Thanksxxx,

As i mentioned before, the ECU really pulled everything together for me. Mind you, I have extensive head port work, Fabspeed intake, Underdrive pulley, exhaust and big wires.

The ECU smoothed out the throttle response and gave me more usable power under 4k rpm. The car pulls like a freight train to redline and never falls off like before.

The best way i can explain the feel is if you have owned an old carburated muscle car. if the plugs and filter havent been changed in a while..it was usually time for some work. Imagine fresh filter hotter plugs with 4-8 degrees of advanced timing put in. This is what it reminded me of!

I love it!


Oh and for power.... 345 to the wheels. 3.4 ltr.

 

345 rwhp on what dyno and what gear?

What kind of headwork and any cams?

 

The Dynojet model 248 was used. You ask about the gear.....are you talking about the dyno gear resistance? or the final gear ratio in the car?

I'm not familiar with the dyno specs, but my car is a 99 with the LSD option.

The big job in the head was porting. the guy spent a total of 20 hours on them...( thats what he said and what i paid for) but i trust the guy. He said that that there was plenty to trim and talked me into adding 1mm larger valves. I dont know anything about those but it took him 2 weeks of research to find what would work. i remember him saying something about the length being the same as an audi engine.. i cant remember. All i know is that im VERY familiar with head porting and you can get BIG POWER from spending time on them.

No cams for me here. The car is fast. It runs very high 12s/consinsent 13.00s @114 depending on traction and i am very happy with the outcome.

Just yesterday i had some fun with a stock MK2 and from a 60mph roll to the end of 3rd gear i had about 10 cars on him... its fast.! Screw the turbo kits... its fast enough for me.... AT LEAST FOR NOW!

 

Thanks for the explanation. Would you say most of your gains were from the head porting then? It sounds like the factory heads are not as efficient as they can be?

Did you mill the heads any for added compression at all?

 

Yep.. all the power was in the heads. and i did get about 1/2 point on the mill. Im sure the intake and exhaust help out, but on a stock engine??? Eh.. probably not so much.

The ECU tune was GREAT! it really tied everything together.

 

Were the dyno number you posted after all the mods were done?

Do you have any numbers prior to other modifications like the ecu tune or headwork by chance?

 

yes.. the numbers were done after the mods. I had an IMS failure along with a broken cam chain and a smashed oil pump gear, so i didnt have the chance to get a before run. All of the mods were done as a spur of the moment kinda thing. You know... "while im in there" sorta thing.

I hear stock dyno pulls scattered anywhere from 260hp to 288hp...

 

i was always told the stock headers are as good as it gets for the 996tt, i would have thought this would also be the case for the n/a 996, but maybe not

has anyone done headers that have been dyno proven to work ?

 

Some have reported gains with the x51 headers along with some other mods.

Surprisingly, the x51 Headers actually made more hp than some of the cheaper no name brand aftermarket equal length headers.

I would like to see a head to head comparison on the dyno between x51 headers and brand name aftermarket headers like Fabspeed, FVD, Agency and such...

I'd be curious to see if the equal length ones using a true merge collector along with the proper sized primaries and proper port matched openings free of any defective metal obstructions in the path would better the x51's.

 

Buzz...

We are talkin about heads here... not headers.

 

dohhh, i was skip reading here and 2 other sites i''m on, and i'm in a business meeting, i guess i should pay more attention lol