the consesus everyone here and Fred at Evo have stated is that my dyno is way off....Fred at evo stated no way am i only getting 258 with my mods....he said the guy had to be dyno testing wrong....not locking out 4th.....I will go and get retested somewhere else.....I will look for another Tampa dyno area...does anyone reccommend or heard anything about revextreme or coastal dyno.....I spoke with Fred at evo in length....and not to defend Fred yet again...but this guy calls me back and emails instantly all the time....he also claimed that the numbers he was pulling from my cat are inaccurate as well...or whereever it is the O2 sensors are in at....he said that it will always read lean as the cat is getting rid of the excess fuel...he stated that my car is probably running too rich now...he stated the only way to pull accurate numbers is directly from the headers before the cats..anyhow....I am going to get another run...and if another place shows me the same numbers then so be it....it still feels fast as shiznit and sounds awesome....thanks for everyones input and guidance

[IMG]local://upfiles/42783/6AEDB89FF96C44DFA6B05F5F80DBD38A.jpg[/IMG]

 

i know a good place in jax fl, i can get you discout to , it a 4 hrdrive i believe, but it might beworth it

 

Like I said, VMP is probably the best in central FL. How many threads are you going to start on this subject anyway? lol

 

I'm glad Fred is getting back to you.

So are you welding in a bung in the header, is that what Fred says you have to do for his tune to be measured correctly?

 

Coastal is used by alot of the Tampa guys. Some of them are running 8 second fox bodies...

 

yes, that is the only way he said you can get a true A/F reading, unless of course I had no cats....then I could have got it from the x pipe O/R..since I have the cats...out of luck

 

yeah, but i am concerned he has little experience with s197...

 

Cheftjpeck,

I am really interested in how this turns out. Are you planning on welding in the bung in the header? I recently had a very lean tune from Fred at Evo with an A/F mearsurements of 14.2-14.8 read by a tailpipe sniffer at on shop. I went to another shop and they measured the A/F from where the factory O2 sensor is located which I beleive is in or immediately after the cat. Those readings were 14.0-14.4. I had the dyno shop tune my car with an A/F of 12.3-12.6 measured from the factory O2 bung in the cat.

Many people on these forums and others have said that it is true that getting an A/F rading as close to the engine is the most accurate so a reading from the header would be best. However, while some people say that their A/F was X at the tailpipe and Y at the cat and Z at the header, they all have said that the difference from the tailpipe to the header 0.5-0.8 leaner at the tailpipe. One guy did say that there was a difference of 1.0.

I needed a 1.5 to 2.0 reduction in A/F measured at the cat and a 2.0 to 2.3 reduction measured at the tailpipe, which is way more than what others have said the cats and the rest of the exhaust system can change the A/F. Granted, I did not poll everyone who has had their A/F checked in all three locations, so I'm not saying a 2.0+ change in A/F can't happen in our exhaust systems or maybe in just mine.

If you do weld in the bung and Fred's tune has the correct A/F, which I sincerely hope you do for all of us wondering about the complexity of an accurate A/F. I hope you get on here and tell us the results, there have been a lot of bashing going on and this would be very good information. If the A/F measured at the header with Fred's tune is right on the money then at least I will know that I may have gotten a dyno tune in vain and that since my car was tuned for a 12.4 A/F at the cat, I am probably running really rich.

 

VMP is really not all that far, but you know his price to tune on the rollers is a little $$
You might try calling him and see what he would charge for a basic tune for your mods and if you pay just to have 2 pulls on the dyno if he will adjust it if the A/F is off..
Might be able to then get his great tune and be sure your A/F is on the money with out going for a full blown custom tune