4AGE 16v compression questions

[pc]

ok.. this is a few questions
1) what is the standard compression on a 4age 16v N/A ?
2) what is the standard compression on a 4age with the forged pistons ?(bigger dip in top of piston)
3) what is a relativly safe upper limit for compression on a N/A engine with forged pistons but without other expensive/fancy internals?
4) and... assuming a 0.5mm head gasket, how much would have to be taken off the head when using said forged pistons to get to compression in question 3

[RedMist]

1. Depends on the 4age, your bluetop is 9.4:1 standard. The redtop smallport is 10.3:1.
2. Depends totally on the forged pistons. Forged pistons come in different crown shapes to give you more or less compression.
3. Depends totally on fuel. If you run race gas such as 76 you should get up to 13:1 compression. Methanol you can run up to 14:1. However this is an estimate, you may get as low as 12:1 compression and have detonation problems. It all depends on how you build your engine, how good the pistons are, how well you work the head etc.
4. Can't be predicted. Totally depends on what forged pistons you buy, how big a projection you have into the combustion chamber to begin with.

5. What are you trying to do?

An engine is a sum of its parts. Rasing the compression isn't going to give you a massive HP increase. You may find that increasing compression increases detonation, you alter timing, and loose HP.

[pc]

5. I have a bunch of parts and am getting a reconditioner to put it together with appropriate machining being done. The goal is to have a reliable N/A engine that will run on the factory computer. I will be getting cams reground and raising compression, can't remember cam specs but I think it was 264degree duration. probably done by kelford.
I am also contemplating getting port/polish done, but don't know if it's worth doing as yet.
Will be running engine on 98 octane (from BP)

This is for race (without spending lots of money)

[CAMB01]

What Reconditioner are you taking it too?

[JT]

5. I will be getting cams reground and raising compression, can't remember cam specs but I think it was 264degree duration. probably done by kelford.
I am also contemplating getting port/polish done, but don't know if it's worth doing as yet.

The ports are already too big so no porting is necessary! Do a search on here for 'flow AND 4age'.

Here's some info on cam's for a 4age..

viewtopic.php?t=5735&
viewtopic.php?t=11310&

[pc]

Couldn't find anything relevant on flow AND 4age. Has anyone here done port work on a 16v head, and verified results with dyno plots?

I looked at some cams a guy was selling last night and the lobes had extra bits welded on and then they were re-ground. They had been in a car and the lobes had started chipping/cracking on the ends. It's put me off welded ones.

Anyone got any other ideas of relativly cheap mods to do to the engine that will give more power on factory ECU? might as well do it all at once while it's apart.

What Reconditioner are you taking it too?

Kerry Lindsay in Upper Hutt

[CAMB01]

Oh ok coz i work for Kerry Lindsay in Porirua.