How to build a relatively inexpensive, reliable, 'powerful' 2.0 8v.

[Prof315]

Are these gauges the common way to tune? or are they just toys. Most of the posts I see the mention of a chip upgrade. It would seem these are blind upgrades unless you have a measured record of what the fuel is actually doing. I understand that you can use a PC to connect to the OBDI &II computers to read the air fuel ratio.
I know that with MegaSquirt you need to use a computer to read the air fuel ratio among other values to develop the tune. But the guys with MegaSquirt running are the only ones who talk about using the air fuel ratios in their tuning.

I consider a wideband O2 sensor an essential tool to tune with. Doesn't matter if it's carbs, CIS or standalone. With MegaSquirt and a wideband the tuning process has become crazy easy. TunerStudioMS (one of the tuning software programs for MS) has an outstanding autotune feature. Set up your Air/Fuel ratio target table, turn on the autotune function, and go drive or strap it to a dyno. Now this only tunes FUEL, you still have to deal with tuning spark tables but it still makes things much simpler.

[Hurt]

. Another thing i had was a vacuum gauge. Sounds silly, but it also aids in any potential issues you might encounter.

I agree with that. In my Track Coupe, it had the centre console made into a gauge cluster of sorts. In it are:

Oil PSI h20 Temp Wideband
Vacuum Oil Temp Volts
Pyrometer Shiftlight

The vacuum gauge helped on one occasion, and I liked seeing it go zonkers when I floored it.

[911_fan]

I originally installed it for a ram air setup I was testing. Never saw any positive pressure. Not enough funds to go any further, plus ram air only takes effect above 110mph. (slightly unrealistic in every day driving conditions lol)

[Hurt]

I originally installed it for a ram air setup I was testing. Never saw any positive pressure. Not enough funds to go any further, plus ram air only takes effect above 110mph. (slightly unrealistic in every day driving conditions lol)

110?! I thought it was much lower than that. No positive pressure at all at around 40-45? I've seen so many different ram-air set ups on track cars. I'd imagine they'd be better performing.

[root beer]

I saw gains with a headlight intake, and I only trapped 111 2x, and 112 once.

But yea, the dailyability thing...

[911_fan]

Gains as in an increase of available air into the intake, absolutely. I witnessed a considerable difference on the dyno with this set-up. (the pics were actually the morning of my 142whp dyno session.)

But as for building positive pressure into my intake manifold (boost), no dice. I never saw any sustainable positive air pressure on my vacuum gauge. And if there was, it was so minimal that I didn't see it. Positive boost pressure is less than 1% at hiway speeds. Had I more access to welding materials and more budget, I probably could have fabricated something a tad more useful and completely sealed.

Through all the research I did, the one I was most interested in was a motorcycle magazine test of 5 bikes which used ram air to boost their top end performance. Test were done on a dyno with the aid of some pretty big fans. Although the fans didnt provide the necessary air flow that simulates 100mph+ speeds on the open road, it was enough to test the ram air capabilities of their air boxes and see the gains as a result. It was around 110mph at which outside air ramming into their air boxes overcame the pumping forces /air speed of the pistons. But even then, gains were maybe 1-2%. Its not until speeds of 300mph does ram air actually matter. Rolls Royce discovered this in the 1920's. When they adjust fueling for their engine, they saw power increases of 15%. So realistically, ram-air on street cars: Myth. Ram air on race cars: 1, maybe 2% power increase depending on speed.

You will get more power gains by air box volume tuning. Ever wonder why our cars have more torque with the stock airbox than a CAI? Just look at the design; Built in ram horn (velocity stack) and the plastic ribs inside the box structure. All this is to increase air flow into the intake tube and control the resonant frequency of the air. Those ribs cancel out any frequencies at specific rpms to deliver a smooth, not peaky, torque curve. When people start 'shaving' the insides of their airboxes, I just laugh. Or when they remove the entire airbox and slap a cone filter right on the end of their MAF. Again, I laugh.

[Hurt]

Yeah. I'd imagine you'd have to be going pretty fast and have a welded set up for ram air to create any significant amount of boost. I personally hate the whole "ram air" fad that Pontiac started in the 1990's. Ram-Air hoods on the Grand Prix GTP and Trans am, sure. But not on pick-ups, and cavaliers.. I see a ton of cars around here with "ram air" hoods. It's funny that 99% of the idiots who bought them don't even know that they aren't functional.

[Hurt]

Did a little revising/editing, bumping this so people can see it and not start other threads.

[Hurt]

Going to add a forced induction section tomorrow.

[Hurt]

Update: Added information on FI.

[2.slowduo]

Only obd1 ABA have forged crank and oil squirters.
While good for boost not really a forged bottom end

[Hurt]

Only obd1 ABA have forged crank and oil squirters.
While good for boost not really a forged bottom end

They have forged internals.. I didn't say anything about oil squirters, or obd1.

