Tuning new set-up in, please advise

[84BuickGNYorkPA]

My signature is up to date. Would like some advise from my Buick family.
Car warmed up after a drive, in park, idle. Fuel Pressure 42 (line off)
O2 753-757 three minutes later number = 687
AF 05
L8 31-32
Bat 13.6
INT 128
BL 145
CLE 167
ATS 113-114
r 875
tps .46
IAC 0
cc 161
NAL 00
Just a note I took the above readings 6hrs ago, went out to check my FP and now the o2 at idle is 398-432. Engine is warm but was a fresh start up not driven anywhere if that means anything, also just reset that idle control a couple of weeks ago, will dig out the instructions and do that this weekend....thanks in advance. Chuck

 

[Blazer406]

One of the first things that I see is the IAC is "0". You need to find the IAC reset procedure over at GNTTYPE and set the IAC between 20-30. You will most likely have to re-set the TPS to the proper voltages. I would assume your car idles high? It is possible it has a vacuum leak.... might ought to start there... and if all appear well..... reset the IAC....

 

[BRAD_PADGETT]

Blazer is correct. Try this first and check the BLM. Once the IAC is in range you want a BLM within 5 plus or minus 128. If you are not in th BLM range there is either a vacuum leak or exhaust leak. Keep posting numbers and you will get advice. Brad

 

[84BuickGNYorkPA]

Update

Found a vaccuum line in behind the dash hooked up to nothing (it might be for the heat/A/C climate controller). I pluged it and then put a zip tie on every vaccuum hose connection that I could find. These are numbers from tonight after a drive, car in park idling.
O2 785
AF 05
L8 35
INT 128
BL 129
CLE 179
ATS 127
r 825
tps .46
IAC 11
cc 01
Some observations, I have a slight stumble just off of idle(could it be the higher fuel pressure?), only seems to happen when the car gets above 180 degrees. My radiator looks sub par inside, I have that RMI 25 in it for about a month, but the radiator that came with engine swap might need rebuilt (lots of buildup in the passages inside). A local radiator shop did another guys GN and he was very happy with the results. The other thing that I need to do is get the cold air kit, either make it or buy one(I read this helps the off idle stumble). If I still have a heat issue, I will need the Ram duel fan set-up. The fuel pressure line off is now set at 45 lbs. and the boost is set for 20 lbs. It only gets knock if I get crazy wheel spin in first gear(that's as in one wheel), I need a posi.... bad. Second gear wheel spin is fine, no knock(35-40mph then punch it down). The car is running strong(I was a hot air guy since June 79(Buick Sport Coupe). The reason I have the fuel pressure up to 45 is because it was showing at 20lbs boost, O2 of 719-735, with a 1.4 KR. On one run I did turn the boost up to 22-23 lbs(after bringing the fuel pressure up) during the run with .4 KR, I quickly turned the boost back down to 20lbs. Any suggestions for tunning from here? Maximum boost? Fuel pressure? Thanks for the suggestions, comments and help. Chuck

 

[Quick6]

Chuck,
The radiator shop that did the core exchange was CR. Smith in York. 717-792-4709. They installed a 3 row core hi-eff that has worked very well. I removed the rad and re-installed. They did the core and pressure checked. Total cost was around $180 I believe, this was about 2 years ago. With the new core and the stock fan my temp goes between 160 and 170 city or highway.

 

[84BuickGNYorkPA]

Thanks Bob

 

[Blazer406]

IAC is still kinda low..... I would do the IAC/TPS reset procedure like on GNTTYPE and report back.... idle IAC's on a warmed up engine should be around 30 or so..... the fact that they are 11 ..... indicates the engine is trying to lower the idle.... if you adjust the throttle stop screw a half a turn or so.... the IAC's should come up...... and stabilize some.....

 

[Blazer406]

...... just saw Eric's recommendation on the turbo tweak site...... shoot for the 20's on the IAC..... not to exceed 30......

 

[441120]

Looks good!
Are you running 20 psi with alky and 93 octane?
You should be able to run that boost on 93 alone.
You have more left in it, slowly increase boost and watch those O2 and KR numbers.
Oh yeah, start shopping for a posi :biggrin:

 

[84BuickGNYorkPA]

Ok, I have to fix a computer tomorrow evening and I'm taking the Buick. When I get home, I'll check all the readings again and if the IAC is still low, I'll reset it.(gotta dig around for that thread) This comment about not needing Alky at 20 lbs boost has come to me before, but the chip that I had Eric @ turbotweak burn for me was a chip that does require alky. I had thought about getting a non-alky chip ... briefly, but then decided that's money that I should put towards the posi. Which is a area that I know nothing about, apparently I can get the posi unit and put it in the exsisting rear? I hate to think about the parking brake lines, plus all the hassle and cost of changing the whole rear end assemble from brake drum to brake drum.
Thanks again for all the feed back, I would not know which way to turn without all of your comments/suggestions.

 

[441120]

You're right, the chip maker knows best about what he programed.
The carrier in your rear is what needs to be changed/serviced. The whole rear axle does not have to come out, the cover comes off and axle shafts come out. Then the carrier with the ring gear comes out and if not originally a posi then a new carrier(posi) is installed with new bearings and reuse the ring gear(ring and pinion are a matched set). If originally a posi it can be rebuilt in the car.

 

[84BuickGNYorkPA]

Thanks, that really doesn't sound that hard to do. Lift the car with the floor jack, take the wheels off, pull the cover. Carefully disassemble the rear/ pull the axel's part way out, install the posi unit, reassemble. Since I am a machinist, I have what ever indicators and feeler gauges I might need to set it up. I would just need to do a search on the subject for clear instructions.

 

[441120]

You'll need a press for the carrier bearings, and get an assortment of shims to set up the backlash between the ring and pinion, and set carrier bearing preload. Keep the original shims and bearing caps on the sides they came off, don't mix them up. When reinstalling try the original shims as a starting point if they fit.
Ring gear bolts are left hand thread, use lock-tite.
When checking backlash check in four spots around the ring gear for run out. Look for ~ 0.006" +/-0.002" even at all four spots, I use the cross shaft as starting point then go 90* so I check the same four points. If excessive runout try reclocking the gear on the carrier 180* depending on runout readings. If you get the backlash set correct,. the gear pattern should be good because you didn't change the pinion depth.
Now would be a good time for a T/A cover, maybe Moser axles :biggrin: