mw66nova

iTrader: (13)

you'll be happy with any m/t product

QwkTrip

iTrader: (22)

Okay, I think I'm going to take you up on this. The idle after cold start needs help. This video is a cold start at 76F tonight. The idle slipped down, surged up and down for a bit, and then died. Once the engine warms up the idle is fine. What tips can you give me for tuning idle after a cold start? Also, after I gave it a rev the engine hung and didn't go down to idle. It did this last time it came home from a tune and went away after a few days. At that time I concluded it was a mechanical problem that worked itself out, but here it is back again.

I was advised that I would need to work on the cold start idle as weather conditions change. I think they said to crack the throttle a bit and if idle improves then the mixture is too rich, or if it wants to die then the mixture is too lean. Sounds like a simple process I can follow.

The cold start idle actually had no trouble at all before the tune (on the old tune). Maybe I should just go back to some of those old cold start enrichment and speed settings?

QwkTrip

iTrader: (22)

I found some helpful info here, about half way down the page (key word search for 'decay'). I think I can figure this out.


http://forums.holley.com/showthread....ist-Holley-EFI

QwkTrip

iTrader: (22)

I'm a newbie at tuning so opinions are welcome.

From what I can tell that was a slow stall caused from a rich fuel condition. In that case I have a choice of changing the fuel enrichment by coolant temp, or changing the A/F ratio by coolant temp. I studied a data log and noticed the closed-loop learning was adding fuel trying to achieve a rich A/F ratio. It seems the A/F compensation for low coolant temp is more than my engine likes so I backed down the A/F compensation (leaner). I didn't touch the fuel enrichment table yet.

I think that makes sense, doesn't it? I guess I'll know tomorrow morning when I try another cold start.

Jaysz28

iTrader: (30)

when I was having cold start issues I would mess with the 'fuel enrichment vs coolant temp' table. I think it was labeled startup, but my brain is a little fuzzy this morning.

First thing. Get a note pad/pen out. Write down all the changes you make with the results you get. I also change the file name, such as coldstart1, coldstart2, etc. You dont want to dig yourself a hole to the point of the car not running.

FYI, tuning cold starts is such a PITA, as you only get one shot at it a day basically, or two if you drive it to work and want to datalog it when you start it before leaving for the day.

my best advice is look at it as a graph or table. Then look for a spot where it is happy and then adjust accordingly. For example, if it starts and runs great when the coolant temp is at least 130*F, then just look at your graph from your cold start temp to 130*. If it is a drastic slope, you may have to raise or lower points around that area.

Also remember, you shouldn't compare open and closed loop idle characteristics. Open loop is just running the motor on set paramaters without using any feedback from the sensors. I have cheated in the past and enabled closed loop fueling in as early as 1 min on a cold start, and 30 secs or less on a hot start.

Another note, you may want to read in the DIY prom forum. They have a lot of smart guys using antiquated hardware to get motors running. There are a few articles on how to tune idle, cold start, etc. All the sensors work the same, just a lot better PCM to run them. I sometimes miss the old days.... lol

Good luck

QwkTrip

iTrader: (22)

I got a much better cold start this morning.

After the engine warmed up I started playing with the injector end angle. That got the idle to improve again. Changing injector end angle has made a tremendous difference of torque off-idle. I can actually let out the clutch with no throttle and the engine will stay alive!

Jaysz28

iTrader: (30)

Awesome! Congrats!

Just make small changes and keep track of what works and what doesn't

It maybe a 'self tuning' ecm, but it can only adjust so far. As with any pcm, the closer the base tune is, the better the car is going to run.

QwkTrip

iTrader: (22)

After the Nitto NT05R tires fell apart, and never had decent traction anyway, I switched over to Mickey Thompson ET Street S/S. Night and day difference! By comparison, the MT tires have so much more traction that it is a joke that Nitto even claims they have a drag radial. I can actually use my power now.

mw66nova

iTrader: (13)

sounds about right.

