Is this the beginning of a BHG?

[1986.5supra_kid]

Hello fellow members,

I have noticed after doing my 2jzge-t swap that coolant will come out of the overflow bottle and onto the windsheild when under 16psi for extended periods of time like from a dig to max speed on the track or long hills in full boost. i currentally have a stock cooling system and i have a koyo rad in my garage for when i get around to fitting it but i have beeing reading the trsm that the timing being retarded can cause excessive heat produced. i have a standalone and the tuner was all about bering "safe" so im wondering if my tune could be to retarted during boost. the engine has a 2.5mm metal cometic head gasket and arp studs. i hope the HG isnt bad but i was told you dont need to retorque studs to maybe this was wrong. not sure just asking the professinals here.

thank you!

 

[hvyman]

Studs still need to be torqued. If you reuse them they have all ready had enough heat cycles and have stretched. New ones need to heat up and cool down a few times and then be checked.

So if you havnt done that I would check them and if any are loose do the hg.

If there tight do a compression test or leak down test and block test.

Also might be good to pressure test the cooling system and make sure there are not any other leaks.

 

[Radial]

Hg probably needs a re-torque as mentioned.
A Very low timing advance can also cause overheating, but your tuner should have seen it on the dyno as it affects power and tq significantly.
How is your timing map at 16psi? 5*ish?

 

[1986.5supra_kid]

the last time i did a compression test it was 120 psi iirc on all cylinders. ill check again today. as for checking the head studs i just do the 100ftlb check?

leak down will be checked this friday and same for pressure test on coolant system, i have to buy those tools

 

[1986.5supra_kid]

View attachment batlgroundnot sure.01V24.cal

View attachment BatlGround.01V24.cal

i think this is my most recent tune and it looks like ill have to do all of the diagnostics friday. i need to get some rest. btw im thinking about buying the harbor freight leak down and radiator tester. any thoughts?

http://www.harborfreight.com/cylinder-leak-down-tester-94190.html

http://www.harborfreight.com/radiator-pressure-tester-kit-69258.html

 

[1986.5supra_kid]

not to be post happy but ive been reading some supraforum posts and im pretty sure i put the overflowcap on right but ill check that too. the thermostat and rad cap are relatively new as well. now to search burping the coolant system.

editurchased the spill free funnel for burping the system.

 

[Jtsan]

View attachment 69883

View attachment 69884

i think this is my most recent tune and it looks like ill have to do all of the diagnostics friday. i need to get some rest. btw im thinking about buying the harbor freight leak down and radiator tester. any thoughts?

http://www.harborfreight.com/cylinder-leak-down-tester-94190.html

http://www.harborfreight.com/radiator-pressure-tester-kit-69258.html

I bought the harbor freight leak down test about a year ago. Only problems I've had was the gauges were shitty out of the box. I replaced them and they are still good. Actually just used them this pass weekend.

Can't say too much about the harbor freight pressure tester. Never used theirs before.

Good luck with the trouble shooting and let us know what you find.

 

[Radial]

View attachment 69883

View attachment 69884

i think this is my most recent tune and it looks like ill have to do all of the diagnostics friday. i need to get some rest. btw im thinking about buying the harbor freight leak down and radiator tester. any thoughts?

http://www.harborfreight.com/cylinder-leak-down-tester-94190.html

http://www.harborfreight.com/radiator-pressure-tester-kit-69258.html

Advance is definitely not retarded in any of them. But none of the maps looks good IMO.
I'm quite a noob on tuning yet, and have no experience with AEM (except a bit with the software), but i'm seeing crazy looking maps... and especially for a N/A setup.

Example from BatlGround.cal:
- 19-22* of spark advance from 3000rpm at 19PSI... on 92 pump gas? Sounds like a upcoming "knock-out" destruction to me. Your knock control is activated, so you better hope it works
- A fuel table that actually leans out from 5500 at WOT...(The AEM Fuel-numbers does not say anything to me, but the curve looks strange).
- A fuel and spark sized up to 60psi on a car that barely touches 17psi? This is not after the tuning handbooks, as it makes corrections very rough. Maps are to be scaled for the intended use, so your map should stop at ~20-22psi.

On "Not sure": (I hope this map is in use)
- Ignition looks way better (except at idle, with a sudden drop in timing to 15* etc), and Fuel does not lean out that hard after 5500.
- Scaling is at 30 PSI, and thats more like it... Knock settings looks better too.

For reference only, a "safe" map for a 1JZ is 10-13* BTDC on 16PSI with stock compression and COP ignition.
This is purely my view on the maps. Others may say different.


But you do not have a sloopy timing, thats for sure.... so start with pressure-testing your cooling system, re-torque HG, Check for leaks etc.
A JZ needs heavy duty cooling for Race applications though, so big ass radiator is required even on a stock JZ.... The more oil coolers, the better as well.

 

[rakkasan]

go to NAPA and buy their BHG test kit. It's a chemical test and will give you a definitive answer. Blue = good, green = bad.

 

[525gte]

I had this happen. It was a bad sealing surface on the rad cap..

 

[f00g00]

If your turbo is water cooled then that would put a lot of heat in the cooling system when running extended boost. The stock cooling system might not be able to keep up with that.

 

[1986.5supra_kid]

Thanks radical: i would love to understand tuning as well.
525gte: im hoping its a bad rad cap
rakkasan: ill look for it online.
jtsan: what guages did you use to replace them? i was thinking 2 0-100psi that way its easier to get a precentage. so less than 15% would be a healthy motor with 10k miles after rebuild?
f00g00: turbo is only oil cooled,engine oil has no cooler either. its a stock 2jzge with the mods in signature
i hope the rad cap is leaking and not HG, but if not ill put the TT HG on this time instead of the 2.5mm and start my phase 2 of the build

 

[f00g00]

What turbo? I am thinking of oil cooled only when I go single because mine overflows when boosting a lot with the stock twins but temps here are 40 °C plus and I was planning on adding an oil cooler when the pea shooters come off.
I would be curious though how much having hot oil adds to an overheat condition.

 

[1986.5supra_kid]

I have a Cummins turbo. Hx35 really a hx40 or super40 would have been better. $200 turbos that do 400-500hp on pump gas.

 

[Jtsan]

I replaced them with 2 100psi gauges. Make sure they are 1/8 npt. I forgot where I got them but I'm sure you can source yours locally. Then hook it up and do the math. Turns a cheap tool into a pretty good tool for the price I think.

 

[1986.5supra_kid]

well the rad cap stopped the overflow bottle from overflowing and draining the rad. but i still smell sweet smell under boost for extended periods of time. so i guess this means the stock radiator is not up to snuff for cooling?