Outer Limits 4x4 Board

hey guys,
question for the knowledgeable souls on the board.
i pulled the turbo off my ute last night as it needs to go to the doctors (and trying to find a rear housing is another story in itself)
and i put the original manifold and exhaust back on to the first join, the one along side the gearbox and thought i might through the EGT gauge on there just to see how it goes without a turbo.

with the turbo which is slow to spool, and makes crap boost, the EGT very rarely hits 500, let alone 550. also runs LPG while on boost.
to get those temps i need a hot day and a long drive, and then plenty of sustained load to hit 550 unless i really work it, but im talking about normal driving.

so now that its N/A again, no LPG, ive seen it hit 640 degrees on the gauge without effort still climbing, and im backing it off now.

im just wondering, what exceptable for a NA TD42 in terms of EGTS? as my post turbo temps getting up to 550 were high, so i thought that 550 NA would be bad too/

EGT reading is taken where 6 becomes 2, just below the flange in the manifold.

cheers, andy

love ke70 wrote:hey guys,
question for the knowledgeable souls on the board.
i pulled the turbo off my ute last night as it needs to go to the doctors (and trying to find a rear housing is another story in itself)
and i put the original manifold and exhaust back on to the first join, the one along side the gearbox and thought i might through the EGT gauge on there just to see how it goes without a turbo.

with the turbo which is slow to spool, and makes crap boost, the EGT very rarely hits 500, let alone 550. also runs LPG while on boost.
to get those temps i need a hot day and a long drive, and then plenty of sustained load to hit 550 unless i really work it, but im talking about normal driving.

so now that its N/A again, no LPG, ive seen it hit 640 degrees on the gauge without effort still climbing, and im backing it off now.

im just wondering, what exceptable for a NA TD42 in terms of EGTS? as my post turbo temps getting up to 550 were high, so i thought that 550 NA would be bad too/

EGT reading is taken where 6 becomes 2, just below the flange in the manifold.

cheers, andy

Does this really surprise you at all ?

You have taken off your turbo which pushes air into your motor and your vehicle is tuned to run with a turbo hence more fuel hence when you push it your EGTs are going to come up...

I would suggest you back the fuel off a bit if you want your engine to survive.

to answer your question same applies if your EGT's are getting over 550 your gonna cook the motor EGT's are still EGT's the higher they are the worse for your motor, your turbo acts as a cooling device when fitted.

550 post turbo is pretty hot anyways. (add 100 degrees for post turbo). I'd be leaning it up a bit.

We have seen up to 750c on my shorty before a turbo was put on. Remember, egts pre turbo are allowed to go to 750c. If no turbo is there, its still 750c. The turbo consumes heat to work as well as adding extra air. Fuel is then adjusted to suit. if you were to monitor a/f ratios, you would find you are probably running richer than with a turbo.



andy

weeman wrote:
Does this really surprise you at all ?

You have taken off your turbo which pushes air into your motor and your vehicle is tuned to run with a turbo hence more fuel hence when you push it your EGTs are going to come up...

I would suggest you back the fuel off a bit if you want your engine to survive.

to answer your question same applies if your EGT's are getting over 550 your gonna cook the motor EGT's are still EGT's the higher they are the worse for your motor, your turbo acts as a cooling device when fitted.

i knew the temps would be higher, as i know the turbo will reduce the EGTS, it was the amount they went up by, i could go 700+ easy on a moderate hill, its hitting 500+ just around town below 2000rpm, 2nd and third.

what surprised me is all the fuel that we have added has been LPG, which as i said, isnt flowing, and a quarter turn on the pump. so whats surprising is how high these temps are for almost standard fuel pump settings. thinking that with big tyres and big loads, ie driving the range or something, the temps would be massive, and most people wouldnt even know.

the turbo will be back on as soon as i can get a rear housing, or maybe a whole new unit...

coxy321 wrote:550 post turbo is pretty hot anyways. (add 100 degrees for post turbo). I'd be leaning it up a bit.

it climbs to 550, you can get any truck to climb to 550 basically if you try hard enough. on a power run on the dyno in 4th i dont think it was going over 450, even after 12 runs..

Dzltec wrote:We have seen up to 750c on my shorty before a turbo was put on. Remember, egts pre turbo are allowed to go to 750c. If no turbo is there, its still 750c. The turbo consumes heat to work as well as adding extra air. Fuel is then adjusted to suit. if you were to monitor a/f ratios, you would find you are probably running richer than with a turbo.



andy

thanks, i thought it could go higher, wasnt sure by how much.
was talking to a quite disliked workshop on these forums today, who told me adjusting fuel by EGTs is just silly, and cant be done properly unless you use a/f ratios.
what are your thoughts on this?
might PM you about the ball bearing turbos



cheers, andy

Dzltec wrote:We have seen up to 750c on my shorty before a turbo was put on. Remember, egts pre turbo are allowed to go to 750c. If no turbo is there, its still 750c. The turbo consumes heat to work as well as adding extra air. Fuel is then adjusted to suit. if you were to monitor a/f ratios, you would find you are probably running richer than with a turbo.



andy

Wouldn't the turbo be a restriction that causes a rise in temps at the manifold. This is just theory on my part.

No Turbo = Higher EGT.. THe turbo dissipates a fair bit of heat I would say 700 degrees is reasonable for an N/A

yeah i think i got it to just under 700 before reaching the top of a hill.
didnt get a chance to really test it on a long hill, just glad to be putting the turbo back on tonight, what a mess its been.
spent today driving with just the turbo manifold. oh the noise