be done but I didn't think it was a simple case like it is on the Escort TD's

bbracer16valver · 2nd February 2007, 05:38 PM

as far as superchips were concernd fook all could be done

update when/if it gets done

**he's intrested as it seems to be limited to 115mph

**

**MicKPM** · 2nd February 2007, 11:09 PM

Funny place SuperChips (Are chips really "super"? I dunno, we'll save that question for another day) They don't actually do anything other than sell you chips with pre-installed maps on them. If they can't supply you something, in there mind, it can't be done Ash

Derv Dr in Derbyshire said it can but he wants close on £300 for the remap and boost tweak. It's not my car anymore though so if he does it i'll not know. I've just told him not to be a gimp and try to manually adjust the boost cos if he does he should n't bring it to me to be looked at.

stan · 2nd February 2007, 11:27 PM

im not familiar with this engine or the control system it runs, but most modern diesels can be tweaked quite well be "fooling" the ecu....the same way people try to do on petrol engines, but with poorer results mainly due to a petrol engines sensitivity to AFR.

An example...at my old work we had a Jeep Cherokee CRD (if thats what it is??)...big diesel thing. Anyway, the bloke/cutomer had this diesel t"tuning box" so i fitted it for him. Basically, all it done was interfered with the pressure sensor on the fuel rail, so as to alter resistence "telling" the ecu that fuel pressure was low. The ecu then ups the fuel pressure...bingo bango more torque. The instructions literally said "keep increasing setting until either black smoke is clearly visable, or limp mode kicks in"...quite funny really!

Same principal can be applied to boost control.

Huw · 2nd February 2007, 11:51 PM

Hmm, I thought this would be like its 1.9td sibling of the same era? Both being mechanical diesel injection. Mind you the 1.9 doesn't even have an ECU, wasn't aware the 2.2 did either.

stan · 2nd February 2007, 11:55 PM

if its mechanical diesel, crank the pump pressure up and fit a bleed valve...jobs a gud un!

JB · 3rd February 2007, 08:51 AM

i'll have to do that to my old pug when i decide to get rid...see how much she can take!

tom 16v · 3rd February 2007, 09:46 AM

i have a diesel tuner box fitted on my focus 1800 tdci (i call it a super chip but its not lol its a £120 black box with wires lol) i paid £50 for it then fitted it and never noticed shit so took the focus to power engineering for them to look they adjusted the tuner box quite a bit and then put it on the rolling road and recorded 146 bhp and 312 nm of torque so considering standard the focus was running 115 bhp(ford say 115 but usually slightly more after a few k on the clock) and 284 nm of torque so the little diesel yuner box does work well and the guy at pe is 100% they are 100% safe to use and do not cause any damage whatsoever and mine smokes less is faster and more economical to run now,
it just plugs on to the sensor on the common rail

stan · 3rd February 2007, 12:22 PM

yes...sounds like it works on the same principal as ive described above.

**MicKPM** · 3rd February 2007, 04:56 PM

It's got a Sagem ECU but I think that's just for the heating of the plugs at various stages. So you think it can be done then with it being mechanical?

Huw · 3rd February 2007, 06:04 PM

Quote:

Originally Posted by MicKPM

It's got a Sagem ECU but I think that's just for the heating of the plugs at various stages. So you think it can be done then with it being mechanical?

Sounds like your desbribing the glow plug relay. The injection timing etc is controlled by the mechanical injection pump.

3rd February 2007, 08:51 AM	#12 (permalink)
JB Membre Join Date: Oct 2006 Location: Swansea, Sunny South Wales Posts: 456	i'll have to do that to my old pug when i decide to get rid...see how much she can take! __________________ JB