Originally posted by Fierobsessed: the other runs into the C500 (D3) which was the temperature light. From there it makes it to the cluster, where it will be locally wired to the sunbird boost/tach.
Why on earth are you doing that?
Edit: Nevermind, I was thinking MAF rather than MAP
[This message has been edited by Will (edited 10-12-2013).]
Fierobsessed
OCT 18, 09:41 PM
Just a little bit of spooling and a bit of boost...
I finished the intercooler plumbing this morning, wired the pump to key on power, and filled the system with coolant and bled the air out. Seems to be working well. I may also need a lighter spring than the 11 psi spring in the blow off valve, I'm getting a bit of off throttle turbo surging sound. I've been playing with the tune and sorting out a few misc issues I've had. I've been so busy that I really haven't had the time to do many updates. But it's all turning out well!
Fierobsessed
OCT 31, 11:08 PM
I've been keeping busy on this project. I had to sort a couple of leaks I had to sort out, namely the turbo water fittings again. I wound up using AN $$ fittings to replace one of my custom pipes. Once that was taken care of, I did some basic tuning and drove it around a bunch. It drives great in open loop, terrible In closed loop. I have my work cut out for me tuning wise.
I've spent the last two weeks doing a complete hack on $6D, which is pretty much 96% identical to $8F. The only differences: Calculation of map variables (due to map sensor difference) 6D has shift light logic 8F has wastegate code.
They basically took $6D and cut the shift light logic from it since 8F was an "auto only" and reused some of the ram slots for the added in wastegate code.
After doing the hack, I polled the differences between an otherwise identical $6D manual ATWX and an automatic ARYH code, and applied whichever differences I felt were applicable to my 8F code as a tuner pro v5 patch.
Then, I copied the section of code for the shift light from 6D to an open area in 8F, patched in the logic option to turn on or off the shift light code, (it was always there for some reason) added the appropriate jumps, corrected the internal addresses, and assigned new ram slots to handle the shift light timers involved. All this to make 8F have a fully functional manual option. I also had to re-disassemble 8F to make sure I didn't make any mistakes when adding in the new code.
It is extremely time consuming doing a full hack. But with 8F being well hacked, it was a matter of lining them up next to each other. And move the descriptions over.
In the meantime, I tore the front end apart. I had installed poly bushings 5 years ago, and I had the upper control arm bushings seize to the shaft, and the shells broke free of the upper arms. It was a bad situation. I'm replacing the front bushings with rubber, and putting in Rodney Dickmans tapered front bearings and zero lash end links. Hopefully this will all make the front end as good as the day it was made.
I've come to the conclusion that poly sucks for some things, and is excellent for others. My lower control arms in the front worked excellent with poly, but I had numerous problems with it on the uppers. The rear toe and lateral links had problems, but the trailing link was perfect. At the end of the day, the larger, and less rotated poly bushings were fine. It was the little ones that had all the issues. I was considering using poly in the lower control arms, but I decided I didn't want the maintenance of poly at all.
So I'm still busy, and since the heavy code work is done, I can get back into tuning as soon as I get the front end back together.
BV MotorSports
NOV 06, 10:22 PM
Hands down one of the finest engineering examples on PFF. You got to love that first drive, eh?
Fierobsessed
NOV 08, 12:18 AM
Thanks! I've taken quite a lot of pride in the work that I have put into this. It's the best work I've done I think.
It's quite powerful but it needs so much tune work, and I'm still sorting out stuff. Like surprise leaks.
Here's one that wasn't a surprise, but rather a disappointment.
So... the axle seal is leaking a little. For now I'm going to just pretend everything is fine
I thought a bit about spark plug selection. I've had Autolite Iridium XP5243's in this engine forever, I really like these plugs. But realizing that they are old, and still gapped to 0.060". I got a cheap set of NGK TR6 plugs and decided to put those in. 0.040" gap. But being a 3.4 DOHC Fiero, this isn't the easiest task, but quite a bit worse than the old 2.8's.
These three are perhaps the easiest to change in all of automotive history, provided you have a long enough extension.
But... once you remove the decklid, you're confronted with this catastrophe.
No problem, I'll just put the jack under the back of the cradle, unbolt the dogbone, remove the bottom two rivets from the two splash guards, remove the rear cradle bolts and lower the engine... Now, I can just squeak the wires out, and the socket and extension in and change the plugs.
It probably took about 30 minutes to change all 6 and bolt the cradle and dog bone back in place, and put the deck lid back on.
Driving around, I didn't notice much of a difference. But at least it's something I don't have to worry about now.
