Hey Guys,

 

Srry but i am trying to learn about boost increase and how its achieved. (learning curve) am i right in thinking you need either one to increase boost to 14 psi? But which procedure is better? with the boost controller would you be able to have low and high boost setups?

are you using stock boost gauge or do you have a aftermarket one plumbed in, but 7psi would be safety boost, no doubt due to code 34 det sensor fault as the wire gets a lot of heat at the back of the engine and tents to go brittle inside hence throwing the code 34 error, its also one of the most PITA locations to work on if the car is in the zed, you would either have to strip the plenum, and lower plenum off the car to access it, if you dont have the engine out, or if the engine is out, renew the sensor and cable while you are there.

 

One thing i would say before upping the boost on any VG30DETT, would be get it checked over first make sure its a healthy engine as you put more stress on the components running at higher boost levels.

 

Fitted an aftermarket gauge over the weekend, stock said I was running equivalent to about 13.5 psi so I didn't believe that and my new one went to 7 and sometimes 8.

 

Have a smoking issue that I need to deal with before I would even think about putting anymore power through my zed. Changing the PCV valves sometime soon if no joy there will have to get the turbos and seals checked so would need the engine out anyway and would change the DET sensor while I'm in there.

 

Will running safety boost be a problem in the long run or is it ok while I start eliminating other problems first?

 

Ive ran boost jets and also ran a EBC on 2 different zeds, wouldn't worry about running lower boost due to rain, you just don't push the accelerator pedal harder, this controls boost well i found with boost jets and EBC, not really sure you would want to "give it the beans" in the wet unless you have a set of steel balls anyway, regardless of what you are running lol

 

I agree, this is why I asked Paul to justify his statement. IMO, you set your car up with the amount of power you want, then control it with your foot. Fair enough on modern cars when changing to 'sport mode' or 'race mode', as it tends to also change traction control and suspension settings etc. As vods says its a lot of money just so you can say... 'well honey, as it's raining today, I'm going to electronically lower my twin turbo boost pressure to 8psi. That way, when I'm on my way home from work, redlining every gear full throttle, I won't crash'!

 

Are there any ways of controlling boost spikes? What does an ebc do that the oem waste gates doesn't? All I can think of is that the restriction of the jet causes a lag in the waste gate movement, so maybe putting the jets closer to the waste gate rather than the normal easy option?

optimal boost would come down to what turbos you are running, what injectors you have and what map you are running, but if you have stock injectors, a chipped ecu, decats, airfilter and stock turbos, you would be wanting 14psi and below

 

Stock boost is 9psi

safetyt boost is 7psi

 

In that case, should I be slightly concerned that the Boost gauge in my car appears to always be in Negative numbers?!?!

 

Do boost jets work on the basis that when you want increased boost, you push a button and it runs for a certain amount of time? Or do they just run all the time?

 

Thanks

In that case, should I be slightly concerned that the Boost gauge in my car appears to always be in Negative numbers?!?!

 

Do boost jets work on the basis that when you want increased boost, you push a button and it runs for a certain amount of time? Or do they just run all the time?

 

Thanks

 

:helpsmilie::no:

 

just all the time

ok cheers.

 

Should I be worried that my boost guage is running in negative numbers? Does that mean its not wired up properly?

 

I'm also guessing its best to stay away from the manual boost guages that you can get off ebay for about 20 quid?

Negative numbers are normal as it is showing that you have vacuum

when key in and electrics on, sits at 0, when car started sits at -14 or what ever negative numbers your gauge does, when boosting it goes from neg to positive indicating boost.

 

as for a £20 boost gauge, cant see why it wouldn't work, its only reading vacuum pressure.

nothing wrong with a nice autoguage ;)

Yeah I'm pretty sure it goes from -14 to +14 on the boost gauge

 

Here's the cheapo boost gauges I was on about that I'd seen on ebay. Expert opinions please?

 

http://www.ebay.co.uk/itm/Manual-Boost-Controller-MBC-Kit-PSI-Boost-Gauge-For-Any-Petrol-Turbo-Car-/370641437243?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item564bf3823b

http://www.ebay.co.uk/itm/UNIVERSAL-MANUAL-BOOST-CONTROLLER-VALVE-KIT-ANY-PETROL-TURBO-CAR-/261005822892?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item3cc528cbac

 

Cheers

Edited August 29, 201213 yr by agl89
Edited links

I've got a boost controller Greedy profec b spec thing, and it has two settings, low and high, high been at 14.5 psi and low been at around 9. and to be honest, i never change it, as its already been stated, just control the boost with your foot, the less heavy the less boost. I can't remember the last time it was in low boost. But i'm sure there must be other benefits of an EBC. what about been able to set up the gain etc, am i right in thinking that effects the lag?

How much are a set of boost jets normally? Obviously if they run all the time then I'll just need to make sure that I'd be lighter with my right foot... unless those Manual boost controllers look like they might be any good?

How much are a set of boost jets normally? Obviously if they run all the time then I'll just need to make sure that I'd be lighter with my right foot... unless those Manual boost controllers look like they might be any good?

 

they are normal welding tips, most go for the 0.8mm ones, that give around 14psi and you can pick them up from B&Q for a couple of quid, not bad for something so simple, plus its a always on power gain, just remember though, before upping the boost, sort out things like air filter, exhaust, its needs to breath properly, also a chipped ecu like a zedworld one to cope with the higher boost level correctly or you could end up killing your engine through wrong fueling map.

Yeah, cars already got uprated air filter, dump valves and a japspeed exhaust. Dont think its been de-catted though, and definitely hasnt had the ECU done.

 

My previous car failed its MOT as it was decatted - so was reluctant to originally do this on my zed - is it the same with a zed or would it pass MOT as its over a certain age?

 

I am tempted by one of those manual boost controllers for about 20 quid but I reckon theyd be a bit shit lol

Yeah, cars already got uprated air filter, dump valves and a japspeed exhaust. Dont think its been de-catted though, and definitely hasnt had the ECU done.

 

My previous car failed its MOT as it was decatted - so was reluctant to originally do this on my zed - is it the same with a zed or would it pass MOT as its over a certain age?

 

I am tempted by one of those manual boost controllers for about 20 quid but I reckon theyd be a bit shit lol

 

300zx's up to i think its year 1995 can still pass a MOT on a non cat test, even though the law states after to 1992, cars need cats, as they are not on the MOT data base, also make sure they put your car through as a 300zx and not a 350z as it will never pass even with CATs on it (had that before and so have others) i was lucky though as i spotted the error before he did the print out.

ah cool, I'll bear this in mind. Will have a chat to Jeff about it when I'm off to Zedworld in a couple of weeks. Cheers :)