[2.slowduo]

That simply is not true.
This has been good info. But
Obd1 forged crank, forged rods, cast pistons
Obd2 cast crank no oil squirters
Not being a jerk. Just the way it is

[rommeldawg]

mm well which obd2... some had squirters some didnt... i believe it was the aeg that didnt and the later avh and up did. i know my 02 avh engines.. three of them do have squirters... now as for the internals... crank is cast as are the rods and pistons. but according to intergrated engineering the stock crank is capable of 400hp without issue so spend the money on rods and pistons... also squirters can be added

[Prof315]

The forged OBD1 ABA cranks are also about 3 lbs lighter that the obd2 cast cranks.

[Hurt]

[Hurt]

[Hurt]

mm well which obd2... some had squirters some didnt... i believe it was the aeg that didnt and the later avh and up did. i know my 02 avh engines.. three of them do have squirters... now as for the internals... crank is cast as are the rods and pistons. but according to intergrated engineering the stock crank is capable of 400hp without issue so spend the money on rods and pistons... also squirters can be added

This is mainly for ABA MK3 and ABA swaps. Not MK4's.

[Hurt]

bump

[Hurt]

ttt - this thread keeps "OMG 8V FAST PLZ" threads from popping up.

[Hurt]

Bump for the forum's sake.

[MYGTI_MA]

great thread that any noob who wants to mod the mk3 2.0 should/must read.

[Hurt]

great thread that any noob who wants to mod the mk3 2.0 should/must read.

Thanks bud.

[Hurt]

The forged OBD1 ABA cranks are also about 3 lbs lighter that the obd2 cast cranks.

3lbs? Hm.. I wonder why VW didn't stick with them.. Maybe the cost of making them was higher.

[Prof315]

3lbs? Hm.. I wonder why VW didn't stick with them.. Maybe the cost of making them was higher.

It's MUCH more expensive to forge metal as opposed to casting it.

[Hurt]

It's MUCH more expensive to forge metal as opposed to casting it.

The obd1 cars also have a slightly more aggressive cam profile and combined with the forged crank, oil squirters, and a few other subtle differences, they had a 6400 rpm redline instead of obd2 cars that had 6200. OBD1 = lucked out

[911_fan]

The obd1 cars also have a slightly more aggressive cam profile and combined with the forged crank, oil squirters, and a few other subtle differences, they had a 6400 rpm redline instead of obd2 cars that had 6200. OBD1 = lucked out

I don't know where you came up with that hypotheses, but its wrong. Why do you think the OBDI cam is more aggressive? Because it has 1*/2* more duration? Bah...it has a wider LSA and a much shorter lifter than the OBDII cam. Both are designed to match the intake port design of either head to give the same hp/tq figures. Yes, you would see a variance on a dyno if you flipped cams on either head, but its nothing you would feel on the butt dyno. The switch to cast crank, single springs, non-squirters wasn't just about cost, it was also about fuel efficiency. Less rotating mass = more fuel efficient. Which was the sole purpose of the OBDII intake port redesign. Quieter, torquier low end, and better directed the intake charge where it belongs...on the center of the piston. The sacrifice of the intake shrouds was top end power...hence the cam profile difference.

Also the rpm rev ceiling is moot...these motors stop making torque @ 4500rpms. I don't know why anyone in their right mind would rev one of these suckers past 5500rpms.

[Hurt]

the rpm rev ceiling is moot...these motors stop making torque @ 4500rpms. I don't know why anyone in their right mind would rev one of these suckers past 5500rpms.

I was only pointing out why the redline on the OBD1 cars (bubble clusters.) was a little higher.

[Grenade Gavin]

Bump to first page. This is an excellent thread with great info.

[Hurt]

Bump to first page. This is an excellent thread with great info.

Thanks, bud.

PS: Looking into making a good head-work section.

[Hurt]

Bumping this for the forum's sake. To a MOD: Should I bother re-posting this in the MK3 forum? It's tailored toward ABA's, and a ton of "OMG 8V FAST PLZ" threads pop up there a day. I think it'd help, but I'd rather have a mod tell me. Thanks, I really hope everyone who uses this gets useful information. If you have any ?'s, feel free to PM me or post in this thread, I check it daily.

[FourEyes]

PS: Looking into making a good head-work section.

Looking forward to this. I really want to learn more about headwork..

[GloryFreak]

Same here! Love my little aba daily

[Hurt]

Looking forward to this. I really want to learn more about headwork..

I've been trying to find some good information, but I've always sent my heads to a machinist friend of mine.

[FourEyes]

I've been trying to find some good information, but I've always sent my heads to a machinist friend of mine.

You should talk to him.