QwkTrip

iTrader: (22)

My brakes feel better now. I was pretty tired of dinking around with brakes so I just threw everything at it at once hoping for a good outcome.

My goal was to do away with as many adapters as possible. I used a Wilwood adjustable prop valve with inverted flare fittings (no NPT adapters). It also has dual outlets for front brake lines so that eliminated the front line tee, too. Downside is that it is only compatible with 3/16" line so I had to use a couple adapters where 1/4" line used to be. And lastly, I used only Brake Quip fittings everywhere to improve my odds of success.

I threw away my NiCop lines and switched to steel. I found that steel gave me more consistent leak-free results, and it seemed to better tolerate tightening more than once. I also purchased only straight sections of tubing from the local auto store and used the factory flares whenever possible. Previously I had bought long coils of tubing and straightened it myself. I talked to an engineer that works with brake systems and he said his tube straightener has something like 15 rollers. My straightener has only 5 rollers and was causing the tube to slightly square.

The end result..... brake pedal has never felt better, rear brakes work great, and the prop valve actually changes the rear brakes quite a lot.

Update: Still wanting more rear brake. Post #1136 and #1138.
https://www.thirdgen.org/forums/ltx-...ml#post6283966

mw66nova

iTrader: (13)

i have one of those prop valves on our chevelle project. it's not really road worth, but considering i threw that thing together in just a couple months to be able to drive it around whenever it needs to be moved, i am quite impressed that i "got it" on the first try with the brakes, lol.

QwkTrip

iTrader: (22)

The SSBC valve reduced rear line pressure too much and could not be adjusted high enough to operate my rear brakes worth beans.


The Wilwood valve can be adjusted all the way up to 100% (straight through). They don't normally advertise the pressure curve but if you call the tech line you can get a copy sent to you.

QwkTrip

iTrader: (22)

Got to the drag strip for the first time! Unfortunately the alternator failed pretty much the moment I pulled the car off the trailer so the car was running on battery, and that messed with the engine controller and caused the engine to run a little sketchy and die a lot.

I wanted to know what the car does on an everyday basis so I left the tires at 26 psi. My best run was 11.89 with a 1.96 60' time, and my best trap speed was 125 mph. The tires wouldn't hold much of anything off the line but would hold full throttle part way through 1st gear. I'll go back again next spring and work on the 60' time, but I had plenty of fun this round!

I'm contemplating whether or not to pull the heads to get a valve job and to optimize dynamic compression ratio. I know my valves leak because the heads leaked water when I tried to cc the chambers. That could amount to a very significant amount of horsepower loss, or maybe hardly anything. Hard to tell unless I fix it.

QwkTrip

iTrader: (22)

Turns out one of my friends took a video.
The other car is a friend's brand new Mustang GT with the track pack.

mw66nova

iTrader: (13)

car sounds great, and 125 mph is smoking fast for a full weight street car

skinny z

Excellent.

QwkTrip

iTrader: (22)

Did another mod last weekend but not of the usual nuts and bolts type.... Did the "Zaino" mod. The old girl can still turn some heads.

QwkTrip

iTrader: (22)

I am beginning to see signs of cracks developing on the roof at the rear corners of the window openings. No cracks in the paint yet, but definitely some deformation of the paint in those locations. That SUCKS-DIDELY-UCKS because paint and body work is expensive, and it is nearly impossible to repair fatigued metal without annealing the metal again after the repair. Basically you just end up chasing cracks around for the rest of your life.

So, now the race is on to stop progression of damage before it gets any worse. I'm throwing the kitchen sink at it. Suggestions are welcome because I'm not sure exactly what will and won't work. The goal here is to reduce strain in the roof at the corners of the windows.

