87uk944t

I have just fitted an aftermarket boost gauge and a vdo fuel rail gauge and i got the following readings
1st gear- 12 psi
2nd gear-14 psi
3rd gear- 16 psi
4th gear- 19 psi
5th gear- 21 psi
fuel rail gauge- 32 psi at idle
can anyone tell me if these readings are normal as i have nothing to compare them too
TIA Graeme

ian

you are getting 21psi off your turbo? and its stock? and you have not blown a Head Gasket yet?

That is a lot of PSI to be blowing into a stock motor with guessing from your sig has stock injectors, and is using the stock k26/6. You are going down a path of the blown headgasket if you continue to his 21 psi....

sybelix

well, those 19-21 psi seems quite high, if you haven't changed your injectors..
It may be runnin a bit lean on high rpm

Mike S

That's a pretty large spread. Not sure why that spread is so large. On my stock turbo 87 I'm getting 15psi in 1-3rd and 16-17psi in 4th and 5th. Maybe you have a boost leak somewhere and the extra time spent boosting is allowing the turbo to catch up and create more pressure?

87uk944t

yep am running the stock injectors and turbo, i dont know why my boost is running so high as my boost enhancer is still set at factory settings, which is 10 psi, which i am led to believe is actually about 15 psi on an aftermarket gauge, i was actually expecting the boost pressure to tail off thru 4th and 5th after reaching its peak in 3rd gear

87uk944t

mike s, i have no idea either but i shouldnt really have any vac leaks( i hope) as i pulled all the original vac lines and replaced them with a new vac line kit from lindsey racing at the same time as fitting my gauges, my car doesnt feel that quick thru 1st and 2nd, but 3rd thru 5th is unbelievably quick, like you say i was expecting a far more even spread thru the gears of boost pressure

Mike S

One quick note.....i'm not suggesting a vacuum leak as much as I'm suggesting that you might have a leak between the turbo down pipe and the wastegate. Check the wastegate pipe ring(mine was cracked when i bought the car) and also check along the pipe to the wastegate for any leaks. You'd probably hear it though. Is your turbo making a loud whistling when it spools up?

adrial

I agree, thats a huge spread. I see 14-15psi in 1st and 16psi in 5th.

Does anybody else have an LBE and a boost gauge? Maybe its the behavior of the LBE and not the car?

87uk944t

mike, recently had wastegate off to shim it and replaced the short sections of exhaust pipe coming from it, also replaced the rest of the exhaust only a few months ago with a 3" stainless system so am kinda hoping i aint got any problems here either

Mike S

I've got the reliaboost on mine. It's basically the same thing though. A little check ball in there. I can't see why it would get stuck in the higher gears only....unless i'm missing something.

87uk944t

nope turbo doesnt make any whistling noise when spooling up as far as i am aware, boost gauge also sits at 20inhsg of vacuum when not on boost is that normal or does that also seem like a lot??

Sami951

I don't mean to hijack this thread, but what would cause a whistling spool up sound? Mine goes like whuiiiiiisssshhh when you press the loud pedal, and it's not quiet by any means...

It seems to build pressure too slow as well, I'm not getting full boost until at around 3500-4000rpm in third gear. Stock K26/6...

Danno

How old is your LBE? These use rubber and plastic innards that gets clogged up over time. The spread between max-boost levels in each gear is kinda large. I'd adjust it for 15psi max-boost in 5th gear to be safe.

"Mine goes like whuiiiiiisssshhh when you press the loud pedal, and it's not quiet by any means... "

Check for intake-leaks. There's a hose underneath the airbox that should be plugged up. I used to be hooked up to the belt-covers with a short hose. Also check your intercooler pipe hoses as they like to split parallel to the hose-clamps. Also tha tlarge hose coming out of the turbo can develop a split on the back side that only opens up under boost.

Sami951

Danno, thanks for the suggestions, I guess I now have something to do for tomorrow

btw how are the map kits coming along? Not that we're impatient over here or anything ...

sybelix