Newbie with a few questions

[Mash]

hello all im a newbie here so thought id get the first post out of the way ,

recently i have purchased a 1991 3.0 turbo but since ive never owned one before im hoping you can help me with a few questions ,

firstly is my oil pressure ok ?

on idle i get 20psi according to the gauge on the dash
on basic driving i get 35-40 psi and if im going for it i get around 50 psi , however my concern is that the gauge goes up to 120psi

the car has 103k miles on it however it came with full toyota service history and also a reciept from toyota saying that it had a complete new cylinder head put on the car at 92k im presuming the previous owner blew the cylinder head gasket and maybe cracked or warped the cylinder head resulting in it needing a new one , i trust the work of toyota but as i say im a little worried about the oil pressure ,

if all is well i am planning on moderately modifying the car , firstly i would like to start by upping the boost, my last turbo vehicle (tommy kaira m20b) was running around 18psi of boost however according to my gauge the supra is only runnig 6 psi , what is a safe amount to set the boost to on a stock car ,

i look forward to any replys and imagine ill have many more questions in the not too distant future

cheers for reading

mash

[lplpaca]

Welcome to the board, sorry can't really answer your uestions on Turbo boost, I'm an N/A owner, but if you search the threads you will find plenty on info on it - it is a popular topic.

Oil pressure seems about right, maybe a little low on idle but ok for other driving, I get similar on my N/A, tho slightly higher, maybe 25 to 30 on idle, they do seem in general to run a little lower at higher mileage, but I'm sure someone else will confirm your oil pressures and turbo boosts, IIRC they don't take the boost up too much on stock cars. Once again you find plenty of info on here if you search the threads,

Hope you have fun, and a BIG smile factor in your new acquisition :)

Paul C

[damo_mk3]

hello all im a newbie here so thought id get the first post out of the way ,

recently i have purchased a 1991 3.0 turbo but since ive never owned one before im hoping you can help me with a few questions ,

firstly is my oil pressure ok ?

on idle i get 20psi according to the gauge on the dash
on basic driving i get 35-40 psi and if im going for it i get around 50 psi , however my concern is that the gauge goes up to 120psi

ok the oil is fine as mine is the same as yours, the hg are know to be a problem and u need to get a mhg (metal head gasket) really

moding and psi/bar to run info

STAGE I

We know we need to increase air flow, so lets start there. First lets make sure the air coming into the engine is clean and without restrictions. This requires us to have a nice air intake system. The K&N FIPK solves this portion of the equation rather well, with it's 1,000,000 mile guaranteed and washable filter system. The HP gain with this is modest (5-7hp), but it gets us the clean air in the quantity that we want for a turbo car that is planning on running 11.5 psi.

STAGE II 250HP

Secondly we want to make sure that we can get all of that air out of the engine as efficiently as possible. Since we have a large air pump of an engine we want to be absolutely positive that we can get the exhaust energy OUT of the car as fast as it goes in! On a turbo car, BIGGER IS BETTER, because restrictions create back pressure and back pressure hinders boost!! Remember, it is BOOST that gives us POWER! A good quality exhaust system is the KEY here in minimizing restrictions. Included in this kit is the K&N FIPK from Stage I above and the HKS ($499.95) Cat-Back Performance Exhaust.

Stage III - 285 HP

Now that we have an intake and exhaust system, we can increase the boost up to 11.5 psi and gain some HP. An electronic boost controller is the key to this portion of the equation. An electronic boost control regulates the factory turbo boost and is fully programmable from lower to higher settings. All of our boost controllers will do a good job for you, so select the one you feel most comfortable with. We provide the GReddy Profec B fully electronic boost controller is supplied with the Stage III Kit. Fully adjustable boost provides a great solution to boost control on your Stage III Supra Turbo. This kit includes the parts from Stages I & 2 and adds the GReddy Profec B electronic boost controller.

Stage IV 300HP

We pick up on the exhaust system where we left off previously to further reduce exhaust back pressure and to help that turbo spool up (reaching maximum rpm quicker). We do this by eliminating both catalytic converters from the exhaust system. Yes, this officially makes the car an off-road vehicle, but it is good for the final 20HP in the equation, so the choice is yours. You will receive all of the components listed in Stages 1,2&3 plus we provide an HKS downpipe and the SupraStore.com test-pipe.

Stage III and above packages are highly recommended for cars with HKS metal head gasket modifications for absolute durability and robustness.

above taken from suprastore.com

damo

[Trevor]

On idle i get 20psi according to the gauge on the dash
on basic driving i get 35-40 psi and if im going for it i get around 50 psi , however my concern is that the gauge goes up to 120psi

Welcome to the group.

