4G93T Rods - Standard V's Forged

[milkandoj]

What turbo was this on out of interst? As you'd know the power you making on 20psi on a TD04 is verry differnt to 20psi on a 16g ect

 

[youda]

you wont get 20 psi out of a tdo4, you would be lucky to make any serious gains with 16psi

 

[to4garret]

you wont get 20 psi out of a tdo4, you would be lucky to make any serious gains with 16psi

you defiantly get 20psi from a TD04. I also agree on a stock GSR there is no more gains after 16psi.

the problem with going above 16psi (1.1pr*) on a TD04 13g is you start moving off the efficiency island, meaning the turbo starts increasing the charge temp greater than if it was "in the sweet spot"

the reason why you don’t usually get greater gains after 16psi is because of the increase in heat in the charge negating the increase in air volume, co-incidentally the increase in heat/expansion of the charge also increase the "boost PSI" as PSI is not a measure of density.

a lot the efficiency deficiency can be alleviated by increasing the cooling capacity of the charge cooler, bigger I/C?

i am not sure where the TD04 chokes, but its not at a measure of PSI, its at a volume of air.

same way in an engine with a good tune the rods don’t bend at a given PSI, but they do bend at a certain power level as you have gone above force required to bend them.


moral of the story, bending rods at 23psi means fuck all if you flow more air at 16psi.


*plucked from thin air

 

[Smutt]

What turbo was this on out of interst? As you'd know the power you making on 20psi on a TD04 is verry differnt to 20psi on a 16g ect

GT2560 (320 HP).... I would have to check the -dash number, but was at the limit of the compressor map (the plus 3 that is)

you defiantly get 20psi from a TD04. I also agree on a stock GSR there is no more gains after 16psi.

the problem with going above 16psi (1.1pr*) on a TD04 13g is you start moving off the efficiency island, meaning the turbo starts increasing the charge temp greater than if it was "in the sweet spot"

the reason why you don’t usually get greater gains after 16psi is because of the increase in heat in the charge negating the increase in air volume, co-incidentally the increase in heat/expansion of the charge also increase the "boost PSI" as PSI is not a measure of density.

a lot the efficiency deficiency can be alleviated by increasing the cooling capacity of the charge cooler, bigger I/C?

i am not sure where the TD04 chokes, but its not at a measure of PSI, its at a volume of air.

same way in an engine with a good tune the rods don’t bend at a given PSI, but they do bend at a certain power level as you have gone above force required to bend them.


moral of the story, bending rods at 23psi means fuck all if you flow more air at 16psi.


*plucked from thin air

Yep... Rods tend to bend at certain power levels or excessive forces applied to them.... a certain "tune" at a given boost will give a certain amount of HP. There are so many variables..

Interested on what turbo's your referring to though.. one will flow more air at 16psi than another one at 23psi that is suited to the same motor. I assume both of these turbo's and pressures are still on the compressor map

 

[Smutt]

Im using factory head gasket and running 32psi making 423kw!

Wow... I stand corrected.. hmm.. ur not running pump fuel tho to get 423 are you....? Will need to re-read your build post Yep... Meth... nice

 

[milkandoj]

Interested on what turbo's your referring to though.. one will flow more air at 16psi than another one at 23psi that is suited to the same motor. I assume both of these turbo's and pressures are still on the compressor map

I think what me and to4garret are trying to get at is it was your power (and state of tune st that levle) that bent the rods not a set boost figure.

Only trying to clear it up is someone reads this with not idea. With this 16psi vs 23psi comparison, pick a small turbo and a big one and they will flow the same but and much differnt boost pressures, if the tunes good each will still bend the rods if its due only to power output. You could have snapped it just as easly with a larger turbo at less boost. Or is you had a smaller turbo, tuned right and intercooler you may have it on fire at 25+ psi and still not bend rods as it cant flow anuogh to make the power. Knock from too much heat and a shit tune is another story.

 

[to4garret]

you got it milkandoj,

comes down to the old garden hose and fire hose analogy,


get a garden hose in the face at 8 psi and you get wet, get a fire hose in your face at 8psi and you get knocked the fuck over!


but we all know that PSI is only a measure of the restriction of the engine right?



Smutt, i wasnt referring to any trubro in particular, but i can think of a few that would out flow a TD04 at 20psi with only 16psi

 

[Smutt]

I think what me and to4garret are trying to get at is it was your power (and state of tune st that levle) that bent the rods not a set boost figure.

Only trying to clear it up is someone reads this with not idea. With this 16psi vs 23psi comparison, pick a small turbo and a big one and they will flow the same but and much differnt boost pressures, if the tunes good each will still bend the rods if its due only to power output. You could have snapped it just as easly with a larger turbo at less boost. Or is you had a smaller turbo, tuned right and intercooler you may have it on fire at 25+ psi and still not bend rods as it cant flow anuogh to make the power. Knock from too much heat and a shit tune is another story.

oh oh... where do i start.. the increased boost gave the extra HP which bent the rod, timing was not touched, AFR's all OK..

