4AGE reliability on oversize piston

[benjaminn78]

Dear forumer sifu,

since my engine still pending at workshop waiting for the forged piston, i would like to ask, there is maximum 82mm oversize piston produce by TODA that has been use by some forumer, and there is no problem with the relibility. Now i got the news that there is a forged piston size 83mm for 4AGE. i would like to know has anyone who has rojak their 4AGE with other car with 83mm piston? mind to share your experience?..

 

[nappx]

aiyah...83mm...first at all i never do...even oversize piston..just run stock piston...what i can think is..about the engine reliability...how about block itself..the distance between hole..

good discussion here..

 

[scottwrx]

my fren tried a 83mm piston from mazda on 7age, pump up to about 1930cc facing some cooling issues, need to change double layer radiator and add oil cooler as for clearance between holes, no prob.., if u wanna play oversize piston, better install a water temp meter with warning beep.. to be on the safe side mah..

 

[benjaminn78]

i already have the oil cooler and 2 row aluminum radiator...so beside cooling, have you friend facing other problem?

 

[1JZtezza]

Hmmm very interesting topic...anything is possible...devil is in the details.

Can not remember if you could just bore it out or re-sleeve original block.Anyways make damn sure it is centred correctly over each con-rod journal on the crank.This is actually the hardest part;to get a machine shop to do to very fine tolerances.

Next is the piston pin hole relative to original piston.Two ring(racing) or three rings.If can, get the three ring piston.

What head?16v or 20v and whether the pistons got the relevant 'cut out' for the valves and got to check for valve clearance;more so if you are using hi-lift cams.Want to be greedy go 304/304 but stay standard lift(16v) plus valve springs.TRD bearings

Balance all the stuff,increase your injectors which means add performance ECU.PNP, bigger extractor

Remember change con-rod bolts.

11000rpm screamer on the way!!!good luck!!!

---------- Post added at 09:48 PM ---------- Previous post was at 09:46 PM ----------

ps. get the TRD oil pump(drive and driven gear).Dry sump is obviously better but damn expensive.

 

[benjaminn78]

ok, this is what i have done as far....

Head (Has complete)

-PNP head
-TODA 288/9.2 CAM (IN/EX)
-TODA Valve Spring.
-Reshim
-TRD metal head gasket (if state on 82mm piston), other wise need to custom 83mm gasket. also from WESLEE RACING.

Block (still decide which piston to be go)
- Ori 20V BT block bore to 82mm or 83mm....
- WESLEE RACING oversize forged piston ( still decide 82mm 0r 83mm)
- AE101 conrod with ARP bolt
- KINGS Racing main and conrod bearing
- Crankshaft to be balance after putting all the piston and clutch.
- WESLEE RACING lighten pulley...5 pieces per set.

so any other sifu can share the oversize piston experience?

 

[TRD.AE92]

bro... I done this before...
4AGE + TX3 piston (83mm)..
Long lasting? ermmm... I don't think so.... I use only 3 month, then the block cracked.... Everyday drive about 100km...

My mechanic car... Using this piston as well, but end up... block cracked in 6 month.

So... you still want to go for it? Think by yourself la... no offence


But I do have use the 4AGZE with 82mm piston, and boosting 1 bar with SC14 charger... and even used for 4 year without any problem occur.

 

[benjaminn78]

as the conclusion, seem 83mm cant be last long due to thinner wall block crack...thanks sifu,

 

[linkeong]

According to one of my mech he said 83mm should be able to last long but your ECU tuning need to be ultra fine. There is one in Perak with 83mm, sometimes he goes to dato sagor track

 

[benjaminn78]

According to one of my mech he said 83mm should be able to last long but your ECU tuning need to be ultra fine. There is one in Perak with 83mm, sometimes he goes to dato sagor track

Wat aftermarket ECU did he using?

 

[TOMee90]

ok, this is what i have done as far....

Block (still decide which piston to be go)
- WESLEE RACING lighten pulley...5 pieces per set.

so any other sifu can share the oversize piston experience?

hi bro, wud u mind to tell me, how much it cost u for d WESLEE RACING lighten pulley? n where can i get it?

thankz.......

 

[benjaminn78]

hi bro, wud u mind to tell me, how much it cost u for d WESLEE RACING lighten pulley? n where can i get it?

thankz.......

you can check through this link

http://www.zerotohundred.com/newfor...04104-performance-pulley-for-4ag-engines.html

http://store.keganiautotech.com/index.php?main_page=product_info&cPath=2&products_id=91

 

[nappx]

got diff or not if used svt or bt block

 

[linkeong]

Dont bother with the WESLEE pulleys, they are exactly the same ones with GPW. Same weight same material even looks very very similar and you can get it for cheaper at subang. That guy uses emanage ultimate only if not mistaken, need to reconfirm with me mech

 

[cybtech]

my point of view... dun be too greedy...
if anything happens... (touch wood) you'll regret it...
just go can move, have fun driving, and save money... economy crisis here...
of course, unless you're going to track la, using engine pakai buang.....

 

[TRD.AE92]

I will disagree with you....
I do use this with Haltech Interceptor but... end up can't use more than 3 year if daily use! Unless that car is 24hour kept at home and only come out with special purpose only la..

 

[1JZtezza]

I will disagree with you....
I do use this with Haltech Interceptor but... end up can't use more than 3 year if daily use! Unless that car is 24hour kept at home and only come out with special purpose only la..

Lost me here,problem is the ECU or piston?

Frankly I dont know much about Weslee racing pistons.Are they 2 ring or 3 ring(piston rings).2 ring ones are the racing pistons.They dont last and there is a lot of oil lost through 'blow-by'.Unless you wanna do rebuild say every 1000km or so.Mahle pistons got good reputation but dunno if you could get them or what the cost.

Correct me if I am wrong.BT supposedly 'non interference' engine.But you are using 288 Toda cams with 9.+ mm lift.To be safe you may need slightly thicker head gasket to make sure valves dont kiss piston.get your shimming and cam set with engine out of the car.Then you can handturn the crank to make sure the valves dont kiss.Also test when vvt kicks in ie advance the cam to simulate 35 degree BTDC.

This the tricky part:standard cam peak is 120 degree ATDC(inlet).Check your spec sheet for Toda cam where the peak is.Could be between 105degree ATDC to 120 degree ATDC.Let us say its 120 degree ATDC; so below 4400rpm its suppose to open 24degree BTDC which implies when vvt kicks in it becomes advanced another 30degree ie 54 degree BTDC.
Personally I have a distrust of adjustable cam pulleys although others have success in them.Prefer the old TRD 16 valve pulleys which means sacrificing the VVT.However the BT head has better flow than the 16valve.

Any other sifu with any experience; VVT and high cam???

Cheers and good luck.

 

[TRD.AE92]

sorry which I made you blur...
The problem is at block not the ECU, tuning and piston itself...

 

[cuscostrutbrace]

I have heard one guy running 83mm in 16v 4AG and dont have problems with it.Its Nissan CA18 N/A piston.Toyota block is quite strong,i guess there must be something wrong with the installations(machine shop process),and tuning..if all things are correct,should'nt be a problem.

Good luck

 

[1JZtezza]

The moral here is most mix and match can be made to work;however you got to be damn meticulous with the assembly and installation.

Even NASA space rocket was brought down by a simple O ring!!!