Existing body strengthening on the car is a Wonder Bar and a set of Kenny Brown subframe connectors that are bridged side-to-side by the front torque arm mount. I thought it was working fantastic because 3 wheels come off the ground when I jack from one location. But apparently it is not enough, or not enough in the right areas anyway. Parts on order right now are,
Important decisions here.... don't want to end up with needing body and paint work.

mw66nova

iTrader: (13)

i think you're headed in the right direction. when i pulled the car down last year i found a bunch of cracks in the floor. this was my solution. between this and the 10 point, my car is incredibly solid now. i believe you may be OK if you did just under car mods.


something else to think about if you convinced yourself to do a roll bar is to do just a 5 point (leave pass bar out entirely) since that's all that's required to 10.00. then make the driver's side door bar removable with those nice clevis type joints. remove the bar entirely with 2 quick pins for the street.

QwkTrip

iTrader: (22)

Strut tower brace Part I -- the Heidts TPI edition

Update: Oops! This did not fit once I tried to close the hood, https://www.thirdgen.org/forums/ltx-...ml#post6111276

Got my strut tower brace. Guys... we all need to start paying more attention to Heidts. It has been a looooong time since we've seen anybody that knew how to do a good 3-point brace like this. I will show pictures on the car after install.

This is the fixed 3-point brace for TPI. Heidts forms the backbone using two bars. The firewall brace is a single bar bent in a U shape and fully welded to the front cross-bar. I did a test fit on my car and the whole unit fits perfect. Tons of clearance over the top of my FAST intake with tall billet fuel rails. Listed at $300 on the website but I'm old fashioned and ordered by phone and got it for $189.




No spindly tab on this unit. There is a huge plate fully welded to the bar, and the plate spans across the lip of the firewall.




No end links or rotating joints either. This is a rigid member of the chassis -- the way it should be. Pads on the strut towers were well thought out. Footprint is narrow and clears my Founders caster plates with ease. No battling for real estate... the stuff just fits like it should.

JayBoCC2

Well ****, i know what i'm buying myself for christmas... the wife is gonna kill me.

FWIW i have hawks T56 xmember and alstons but i have not installed the alstons yet.

Jaysz28

iTrader: (30)

that is a stout strut tower brace!

I've been using BMR's two point for years for many of the same reasons you stated.

I H8 WWD

iTrader: (5)

No TBI Option? Farts! (Edit: Part# CF-426) (Their search function is Prehistoric. DO NOT USE)

Seems like a good piece though. That U-Joint to the firewall, can't believe nobody thought of keeping it tied to the front mount. GOOOO HEIDTS!

Now you know you need to post install pictures/videos/movies/documentaries ASAP ;P ;P

Note: I see they use QA1 branded parts for some of their suspension items. Isn't QA1 sort of disliked on TGO? Might want to stay away from any moving suspension parts from Heidts if they use QA1 "quality" parts. If not then TGO has built a bad rep around QA1 parts over the years. Just don't want to throw Heidts out as a solution before we fully understand more about the details of their items that aren't just pieces of metal welded together.

Sorry if this comes off rude, been having a bad day but rest assure the note is legit sincere and am wanting information.

QwkTrip

iTrader: (22)

Ya, they have a TBI version. Just need to click on the items to see the descriptions because they use the same basic picture for both.

TTOP350

iTrader: (8)

I have put on a few sets of the inner connectors and I don't think they work as well as the outers setups. If you don't have them, you could add a set of outers to help out.
Also, take a look at the pinch weld area under the headliner where it meets up with the vertical B pillar. That could be strengthened by welding in some metal without damaging the paintjob.

QwkTrip

iTrader: (22)

Thanks. I already have a really good set of outer subframe connectors (Kenny Brown). Like I said, I'm just throwing the kitchen sink at it because paint and body are waaaaaay more involved and expensive. I think I'm taking out that flimsy BMR K-member too so that will probably go up for sale this winter.

TTOP350

iTrader: (8)

Perfect on the KBs, have their 3point STB and old southside machine outers on mine, awesome stuff.

ransam

iTrader: (2)

I just bought the wildwood prop valve as I could not get any fluid past the original prop valve. Any chance you could post a pic of how and where you mounted yours?