If anything, your oil pressure is a little higher than the Turbo average, but it does depend on the viscocity of the oil you are using and the sensor isn't particularly accurate.

The reason the gauge goes up to 120 is that it is the same guage as used in the NA, where the peak oil pressure is 80+ psi. NA oil pressure across the range is roughly double that of the Turbo.

[Bryank]

Hiya & Welcome! :action-sm

The reason the gauge goes up to 120 is that it is the same guage as used in the NA, where the peak oil pressure is 80+ psi. NA oil pressure across the range is roughly double that of the Turbo.
Interesting.. The Turbo runs lower oil pressure? -- guessing due to the extra takeoff for the turbo & the oil jets as the systems are identical apart from that?

[Trevor]

Interesting.. The Turbo runs lower oil pressure? -- guessing due to the extra takeoff for the turbo & the oil jets as the systems are identical apart from that?

I guess so. This also means that the flexible pipes to the oil cooler don't seem to leak on the Turbo, whereas in my experience, they always seem to ooze oil on the NAs.

[MKS]

"We pick up on the exhaust system where we left off previously to further reduce exhaust back pressure and to help that turbo spool up (reaching maximum rpm quicker). We do this by eliminating both catalytic converters from the exhaust system. Yes, this officially makes the car an off-road vehicle, but it is good for the final 20HP in the equation, so the choice is yours. You will receive all of the components listed in Stages 1,2&3 plus we provide an HKS downpipe and the SupraStore.com test-pipe."


U can get rid of both cats as the age of the car it does not require cats at all.. mine has passed 2 MOTs without cats and the emissions have been somthing like 0.2% :)

The turbo on our cars r only really good for 14psi... i guess they used a turbo liek this as there was not much need for huge psi as the engine did a lot of the work..

if u want to go higher with te boost then best to get a hybris turbo.. but u will also need a Lexus AFM and some bigger injectors to run properally..

[BONDY]

We do this by eliminating both catalytic converters from the exhaust system. Yes, this officially makes the car an off-road vehicle, but it is good for the final 20HP in the equation, so the choice is yours.

damo

As far as i am aware only after 1991??? or only in the states :bigeyes: :duck:

[Finfon]

hello mate and welcome :action-sm some one close to me at last :)

[supratoy]

hello all im a newbie here so thought id get the first post out of the way ,

recently i have purchased a 1991 3.0 turbo but since ive never owned one before im hoping you can help me with a few questions ,

firstly is my oil pressure ok ?

on idle i get 20psi according to the gauge on the dash
on basic driving i get 35-40 psi and if im going for it i get around 50 psi , however my concern is that the gauge goes up to 120psi

to on a stock car ,

i look forward to any replys and imagine ill have many more questions in the not too distant future

cheers for reading

mash
Hmm,
Now thats interesting cos mine has the same oilpressure readings and according to the book it is 36psi to 71psi at 3000rpm,
however if i rev the car i can hear what me and Darkett and Supra89 think is a slight big end rattle for a second at about 2500rpm then it disappears, car runs fine with no problems and the modded head has certainly helped with the power, but i am worried enough that i am gonna attempt to drop the sump and pull the main bearings and bigend bearings to see how worn thay are cos we all know that the mains carry the oil pressure, so if i,m gonna be modding it after my 500mile break in period i dont want the engine to blow its crank,has anyone droped the sump with the engine in situ? Darkett seems to think its possible but i would like to know if anyone has actually done it and can you get to all the mains? anyone know how much main and bigend bearings are likely to cost? and anyone know the sizes? maybe i can source them before i take it apart and do it all in one go
regards SUpratoy

[damo_mk3]

anyone know how much main and bigend bearings are likely to cost?
regards SUpratoy

i payed £180 (ish) for the lot and regride polish the shop i took it to sorted the size's i need so can't help there, and im not shore u can take the sump off with it all still in the car! but some one may prove me wrong

damo

[Lofty]

The sump can come off with the engine in the car but in the long run it is better to remove the engine. In order to remove the sump you will have to raise the engine and lower the crossmember. Also you might have problems keeping everything clean whilst working under the car.

[Sean]

:action-sm :action-sm hello and welcome

[torque of the devil]

oil pressure is the same as mine which is acceptable. the dials can sometimes being innaccurate. with a straight through exhaust where cats are removed gives around 30 bhp and the turbo can be turned up. mines at 12 psi. a safe level for the turbo.