HP is dependant on: Engine capacity, compression ratio, RPM, Boost, oxygen content of fuel and air, Tune... did i miss anything...
Anyone of these changes horsepower...
Saying the extra boost bent the rod is the same as saying the extra horsepower bent the rod..
Which is the same as saying the extra rpm caused more load on the rod is the same as saying the extra horsepower bent the rod...

"They will flow the same but at different boost pressures"???? That's not a level comparison.
The only thing that changes comparing a big turbo to a smaller one for a given sized engine up to a maximum rpm value is the position of the compressor map and its EFFICIENCY rating... this difference in efficiency rating is where slight gains from "lower heat" are made..
It doesnt count if your off the map.. then the chosen turbo is either too small or too big..

Have a play with this performance calculator... you can compare up to 8 different turbo compressor maps at once..

http://www.squirrelpf.com/turbocalc/

 

[to4garret]

oh oh... where do i start.. the increased boost gave the extra HP which bent the rod, timing was not touched, AFR's all OK..

yup, so it was the increase in HP cause by the additional boost.

Saying the extra boost bent the rod is the same as saying the extra horsepower bent the rod..Which is the same as saying the extra rpm caused more load on the rod is the same as saying the extra horsepower bent the rod...

yup, piston velocity is commonly overlooked.

"They will flow the same but at different boost pressures"???? That's not a level comparison.

yup, hence bringing up the turbo/boost comparaion because some 18yo numbskull who just brought a GSR with a cheap ebay TD05H 20g will read this thread and run 20psi then ventilate the block.



good to see everyone on the same page though.

 

[youda]

apart from the cheap part. i do intend to run a 20g on stock internals. my hope is, maybe ill squeeze out a flat 12 before i start wearing a piston as a crutch piece when it blows through the block.

lol...........we'll see how i go. after that the 63 goes in.

 

[youda]

good example of engine breezeway.
in this case original owner had a td05 16g 18psi but only had stock cpu and injectors. this is the end result.

 

[3zercrowd]

yup, so it was the increase in HP cause by the additional boost.
yup, piston velocity is commonly overlooked.
yup, hence bringing up the turbo/boost comparaion because some 18yo numbskull who just brought a GSR with a cheap ebay TD05H 20g will read this thread and run 20psi then ventilate the block.

Lucky im not a 18yo numbskull then aye

For everyones info my car now has a 20G on it running 21/22 psi on a stock bottom end and head, tuned last weekend with a healthy "summer tune".
Its not too rich or too lean but about right for these tropical conditions. (as to be expected up here anyway)
For added security however, I have (yet to complete the installation), a water/meth injection kit that I have had sitting here.

Now, we did want to run 24/25psi OR MORE, but we have encounted a few problems which I have been researching a solution for, so we turned it down to the safer level for now. (if you can call it that lol)

Now, call me crazy, but with 8, (now) 7 engines at my disposal, I have no problems grenading the engine now do I? Not that I want to, but if we can get the tune right and have all of the supporting mods (if you have read my members rides thread) then it shouldnt. The current engine wasnt in that bad of a condition to start with and its been going strong for 2 years now, nearing 20psi.


Now referring to the ventilation of GSR blocks being common,it is believed that it is the failure of the big end of the rods grabbing the crank due to bearing failure and/or the piston detatching from the rod at the small end.
Anyway a lot of the time this occurs from some or all of the following: lack of oil lubrication or pressure, over-revving the engine on gear changes, overboosting the turbo WITHOUT being tuned correctly (being done either accidently or intentionally without having certain precautions),potentially causing mr rod saying hello to the outside world. There are others but we could be here all day. We had a huge database of this sort of technical information on the old www.4g93t.net before it was closed Jarred might have something saved on this maybe? *EDIT* he doesnt

FYI, the engine youda showed the nice ventilation pic of, was just cruising at 70km/h when it let go! :huh: so go figure Can happen at anytime.




*Disclaimer*All of the above that I have written about my car in general should be taken from someone who is obviously crazy (not really) and trying something extreme that a READ: NORMAL person wouldnt attempt. IF you want your car as a daily driver or just a little bit of a boost or power increase, you should stick to the proven SAFE levels of what these engines can handle! If you dont, be prepared for failures and breakages, have a LOT of parts available to you as spares, time, paitence, research, money and of course friends and hookups that can help you along the way. OH and this forum B)

Thanks

 

[Smutt]

Love it! "3zercrowd" :thumbsup: others... read his disclaimer again

hay.... why dont you add some toluene to your fuel... works out to be about $4.80 / ltr from a fuel distributer, that may help for the higher boost - detonation etc (mix in 20 - 30 %)