4age 16Valve Block & Head Light Mods

[gepsk8]

so plan is to build up replacement motor for GTI(fxgt) running Smallport 4age

so plan is to run Replace bearings, rings, seal etc,
Block Work
i was looking at changing the crank to silvertop (heard there got smoother surfaces for faster oil draining??)
Silvertop rods lighter
Standard Smallport pistons 10.5
TRD 0.8 Head Gasket to bring up compression
little bit blueprinting
Maybe replace oil pump??

Head Work
smoothing out ports
Bluetop cam Worth fitting?
Hydraulic lifter worth fitting??
Valve Seal, Etc

Any mods people know work or Recommend??

Already Running lighted flywheel

[Crampy]

i was looking at changing the crank to silvertop (heard there got smoother surfaces for faster oil draining??)

Same crank, so no point changing it.

[Mr Revhead]

i was looking at changing the crank to silvertop (heard there got smoother surfaces for faster oil draining??)

thats a new one!

[crispy'86]

Possibly run bluetop cams, i'm not sure if they're any different to smallport ones. I would have thought smallport heads flow well enough, the only reason you'd change the characteristics was if you ran a large duration cam. Somebody reckoned you can shim the 20v oil pumps to give them more/higher flow pressure if you were to replace them. Definitely TRD gasket for a good performance gain, definitely replace at least the valve stem seals. Be worth checking the valve guides too. (Something i just thought of while on this subject, i really should get thinking of that are some bore gauges to do more precise measurements)
What block work would you look at doing? I'd definitely suggest a surface of the block so your gasket seals properly and not have future troubles (a common fault i've found with many of the blocks i've had all of the 4a family

[Bazda]

Shimming the oil pump up does not give it more flow, it just changes the point where the relief valve operates.
The stock valve will open at around 70-80psi. shimming it up will make it open later.

[tsoob]

so plan is to build up replacement motor for GTI(fxgt) running Smallport 4age

so plan is to run Replace bearings, rings, seal etc,
Block Work
i was looking at changing the crank to silvertop (heard there got smoother surfaces for faster oil draining??)
Silvertop rods lighter
Standard Smallport pistons 10.5
TRD 0.8 Head Gasket to bring up compression
little bit blueprinting
Maybe replace oil pump??

Head Work
smoothing out ports
Bluetop cam Worth fitting?
Hydraulic lifter worth fitting??
Valve Seal, Etc

Any mods people know work or Recommend??

Already Running lighted flywheel

what you wanna achieve with your engine mate (power etc)?

what u gonna use it for (drag track?)

[crispy'86]

Shimming the oil pump up does not give it more flow, it just changes the point where the relief valve operates.
The stock valve will open at around 70-80psi. shimming it up will make it open later.

That's one of the more "Interesting what people say" comments, i didn't take that to gospel, just putting it out there as a comment someone reckoned. I wasn't totally convinced it'd not make too much difference to flow.

[gepsk8]

just replacing my tied old motor, in my daily runner. running standard ecu.
wanted to do some small mod to gain light bit more power & reliability.

[escortman]

just get the smallport head tidied up, whack some bluetop cams in (slightly higher lift and longer duration) def makesure to get head skimmed and block decked and use a trd headgaskit

[gepsk8]

Silvertop rods
TRD 0.8 Head Gasket
Bluetop cams
are to only mods people recommend ??

[KinLoud]

Late smallport engines have the silvertop rods from factory.

[Mr Revhead]

^ correct

only engine I would bother changing rods in would be a black top.
especially as your building a road engine

[Quirky]

Forgot where I read this, but Bluetop cams give a gain of 2kw ATW over the stock smallport items, though it shifts the powerband quite a bit...

[tsoob]

Silvertop rods
TRD 0.8 Head Gasket
Bluetop cams
are to only mods people recommend ??

bolt on a turbo is what id recomend

[Dell'Orto]

Forgot where I read this, but Bluetop cams give a gain of 2kw ATW over the stock smallport items, though it shifts the powerband quite a bit...

So effectively pointless then? Would much rather have 2kw less and have peak torque 1000rpm lower.

[ChaosAD]

I'd add ARP rod bolts to the list, and an oil pressure gauge would be worthwhile.

I have read that the blacktop crank is the same part number as the earlier ones, but toyota called for closer tolerances during manufacture. I dont believe it would be worth changing though.

[pc]

I reckon valve grind, new rings & bearings, plane head & block flat, 0.8mm TRD HG.
Check all clearances.

Cheap & reliable, fast enough without spending any real money.

[Mr Revhead]

I'd add ARP rod bolts to the list, and an oil pressure gauge would be worthwhile.

I have read that the blacktop crank is the same part number as the earlier ones, but toyota called for closer tolerances during manufacture. I dont believe it would be worth changing though.

they would change the part number if they changed any aspect at all of the crank.

any part that gets any change, will have a new part number.

and an easy way to check that would be to check the manuals on the clearances and bearing sizes

[ChaosAD]

It is interesting to note that all the late model, large crank pin cranks-shafts are identical, i.e., same Toyota part numbers. However in reviewing the maintenance manuals, Toyota calls out much tighter inspection tolerances in the last generation 20 valve. The obvious reason would be to keep parasitic friction and vibrations to a minimum due to the difference in max engine speed that the 20 valve engines were allowed to turn versus the 16 valve ones.

http://www.club4ag.com/faq_and_tech_pages/4A-GE%20Crankshaft%20-%20Detailed%20Specifications%20and%20Analysis.html

[Mr Revhead]

oh yep, so tigher tolerances for wear in the service book