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vincyboy
09-03-2010, 08:42 PM
what is the most boost i can run on my stock 1998 galant vr4 (manual)?

AlanDITD
09-03-2010, 08:46 PM
will vary from car to car, you can up the boost till you hit fuel cut and then take it back a touch, best to have it set on a dyno though just to be sure your afr's are ok...

dont think anyone has had any probs just turning it up though, the MAF sensor should compensate with more fuel, but condition of other parts i.e fuel pump may play a factor!

Turbo_Steve
09-03-2010, 09:49 PM
80psi. Just fit a restrictor in the inlet tract :D

Most people find they can run around 1Bar on standard cars, though this will generally drop as you fit freer flowing exhaust, more efficient intercooler etc.

AlanDITD
09-03-2010, 11:09 PM
80psi. Just fit a restrictor in the inlet tract :D

Most people find they can run around 1Bar on standard cars, though this will generally drop as you fit freer flowing exhaust, more efficient intercooler etc.

steve i think your being a touch optimistic, the inlet tracct mod wil allow 76psi and 93hp. Its true as i read it on the internet

Turbo_Steve
09-03-2010, 11:29 PM
Only if you fit a resisitor in the cam-sensor feed.

Subaru ETA
10-03-2010, 12:18 AM
just crank it up until it breaks a conrod or smashes the pistons then back it off a couple...... if im not mistaken this has been covered a couple of times before...

AlanDITD
10-03-2010, 12:20 AM
Only if you fit a resisitor in the cam-sensor feed.

what about putting a chicken dipper in the VTEC solenoid? i heard that helps

Turbo_Steve
10-03-2010, 09:00 AM
VTEC just Kicked in YO!! [/westwood]

peter thomson
10-03-2010, 09:28 AM
Thought I logged into scoobynet, way to put people off guys

elnevio
10-03-2010, 09:45 AM
LOL! The question was actually answered in the first two posts though! I.e. about 1 bar or until you hit fuel cut! :)

AlanDITD
10-03-2010, 09:46 AM
well i did put an honest and helpful answer at the beginging....sorry peter, sorry OP :)

Kieran
10-03-2010, 09:50 AM
Peter got there before me! :flamed:

/pan

Thinking further around the issue, it's probably time we had a set of 'Top 10' FAQs so that we can just link-drop for questions like this. I remember working on them with Nick and Andy some years back, but I can't remember where they went.:thinking:

Turbo_Steve
10-03-2010, 12:39 PM
Sorry, it's just one of those questions that indicates a total lack of knowledge regarding engines, ECUs, tuning and the car in question, specifically what's going to make it go bang.

If you're asking "what's max boost" as a one line question, the general answer is "You don't know enough to be fiddling with it".

It's just one of my pet hates. Sorry VincyBoy: Kieran and Peter are right, it wasn't a very helpful response on my part. But it's fair to say that if you have to ask, you need to know a lot more.

Look at it this way: you wouldn't pop online and ask "How many floors can I add to my house?" as there isn't a simple answer.

It's the same with max boost. The car doesn't measure boost. At all. Anywhere. It measures airflow which it converts into load.
Depending on the car, this can result in a peak allowable boost of anywhere between 0.7 and 1.0Bar, however it varies and, perhaps more importantly, depends how quickly your car builds boost, and how fast it revs.

Furthermore, you need to have a checklist of things done before you increase the boost:
Generally new plugs and leads are good idea, as many people find they become a problem when you start increasing the boost, misfiring and making the car feel very poorly.
Are you using a decent high temperature oil?
Are you running 99+Octane fuel?

vincyboy
10-03-2010, 04:31 PM
I'm using Lucas 20W- 50 synthetic oil and the fuel....lol well where i live (in the Caribbean) we get very poor quality fuel. 85 octane to be exact. but i use an octane booster when i want to up the boost a bit. the reason i was asking about how much boost i could put it up to was cause i assumed you guys would have known what type turbo i have and the cfm of it and whats not hence the reason i said "stock vr4". But im learning still anyways. thanks for the help. oh and i dunno if you can help wth this but anytime i accelerate past about 3000 rpm i hear a high pitched beeping sort of sound.

