lucky_evo

iTrader: (3)

I'm always up to some good conversation.. sounds like a plan

ssteve

iTrader: (5)

Very true. Maybe you could do the mani & hotside after a full tbe then since the stock dp will also effect things

9sec9

iTrader: (2)

My thoughts on the exhaust: By removing the most restrictive item first, then progressively the next, and the next, we'll find the least number of items required to achieve the 11.50 goal. The cat may be first, then the ported O2 or SS replacement. A ported O2 CAN be done by the individual for the cost of a stone or carbide cutter, but not everyone has the knowledge nor maybe the grinder. The first motorcycle head I ever ported was done using a regular drill and stone, but that was aluminum and nearly 40 years ago. I think I still have my ported O2 housing, so that is an option too. It might be best to use a test pipe AND ported O2 first.

Indy Evo

iTrader: (41)

I've looked in the for sale threads for injectors, they average about 240-260.00 dollars. We have sourced what we need here in town for 100.00, but I will use the for sale threads to base actual available cost. I also found a test pipe on AMS's website for 50.00 for their system, but it gives a good idea on the cost. So on the high side of things using the prices in the for sale thread, and the new test pipe from AMS one would have no more than 431.99 plus shipping in parts total, or less depending how far one goes. Best of all still under 500.00 total for this project.

Another option would be just a 100 cell cat from Mil.Spec which would bring our total to 350.00 with three mods and 150.00 under budget.

P.S. I forgot I bought a SS o2 housing used for 40.00 so we have that option, and someone left a prototype FP White (the one they said did not work on this forum) here the last time they came by. It can be dropped in the stock hotside since at some point in their life the stock turbo will need to be rebuilt. Plenty of options to choose from and plenty of myths to bust.

9sec9

iTrader: (2)

Indy and I are on the phone talking and we both are thinking of the NEXT mod might be trying racefuel. With 105-109 unleaded, we wouldn't need to change injectors and no parts would be needed. Also, it's something that anyone could add, swap the tune from the street tune, and race. Then, go back to the pump gas and reflash it to street tune. NO MORE PARTS. We both really like to leave the cat as long as possible. Just another idea.

9sec9

iTrader: (2)

I think it might be good to post some of the lakeside/trackside conversations that Indy and I had this weekend. First of all, we expected the car to easily roll into the 11's due to several improvements we made during the week. First, logging the car during test runs showed us some interesting facts concerning Indy's shifting and the improved results. Second, tuning the car a little differently yielded a higher average 2 byte load than before. I measured the improvements in the 5500-7600 rpm range. At the same time, the average boost was actually a little lower, but not by much. On tuesday night, Indy thought the clutch was out, and now we think that it very well may have been showing us the early signs of giving up.

We absolutely know that the engine is making more power than Tuesday night when it ran the 12.01@113.35. Since then, its gone 12.02, but the mph has slowly been slipping back. Also, the logs have been showing lower and lower boost in 3rd and 4th gears. I think this was due to the clutch slipping and the loads (boost) not reaching the target psi. Another thing I noticed in the 'test/tuning runs' during the week was at our normal peak boost of 5900 in 4th, the boost seemed to fall off a bit, then pick back up. This could also have been the clutch slipping and not allowing the car to accellerate like it should. Although the times have been very consistent on the launches, the tires were spinning, instead of the clutch slipping. When the engine hit full load, the clutch began to slip. If our 'supposins' are correct, we'll see an instant increase in mph and lower et's when the clutch is installed. A stock clutch has the potential to go mid 11's, but not for very long. We had a stock clutch and could have used it, just to see where it's limit was, but for what reason? On Saturday, Indy had flashed the street tune back into the car and went for a drive. Just a roll-on in 3rd or 4th gear caused the engin to jump up 1500 rpms. The clutch was gone. It happened that quick. From slipping a little to nearly gone in about 4-5 passes.

