Rebuilding my engine this week...
04-27-2014, 06:36 PM
#91
Rennlist Member
I looked into the conversion of the stock cats. The best price I found was Gert in the UK, who charges around $950 + shipping. The prices from 2 different US shops were significantly higher, to the point where it is cheaper to buy a set of sport cats. I found a set of Dansk Dual Flow Cats for a good price , but if that hadn't of happened I would have sent the cats to Gert.
04-27-2014, 06:47 PM
#92
Rennlist Member
Thread Starter
I didn't have the work done myself. Another Rennlister did, and I simply don't know what he paid for the work.
06-23-2014, 03:00 PM
#97
Rennlist Member
Thread Starter
I haven't had it on the dyno yet. It's fast. Really fast. A truly great engine -- no change in drivability, and it starts, idles, etc just like stock. The idle sound is a little different though -- a bit choppier. The lower end of the RPM range feels similar to before, and then you feel more torque in the mid-range, and then it comes on cam around 3500 RPM's and really takes off. It's not like the stock motor, which feels like it run out of breath near redline. The 9M motor wants to blast through the redline. Where you notice the power the most is in the higher gears -- 3rd through 5th -- where it feels like you've got it in a lower gear.
One reason I'm not in a huge hurry to get it on a dyno is I don't think the raw numbers will mean very much. I checked the AFR's with an LM-1 so I don't have to worry about that. I'm pretty sure this is a 350 hp motor, but I didn't dyno it stock so there's not much to be gained dynoing it now. I'll do it one of these days.
One reason I'm not in a huge hurry to get it on a dyno is I don't think the raw numbers will mean very much. I checked the AFR's with an LM-1 so I don't have to worry about that. I'm pretty sure this is a 350 hp motor, but I didn't dyno it stock so there's not much to be gained dynoing it now. I'll do it one of these days.
06-23-2014, 04:22 PM
#98
For the amount of money you spent to build the engine you would do well to spend a little more ($100 for 3 pulls with full data file) and use a dyno to tune it. By comparison to a Dyna Pack wheel dyno a LM-1 is a homeowner tool.
You could be leaving something on the table or worse, be running in a lean condition and not know it.
Mike
You could be leaving something on the table or worse, be running in a lean condition and not know it.
Mike
06-23-2014, 06:04 PM
#99
Rennlist Member
Thread Starter
http://www.innovatemotorsports.com/products/lm2.php
Problem is, there are very, very few people in the U.S. who can livemap the ECU in a 993 (I have the .376 unit from a 1997 model, the kind that can be flashed).
Anyone know if tuning by mail is a reliable way to proceed? There just isn't anyone within hundreds of miles of me (mid-Atlantic) who can livemap my ECU.
06-23-2014, 06:27 PM
#100
Rennlist Member
Thread Starter
The AFR's, BTW, run as follows:
13:1 up to 4500 RPM. Then they come down to about 12.5:1 and, as redline is approached, they creep up a bit toward 13:1 but stay in the high 12.XX:1 range. Pretty hard to improve on that, I think.
13:1 up to 4500 RPM. Then they come down to about 12.5:1 and, as redline is approached, they creep up a bit toward 13:1 but stay in the high 12.XX:1 range. Pretty hard to improve on that, I think.
06-23-2014, 06:34 PM
#101
Rennlist Member
I'd call Steve Weiner on your question. For 993 tuning, I'd consider him the go to guy with a lot of experience in what does/doesn't work.
On my '84, I used Steve Wong for tuning, and he was able to dial in a better tune with my dyno data. Certainly not the same as a live tune, but it helped.
On my '84, I used Steve Wong for tuning, and he was able to dial in a better tune with my dyno data. Certainly not the same as a live tune, but it helped.
06-23-2014, 06:51 PM
#102
Burning Brakes
Join Date: Aug 2012
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I did the labor myself, so not too bad. The 9M heads/cams package is a bit north of $10K. The pistons and cylinders were $5K. The mechanical rockers were $400, plus $400 to have them reground and rebushed. Knock off a couple thousand from that for all the take-off stuff I can sell, and the price above a stock rebuild is about $14K. If you really want to justify it further you can knock off the money you don't have to spend getting your stock heads redone. I wanted more power and would have had to spend significantly more than that to sell my car and get a 997S, but I wanted to keep the 993 anyway. For me it was worth it.
06-23-2014, 09:20 PM
#103
After my 95 C2 engine build with head work and cams, I got a chip from Steve Wong programmed to his experience with my build details. I did a dyno run and used the data file to have Steve optimize the fuel mapping on his chip. When I dyno'd after the chip change I picked up 11 HP, same dyno, same weather.
The issue is not the O2 sensing it is the dyno's ability to control the engine loading for repeatable runs. The LM-1 is a good sensor but would you reprogram your AFR based on it's readings?
The issue is not the O2 sensing it is the dyno's ability to control the engine loading for repeatable runs. The LM-1 is a good sensor but would you reprogram your AFR based on it's readings?
06-24-2014, 12:03 AM
#104
NP993 - all that is left is a short-ratio gearbox 
What I love the most about your build, however, is how quickly you got it done. A-freaking-maze-ing is what I describe how you knocked that project out so quickly (my rebuild had a first post of 2/22 and it was only running again on 6/19!!)
Nice work and a great result from it!
What I love the most about your build, however, is how quickly you got it done. A-freaking-maze-ing is what I describe how you knocked that project out so quickly (my rebuild had a first post of 2/22 and it was only running again on 6/19!!)
Nice work and a great result from it!
06-24-2014, 12:56 AM
#105
Rennlist Member
NP993 - all that is left is a short-ratio gearbox
What I love the most about your build, however, is how quickly you got it done. A-freaking-maze-ing is what I describe how you knocked that project out so quickly (my rebuild had a first post of 2/22 and it was only running again on 6/19!!)
Nice work and a great result from it!
What I love the most about your build, however, is how quickly you got it done. A-freaking-maze-ing is what I describe how you knocked that project out so quickly (my rebuild had a first post of 2/22 and it was only running again on 6/19!!)
Nice work and a great result from it!