I'm still playing around with tuning. It needs a ton of work. I have done some testing, and It's clear that I have a few things to sort out. The engine hits a solid wall while boosting and I'm having trouble identifying what that wall is. But I'm afraid it might be turbo surge? It makes the characteristic sound of it. Maybe the air filter is too small and restrictive??? Either way, it's something to test.
sleevePAPA
NOV 08, 04:05 AM
boosted with a .060" gap? should be around .025", d/r if I read that wrong. If there is compressor surge you will hear a distinct fluttering that gets progressively louder as the rpm's climb.
As for the wall, spark timing and AFR's, where are they at when you hit the wall?
Hudini
NOV 08, 08:13 AM
$8F has a backwards rev limiter table. For some weird reason the higher you set it the lower the limiter kicks in. If your hack copies $8F you might have the same issue.
tesmith66
NOV 08, 08:17 AM
I dropped my DOHC down until the bottom of the pan was level with the lowest part of the cradle for the most upper clearance possible.
I can get the boots off of the front 3 by pushing them forward, then pulling them at an angle towards the passenger side. I pull the plugs by dropping the socket into the hole, then the extension and then attach the ratchet. Unscrew the plug all the way, disconnect the ratchet, pull the extension until I can reach the socket and disconnect it, then use a magnetic pick up tool to get the socket and plug out. I pulled the rubber thingy out of the socket so the plug will stay in the hole- that way if the socket drops off of the magnet it wont smash the plug gap. I start new plugs with a piece of rubber hose (don't forget the anti-seize!).
Learned this method when we had a Ford Probe with the DOHC V6.
Do you have some sort of water diverter or rain guard to keep the front 3 dry? I have already had trouble with water getting in the plug wells and causing weak or no spark. Had the same problem with the Probe if I got too crazy at the car wash.
------------------ 1986 SE Aero coupe.
3.4 DOHC swap is complete and running, now just have to finish the rest of the car...
RobertISaar
NOV 08, 09:46 AM
quote
Originally posted by Hudini:
$8F has a backwards rev limiter table. For some weird reason the higher you set it the lower the limiter kicks in. If your hack copies $8F you might have the same issue.
most, if not all of the MPFI 60V6 masks are actually like this. however, most of the XDFs have the correct conversion in them. for some reason, the 8F XDF was released with a LOT of conversion errors in it.
also, .060 on a LQ1? i want to say factory gap was .045? any benefit to running it .015 larger than normal? i know the theoretical benefits, but i wasn't sure if even a stock engine was going to deal with spark blowout.
Fierobsessed
NOV 08, 03:20 PM
"They" don't tell you this, but you can get away with a larger gap if your gap has pointier tips, like the iridiums do. (think Tig torch, or lightning rods, pointy for that reason) And you get a healthy spark out of DIS anyway. I never had any issues with spark with the .060" N/A. Heck, I deliberately spread those plugs to that gap because I knew I could get away with it, N/A of course. But being boosted, I figured it might be the source of trouble. Still, it was not. Surprisingly.
AFR's were floating around 11.5, and timing was 8-10 degrees (weak!) and 8 lbs. Which was coincidentally registering a light knock. Unless my intercooler is garbage, or something else is wrong, shouldn't be knocking with those conservative numbers. That's why I was thinking plugs. If your fuel and timing is right and your engine is hitting the wall, and your turbo is fluttering... its probably mechanical. It could be caused by: Compressor surge itself, which would likely be the intake filter restricting the air enough to raise the pressure differential across the compressor past the surge line.
A loss of spark, which should cause compressor surge as the turbines driving force is being removed while still under boost at WOT.
An exhaust restriction, which again will cause compressor surge due to a decrease in turbine drive, like a broken catalyst.
I'm going to try removing the air filter just to see if that is what the trouble is. It seems likely, especially if the turbo happens to be running anywhere near margin.
Hudini, you are absolutely correct, the program loads reference period, which is inverted to RPM then compares it to the cutoff value. So if you raise the value, it does in fact lower the rev limiter. But, the 8F definition did have the correct formula (1310732.000000 / X) for the value. So, it shouldn't have the inversion issue. I haven't touched that value anyway, I see no need to rev it that high... yet
Tesmith, I couldn't really lower this engine's mounting due to the fact that the F40 transmission is naturally a bit downward leaning at the differential. its axle cup would scrape the frame if it were lowered by any real amount. Also, I am using a stock 88' fiero front engine mount, and that completely dictates height. As well as the transmission hanging lower off of the bottom anyway. So any ambition I had to lower the engine via custom mounts was fraught with complications. So I decided it would just be best to leave it where it was. I still think 1/2 hour was pretty good time to change the plugs, considering that I had to remove the decklid and swing the cradle a couple of inches. I probably won't have to do that again for a while anyway. Or so at least I hope!
