For various reasons I recently SOLD my 1981 URQ, and have replaced it with a 1993 100 Quattro Avant 2.6 V6 (Manual Shift) with 60K Miles in mint condition. Being spolied by the kick you get from a 2.2 5cly Turbo, when I took the 2.6 out for a test drive I was a bit dissapointed, BUT, I do want to start pepping it up a bit. I have been reading the all the posts about the TB etc.
Q: What's the best thing to start off with to get the engine more responsive, and with a little more torque at low revs ?
I have been looking at cams, TB, headers etc etc , and would greatly appreciate your opinion on the best 'path' to go down. Imagine you have $1500 to spend over 7 months.. what would you do?
Chip ? Cams ? TB ? Speakers ? New knob on the gear shift ? :-)
Thanks for the time anyone spend responding
03-25-2003, 06:46 AM
<center><img src="http://pictureposter.audiworld.com/25140/dsc00094.jpg"></center><p>In greater detail, (1) ask Lloyd for a custom TDL Throttle body--he can make anything you ask (see above) (or wait until URS4 gets his operation together); (2) TDL ported Intake Manifold; (3) Short shifter (your preference UUC, Neuspeed, Stratmosphere, etc.); (4) UUC Rob Knob II (heavy shift knobs now in stainless steel and carbon fiber covered aluminum); (5) Coilovers (again suit to your comfort level, adjustability desires, and price range); and (6) a Neuspeed 19mm rear sway bar (to neutralize the handling--after you get the coilovers!!!).
That should keep you close to your budget, as long as you get things on sale. My tab for all of the above parts remained at or below $2000 for the parts (installation extra).
I will let everyone know how ported heads and unequal length headers affect power in the coming months. :-) I will also install an EFK, but everybody already knows that it frees-up an extra 10hp.
Hokie - STI avant
03-25-2003, 09:27 AM
Just adding a ported intake manifold and a TB on a stock engine will not yield much of a hp gain. You would need to get an exhaust, and P&P the heads as well.
03-25-2003, 10:38 AM
if you didn't live so far away I'd give you a ride.
I know it makes a big difference, because I first installed a TBody with a sleeve port only; I then installed the ported Intake Manifold; I next added a ram-air extension to the air inlet; and, finally, I installed the TBody with the reshaped inlets and polish job. Each step of the way, I saw power gains, because changing the dynamics of the air flow changes the amount of air that gets into the combustion chamber at a given percentage of throttle.
Now, I have no doubt that I cannot realize the full potential of the increased air flow until I open up the heads and add headers, but this in no way limits the increased air flow you can achieve before it gets into the heads.
For normally aspirated engines there exists one rule: breathability begins at the air inlet and ends at the tail pipe.
Even when you have a restriction, increasing the air flow before the restriction still increases the air flow through the restriction until you reach 100% of the restriction's flow rate. That's why you need to look at the power curves more than the highest values on those curves.
For example, the ported intake manifold makes a big difference, because, when ported, the lower, longer runners that power the car until 4000 RPM allow a lot more air into the combustion chamber prior to the switch over to the shorter upper runners. This unquestionably increases your power output at lower RPM's and allows the car to achieve more power at high RPM's, because the engine has less inertia to overcome.
Every Audi mechanic who has driven my car immediately noticed the increased power curves and complemented me on how greatly I improved all-around performance with just the mods I had on the car. Additionally, every one of those Audi mechanics believed that my 12v had more power than a 30v.
Hokie - STI avant
03-25-2003, 11:00 AM
I was just going on what I have read/gathered from reading the 90 forum.
If I got the TDL ported intake manifold... how much difference do you think I would notice? I have a ported TB and exhaust on my car.
03-25-2003, 03:55 PM
If you look at my TB: you can see three types of work done on it. First, you can see the sleeve port (that which most shops--TAP, BlauSport, ECS--do for about $300). Next you can see the reshaped intakes (this TDL does--in addition to a milling port of the primary intake valve--to smooth the air flow on its $200 port job). Finally, you see the polish (which I did myself and takes a few hours of numbing hand and machine labor). Depending on how much you have done, you should generally get greater air flow.
On the intake manifold, you will see the greatest increase due to the 18% volume increase in each of the six lower runners. By porting the TB to the max, you can fully utilize the increased volume of the ported intake manifold.
For example, over the year that I did my mods, on several occasions, the mods tripped a CEL with DTC codes indicating lean condition on both engine banks. This means that after the mod, the engine had more air and that the ECU had not yet self-adjusted to increase the fuel to meet the ideal 14.7:1 air:fuel ratio. This happened with both TB mods and the intake manifold mod.
Depending on the mods you have made on your OEM air inlet and air box (as this is one of the only differences between the 90 12v and A4 12v), you should see a big difference; I custom fabricated from sheet aluminum a ram-air style attachment to my air inlet to force the air up into the inlet on top of the radiator and through the twisting and convoluted air passage to the airbox over two feet away. This makes a lot more air readily available in the air box for the engine to draw at higher speeds.
Unfortunately, I have not yet dyno'ed the car, so you will have to rely on the proverbial "butt dyno" results. However, as I indicated, every Audi mechanic that has driven my car believed that it had more power than an A4 30v. Thus, I estimate the car is making at least 190 but less than 200hp, and this stands inline with the estimates that various tuners have given for the individual mods similar to what I have as well as the expected hp increase of future mods I will get (based on TDL's dyno results on a 12v with the 230hp conversion mods--some of my mods flow equally, some greater, some less, but basically very close in overall breathability improvement).
Interestingly, I hear an easily perceivable air flow increase in the engine sound at WOT.
As for throttle response, you will feel a huge difference at your foot, as the increased flow dramatically improves the throttle "resolution" (as UrS4 defines it) giving you more response and control and an over-all more precise feel.
Thus, even if you only have half of the aural or vector sensitivity that I have for my car, you should still sense a big difference.
03-25-2003, 07:58 PM
I'm working on a supercharger setup. That's how I'm getting over the slow factor.