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Discussion Starter #1
So I'm doing a full rebuild on my Ga16de, and all I can seem to find is stock replacement parts. Has anyone used or found aftermarket pistons or rods? Or head parts other than the camshaft? Jim Wolfe makes a camshaft and flywheel, which may or may not go in depenging on budget (hopefully), but that is absolutely ALL I can find for internal upgrades on this engine. Anyone know of any other websites or companies that make upgrades for this engine?
It would kill me to put all stock parts in after all that work.
 

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Might I suggest that you port your head and intake manifold?

ARP studs aree available for all vehicles and will make your motor a tank. Since the stock connecting rod bolts are only torqued to about 26 pounds, it's not a bad idea to get some studs in your bottom end. The top end is probably fine, but if you got the cash and you want a bulletproof GA16DE go for it. Plus, it would be so sick to see a studded out GA16DE... dropping the head over those beefy studs...

Another good idea is to get the blocks deck ground down. This will increase the compression ratio and squeeze some more ponies out of the motor.

Underdrive pulleys are widely available for a bunch of different vehicles.

An MSD ignition coil helped me out in regaining some lost HP on my GA16DE. MSD ignition coils are only about $40 and they make a world of difference.

Get an SR20DE throttle body from a junkyard and port out the intake manifold for a decent gain.

Finally, advance the timing a couple degrees and you should be ready to go.

Unfortunately the GA16DE didn't get as much credit as the SR20DE from aftermarket companies, but the stock components still harbour a lot potential. You can bore out the block, grind the deck, and get some titanium oversize valves in the head after a 3 angle valve job and those crazy Jim Wolfe cams and push mad horsepower.
 

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Discussion Starter #3
Wow, I really don't think you missed anything there, thanks alot for the tips. I thought about boring out the block, but what is grinding the deck? Would that effect a turbo if I can throw one on later? Sorry for my ignorance :) but you seem to know alot of the unasked questions.
Thanks,
Jake
 

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Another good idea is to get the blocks deck ground down. This will increase the compression ratio and squeeze some more ponies out of the motor.
You can't remove much from the deck. Not enough to make a noticeable increase in power. The stock GA16 pistons are nearly flush with the deck, so milling off too much will result in piston-to-chamber contact.

If you want more compression, go with custom high compression pistons. I had some custom 10.5:1 pistons made years ago by Venolia. They were still slightly dished BTW, so you can imagine that with domes you can get substantial compression increases. 13:1 would be easy, but you'd need supporting mods to work with that.

11:1 could be used and still tolerate pump gas, if you had cams to go with it (the increased overlap would negate some of the cylinder pressure increases from the high compression). We ran the 10.5:1 compression with pump gas and modest cams, plus 5° more baseline timing and it never pinged. The combustion chamber design seems to be extremely knock-resistant.

IMO, the best places to make power with the GA16DE are:

*Professional head work, concentrating on the head's poor exhaust flow characteristics. Bigger (custom) valves, although expensive, would wake this engine right up.

*Cams. Even the Jim Wolf cams are pretty darn tame. There's a lot of power potential with appropriate cam profiles, probably somewhere on the order of .425"-.440" lift and 240° @ .050" duration (about 280-290° advertised depending on the lobe's profile).

About 6 months ago I helped a friend out with a Subaru EG33 engine. Had some cams custom welded and ground, and I ported the heads. The engine picked up 71 whp with no other changes. I think this shows that most production cams are extremely modest. Those stock Subaru cams were .280" lift and 198° @ .050", we went with .450" lift and 244° @ .050" duration. It literally added almost 2000 rpms of usable powerband to the engine (revving to 8200 rpms).

*Compression ratio increase...works in conjunction with and compliments the cam upgrade.

*Proper 4-into-1 long tube header and good exhaust system.

FWIW, you'll never make really strong power increases with modest bolt ons with this engine. Gotta go custom at some point. It's not a bad engine design, but we have to remember it was designed as a cheap, mass-produced economy car engine. Nothing else, no aspirations of FIA domination, just a grocery-getter.

Bob
 
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