I just thought I would share the benefits of logging and paying close attention to what was happening. MPH was dropping by 1-2 mph, but at a time when it should have been increasing by 1-3 mph. The logs showed it by means of reading the '2 byte loads' and boost. Since Indy logs every single run and tracks it in a spreadsheet, it's easy to retro-analyze the logs and see how it correlates to our changes.

Indy Evo

iTrader: (41)

Sorry Tom, I didn't see your post on the race gas .

9sec9

iTrader: (2)

I'm goin' fishin' a'gin.

vmrevo9

iTrader: (33)

goodluck guys!

Indy Evo

iTrader: (41)

9sec9 is so good he can even tun-a-fish 9sec9's Fish and Chips coming soon! I'll go fishin' and tune, you drive the car ... wait that might not work so well , I'll have to travel more than five miles from home .

Tools of the trade: helmet, laptop, Tactrix cable, wireless card, and 9sec9 on the other end of cyberspace.

Indy Evo

iTrader: (41)

9sec9, what do you think about this instead of the test pipe to keep it green and legal? 2.5" 100 cell cat from Aby and Erik at Mil.Spec. Three engine mods, 350.00 in parts, and zero weight reduction...11.50? time will tell.

Ludikraut

iTrader: (17)

^ I think that's a great idea. When I finally went from a high-flow cat (~ 200-250 cell, IIRC) to a test pipe, I hardly made any extra power. I think the 100 cell cat will be very close in power to a test pipe, will keep the car legal (sortof), and quiet.

l8r)

jid2

iTrader: (62)

Back in 2003 when every part had to be bought new and deals were few and far between I put my exhaust together one part at a time. My first two mods were in fact an air filter and boost control then the downpipe. Then added a test pipe. Then replaced the factory muffler. I did this because I couldn't do $1000+ for a turbo back and keep my wife happy.

But, with all the used parts out there now it its totally different. You can get a full turboback exhaust for $250. I don't know anyone who upgrades their exhaust in piece "format" anymore. Why would you? I don't see people running a stock exhaust with a test pipe; it doesn't make any sense on the upgrade path. If you run a stock exhaust it's because you want it to be quiet and low-key, and 100% legal. Otherwise you just get a full turbo back with testpipe.

Most EVO owners see no barriers to putting a full 3" exhaust on the car right away. So In terms of your guys test data and learning - do what you feel like, do what gives you the data you want. Because everyone else already has a full 3" exhaust on their car...

9sec9

iTrader: (2)

jid2, thanks for the input. When you changed your exhaust, one piece at a time, did you measure or test the improvements in any way? When a 700+ whp car doesn't see much improvement going from 3" to 3.5" exhaust, it makes me wonder how much whp can be gained on a ~400-425 whp going from 2.5" to 3". How much of the gain will be from cat and how much will be from the rest of the turbo-back system. If 75% of the gain can be made in the cat alone, then that's going to be good enough to reach our goal. We both know how to make more horsepower, but the trick for us is to do it while having fun and sharing what we learn as we go. Since Indy's car is certainly still one of the Evo's out there that has a stock exhaust, I'm fairly certain that others exist too.

Ludikraut, your information is very helpful. That gives us a good idea of the next step in our quest to 11.50. I think several other readers would like to see it stay street legal, so that's probably going to be our direction. Thanks again.

jid2

iTrader: (62)

Back when I did it there was no data logging available. All I did was make pulls with buddies and compare to their dyno known numbers.

When I did the downpipe and test-pipe and left the factory mid-pipe it seemed to make the car more prone to boost spikes. It didn't hold a flat boost profile as well. I felt like the parts were helping spool in the mid-range, but still limiting top end. But around the 350 whp level I seemed to be even with cars that were running a full 3" exhaust and I still had my stock resonated mid-pipe in place.

You may know this or not but Dave Bushcur tested every part in the exhaust system around 2004. It's in one of his old threads. I believe he made the more logical approach and started at the cat-back and worked forward, at least at first. Although I do recall he ran a 3" downpipe and stock mid-pipe with muffler delete at some point.