Oversize block

[benjaminn78]

hi,

have anyone sifu here done this b4?

-increase CC... using 4AGE head + 7A 1.8CC block..... or
using 4AGE head + 4AGE block (bore block from 81mm to 82mm ) +oversize piston...

which would better?...i know the 1st one is cheaper...... the second one....TODA oversize piston will cost u RM3000......:Not_Impressed:

 

[azuaneman]

lastime, what i know la. one of the formen in melaka here use NON-TVIS 16v engine in his LE, then he upgrade to 1.8 block (7A).. and use camry piston, i think... but donno which version.. try ask sifoo here.. :D

 

[normality78]

i also heard before about camry piston thing. but dunno anything about it. also heard plp saying about using camry TB which is much bigger. syaing all the bolts and nuts and sensors are identical as 4A one.

 

[turbo10]

i am no sifoo but would like to contribute.if bore to 82mm not much displacement increase.what if 7age+82.5mm toda piston+argo 7a rods...i think mebbe could go nearly 1.9L already.if u go for 7age, the high revving nature of a 4age will loss already coz of the longer stroke.shift point mebbe decreased a bit but if paired with high profile cams we can play with the power band to shift the power to top end and u still got enough low end torque due to increased displacement.some says the rods of 7age are weak for higher revs, it's true but if use under 8krpm i think it's still safe coz i've seen some daily driven, abused blacktop with 7age setup.depends to the driver's liking.if i got the money i would go for 10000 rpm 200hp+ 4age..:X-: but it could cost me a bomb.many2 sifoo here got 7age even 7agte but they low profile only.i'm just a wanna be only :mouth_closed:

 

[normality78]

only toda got 82.5mm piston?

 

[benjaminn78]

i tot TODA only until 82mm......82.5mm piston from what car????

 

[benjaminn78]

i think TODA only have 82mm,...may i know 82.5mm is from what carr?

turbo10,

i know bore from 81mm to 82mm is not much increase displacement, but compression compression increase a lot if match with metal gasket.....

 

[benjaminn78]

i think TODA only have 82mm,...may i know 82.5mm is from what carr?

turbo10,

i know bore from 81mm to 82mm is not much increase displacement, but compression increase a lot if match with metal gasket.....

 

[SmallFry]

bro... wat about 7AG's crankshaft only ?
4age 20 valve wit 7A's crankshaft ...
both crankshaft different rite ?
any comments to this ?

 

[turbo10]

my bad..toda max 82mm only..i'm mistaken with the max bore for the 4ag block 82.5mm..mebbe some went to 83mm but not recommended due to the sleeve thickness issue.sifoo normality..i just name one, mebbe should put there for example..lotsa other guys use wiseco, cp, je..i dunno mebbe more..i admit, i just use the standard 81mm x 85.5mm 7afe bottom.i dont have money to buy those fancy parts..sorry for mistake done..just wanna share my knowledge.thanx

 

[normality78]

huh? since whn i bcome sifu? later i bcome laughing stock

 

[SmallFry]

bro turbo10 .. u runnin on 7A block + 4A head ? turbo or N/A ?
wanna know is rojak like dat for N/A torque ok or not..
just 7A crankshaft itself only wat u think ?

 

[otismummum]

I just wanna share my friend experience. BT block bore 1mm bigger then change oversize piston. Pick up good but no end power. means rev untill 5k rpm then power loss liaw. F.Y.I. with toda high cam etc. 1 month later one of the piston GONE. dunno, maybe that guy always racing........

 

[normality78]

care to share what piston is he using?

 

[turbo10]

bro turbo10 .. u runnin on 7A block + 4A head ? turbo or N/A ?
wanna know is rojak like dat for N/A torque ok or not..
just 7A crankshaft itself only wat u think ?

currently using 7a block + 4ag bigport head..previously running sc14 now running trust td06-17c turbo..currently in build up process.using 7a block + conrods+crank.a fren of mine using 7a block + 20v blacktop 4ag head.low to mid range torque can feel significant improvement of torque but no dyno sheet to prove it..just butt dyno..only managed to try with other similar car with 4ag blacktop and the result quite amazing.both engine have stock head internals except one with 7a setup.if using crank only might upset the crank to rod ratio and might end up lower power or the piston height will be an issue.my humble opinion.

 

[caleb_5375]

y tis gud thread stop suddenly....

I just wanna share my friend experience. BT block bore 1mm bigger then change oversize piston. Pick up good but no end power. means rev untill 5k rpm then power loss liaw. F.Y.I. with toda high cam etc. 1 month later one of the piston GONE. dunno, maybe that guy always racing........


i think the reason for the piston kong is coz after u rebore ,change cam or wat part tat having relation wit moving u should give it a time to suit the block...coz after rebore and oversize u terus hantam sure kong coz the metal to metal rubbing...after convertion also dun go so hard...unless u wan overhaul fasfter like me lah...hehe

 

[SmallFry]

1mm ? betta don oversize..

 

[caleb_5375]

hmm after 5k rpm power drop...i also hairan....maybe 7age conrod longer and it need more time to travel compare to 4age ...anyone know y ??? and other 7age also face tis same problems after 5krpm powerloss ?

 

[benjaminn78]

1mm ? betta don oversize..

do u know how big effect only over 1mm??.....

 

[SmallFry]

i know...
if wanna oversize.. might as well hit bigger..
here i see all hittin real big.. 84 above..
but not toyotas..
toyotas wit type r pistons also i've seen b4..