QwkTrip

iTrader: (22)

I used the same hole I drilled earlier on the original bracket.

https://www.thirdgen.org/forums/ltx-...ml#post5816202

ransam

iTrader: (2)

Thanks that's where I was looking to put it. Are you using 3/16 line for rear going into the distribution valve from the master? I think factory was 1/4 inch.

QwkTrip

iTrader: (22)

Factory was 6 mm for the rear, and 3/16 inch for the front. Yes, in order to make connection to the Wilwood prop valve you have to get it down to 3/16" tube. Everything I did is well documented in post #610.

https://www.thirdgen.org/forums/ltx-...ml#post6083021

If you need the part number of the fitting at the rear axle drop-line just let me know and I'll dig it up. It is a metric thread and bubble fitting.

ransam

iTrader: (2)

Thanks for the info. I've read trough your thread a few times. I was just curious if changing line size would be an issue. I'm assuming that with the prop valve being adjustable the line size isn't as critical. I'm keeping the original master so I have to find the fitting change line size for the rear but I will make new lines for the front.

QwkTrip

iTrader: (22)

Yes, 3/16" line is fine for the rear line on our non-ABS cars. And that is straight from the mouth of a brake systems engineer that I know so no worries about source of info on that.

QwkTrip

iTrader: (22)

Somebody nominated me for Car Of The Month. I don't normally watch that sort of thing but I'm not usually in the running either.

Wander on over there and cast your vote real soon if you get the chance.

https://www.thirdgen.org/forums/auto...tm-voting.html

92BLKL98

Gets my vote, nice ride

obeymybird

iTrader: (4)

Vote added

mwfrels

My vote added. You appear to currently be comfortably in the lead...

M

QwkTrip

iTrader: (22)

Look at this, I actually won!

https://www.thirdgen.org/forums/auto...tm-winner.html

92BLKL98

Hey that's awesome, congratulations for a great ride.

mw66nova

iTrader: (13)

awesome news! congrats

mwfrels

Congrats!...

khulsebus

iTrader: (2)

Congrats, you had my vote

HP52TA

iTrader: (4)

Congrats! Great job on the build, nothing but quality throughout. Well deserved.

grngryoutmyway

iTrader: (1)

Grats man, car looks great.

86FyrBrd

iTrader: (1)

Its nice to see cars from back when I joined and was active, looks killer. You remember my car?

QwkTrip

iTrader: (22)

Yep, the most popular Firebird on TGO.

QwkTrip

iTrader: (22)

Do you still have it?

skinny z

Well done.

QwkTrip

iTrader: (22)

Still in the middle of winter here but got a breather from the cold for one day and was able to tinker on the car. However, it just turned out to be a bit of a bummer. The Heidts strut tower brace does not clear the hood. It actually stands higher than the fender line. I am guessing it was made with a Camaro car and they did not think of the sloping Firebird hood lines.

I have had the part in the box for a few months because the garage has been too cold to have fun working on the car. Sure hoping Heidts works with me to redesign or return the product. I would rather have a solution than be empty handed.

Update: Fitment of the TBI brace is here, https://www.thirdgen.org/forums/ltx-...ml#post6118260

Tape is at fender height. You can see the front bar is too high.




A dusty old hood insulation mat came in a bit handy. Pretty obvious where first contact is made. It also hits the AC hose. The bar really needs to bow forward instead of going straight from strut to strut.




Points of first contact on driver side.

QwkTrip

iTrader: (22)

In other news, I got a steering shaft from Walter Racecraft that was custom made to my request. It is an Astro steering shaft but the end that faces the steering wheel has been changed out for a 4th gen F-body piece so that the unit is truly a direct bolt-in on the car. Nice little twist to the usual Astro shaft swap that takes it to the next level. Thanks, Matt for taking on this project for me.