4afe A.R.P head studs

[mega4a]

on the weekend got my car dyno tuned 240hp at the wheels and 275 ft pounds of torque at 18 psi was wheel spinning 3rd on the dyno so to get a good dyno read out we decided to rape 4th gear so it wouldnt lose traction on the dyno so raping 7000rpm in 4th gear on 18 psi the head gasket blew water went every where lol. we got an good dyno read out though lol.

we think the standard head bolts might have stretched under that much combustion and lifted the head up. has anyone had this problem before? how much boost do the torque to yeld bolts handle?

i got a steel trd head gasket.


but my real question is do 16v 4age A.R.P head studs fit 4afe? from what i have google they do but just want a second opinon from you guys and what is a good head gasket to use a cometic one? or go with another trd one?

[d1 mule]

I know willie, aka 4agtepwr had that issue when his mr2 was on the dyno max power run, 555whp.

donno if they worried about fixing it tho, just ran it at lower boost, was like 30psi or something to do that

[DexGT]

ToyoDIY says part numbers are the same so should be the same.
When you say TRD headgasket is that standard thickness or the thin one? , cause the thin one would raise the compression which wouldn't help.
Having said that my car has been running 20psi boost for a few years on a standard headgasket and torque to yeild standard bolts without issues , I think you might have another issue , did you machine the head / block when you fitted the headgasket ?

[mega4a]

ToyoDIY says part numbers are the same so should be the same.
When you say TRD headgasket is that standard thickness or the thin one? , cause the thin one would raise the compression which wouldn't help.
Having said that my car has been running 20psi boost for a few years on a standard headgasket and torque to yeild standard bolts without issues , I think you might have another issue , did you machine the head / block when you fitted the headgasket ?

i guess if the part numbers are the same then they will work.

ummm trd head gasket from north shore toyota the 0.8mm one that was the thickest one they did i thought. the block was decked and the head was machined yes.

i just think 4afe head can't handle that much boost maybe?

[loose_unit]

The figures look pretty similar to what a similarly built 5efte would make, and the designs of the two engines are pretty similar bar the little bit extra capacity in the 4a. You are getting to the point where you will probably start coming to a bottleneck. The factory Inlet on 4e/5e is usually the first bottleneck and id imagine it will be the same on the 4afe.
Looking at the build the turbo looks like it might be a limiting factor also.

[DexGT]

Are you running standard pistons , cause with a 0.8 mm headgasket (standard one is 2mm i think) decked block and head you will be running very high compression which would cause the issue you had.

[loose_unit]

Probably not too bad with the 8.0 pistons in it, I think factory is 1.2mm?
Are you still running the starlet injectors? Because you are doing pretty well to make 240hp on 295cc injectors.

[allencr]

i just think 4afe head can't handle that much boost maybe?

Much more likely to be an instillation problem, lube, re-torque or too little torque then an inbuilt factory problem with a big hunk of aluminum.

[mega4a]

Are you running standard pistons , cause with a 0.8 mm headgasket (standard one is 2mm i think) decked block and head you will be running very high compression which would cause the issue you had.

the pistons are 8.0 low compression ones from an aw11 super charged motor the compression should be low.

[mega4a]

Probably not too bad with the 8.0 pistons in it, I think factory is 1.2mm?
Are you still running the starlet injectors? Because you are doing pretty well to make 240hp on 295cc injectors.

running 565cc pink injectors from suby.