WizardKing
10-03-2010, 04:41 PM
Hard to say with an online description but check all belts, immediately.
Could be a turbo falling apart.

Can you take a short video of it ?

Wodjno
10-03-2010, 04:56 PM
You sure you haven't got a boost controller fitted with a peak boost limit alarm ?

vincyboy
10-03-2010, 05:16 PM
no its just a turbo xs manual boost controller.....and i dont think it can really be anything with the engine cause it seems to be ceoming from the back. I was wondering if it may be a problem with the ayc pump or something but yet it does sound like an alarm!

elnevio
10-03-2010, 07:22 PM
Very very strange on the noise front? Perhaps a video clip would help.


Anyway, I think the octane rating used in many Caribbean countries is MON and not RON. So 85 MON is about 95 RON. Hopefully, the octane booster is increasing the RON value to closer to 100.

Turbo_Steve
10-03-2010, 07:32 PM
I'm using Lucas 20W- 50 synthetic oil and the fuel....lol well where i live (in the Caribbean) we get very poor quality fuel. 85 octane to be exact. but i use an octane booster when i want to up the boost a bit. the reason i was asking about how much boost i could put it up to was cause i assumed you guys would have known what type turbo i have and the cfm of it and whats not hence the reason i said "stock vr4". But im learning still anyways. thanks for the help.
Now that's a much better question. You'd probably do best to have a read of this one:
http://www.clubvr4.com/forum/showthread.php?t=39635&page=2&highlight=flow+rate

What you're looking to achieve is discussed pretty thoroughly there.
If you're running 85MON fuel, or 95RON, I would STRONGLY reccomend looking at enrichening your fuelling, or remapping the ECU before you try and increase the boost. At the very least I would want some Knock monitoring.

Octane boosting additives are no substitute for high quality fuel, unfortunately.



oh and i dunno if you can help wth this but anytime i accelerate past about 3000 rpm i hear a high pitched beeping sort of sound.

I would guess you have a boost leak. It's either your dumpvalve partially opening, or a vaccum hose with a hole, or possibly someone has removed a boost gauge from inside the cabin and failed to block the hose properly.

666damned
18-03-2010, 11:01 PM
[QUOTE, or possibly someone has removed a boost gauge from inside the cabin and failed to block the hose properly.[/QUOTE]


pmsl..................

Nutter_John
18-03-2010, 11:04 PM
pmsl..................

You may Laugh but I have seen it a few times !!!

micha11
19-07-2010, 08:25 PM
my engine runs with 1,3 bar. there is a big intercooler, walbro, 102 octane map, downpipe and exhaust 76 mm, piping, 8 plugs new ignition leads and ground cables, hks evcs boost controller.
i use 10w40 motul chrono 300v engine oil(ester), but now i need a oilcooler because is beeing to hot. last turn on highway , sprint wihz new bmw m3 , exhaust temperatur in downpipe 950°C and also water to hot.
good thanks for free highways in germany. it has been 270 km/h. . .

Wodjno
19-07-2010, 08:30 PM
good thanks for free highways in germany. it has been 270 km/h. . .

Almost exactly what i had from my 1st VR4 /yes

WizardKing
19-07-2010, 09:58 PM
Ahh, but did you find enough orifices to use "8 plugs" though ??

lol

Wodjno
20-07-2010, 12:23 AM
Ahh, but did you find enough orifices to use "8 plugs" though ??

lol

Yes.. /yes 3 at the rear and 7's at the front :D

WizardKing
20-07-2010, 01:38 AM
I'm getting mathemixometosis !!!!

micha11
21-07-2010, 04:20 PM
i have 8 plugs front and rear, front 7 there has been problems by boost over 1,0 bar