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The 83GT... back to BBF

Discussion in 'The Turbo "Builds" Board' started by BBR, Oct 8, 2019.

  1. silver82GT

    Sep 20, 2005
  2. BBR

    Jan 3, 2013
    I was having trouble getting it to run. It would crank up and run, poorly, then would only give a few ka-chuffs.

    I popped new plugs in and monkeyed with the TFI wiring and connector a bit. Turned the key and it lit right off. I dialed in some more idle air and some idle fuel and it idles nice. Drove it around a little and logged it. I didn't hammer on it, just made some laps. Seems to run gooood. Very smooth.

    Pulled back int the shop and noticed fuel dripping from the regulator's vacuum port. lol

    I hate cars.

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  3. BBR

    Jan 3, 2013
    New reg showed up. It's a Mr.Gasket. I have to laugh because people tell you to always buy name brand stuff and not that no-name China crap, but the name brand stuff is made in China too. haha.

    I also nabbed a set of valve springs. The current TFS 16514's (single spring) are a little lighter that what is spec'd by Comp. I am going to a Comp 925 dual spring. They are a little heavier on the seat and open than these. Comp recommends a 924 which is just a skosh lighter than the 925. I stepped up because I read that some folks find the 924 a little light for big block size valves and fast rate lobes like this XE cam has.

    I swapped out the springs this evening, but it wasn't without drama. Haha. I learned an important lesson. You can't find something that isn't lost. :ahah:

    While working on cylinder 3, accidentally dropped the new springs and retainer in the engine bay. They played Plinko and eventually the big spring and retainer ended up on the floor. Ok, so where is the small spring??? I looked and looked. Under the car, in the engine bay, around the starter, I even jacked the dang car up and looked EVERYWHERE. Finally at my wits end, I grab the spring box off the roof of the car and there it was..... :bang:

    I don't know how that sucker bounced all the way up there and landed back in the box. :biggrin-new::biggrin-new::biggrin-new:

    Anyway, the old springs were installed at 1.85" when they were supposed to be at 1.8". That really dropped the seat and open pressures. Totally my fault. With light hyd flat tappet springs, I just didn't realize that small changes in IH mean big changes in seat and open pressures.

    I had a set of +0 locks in the cabinet so I installed the 925's at the recommended 1.90" IH. I also managed to swap them all without having to bust out the air hold. :banana::banana::banana:

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  4. BBR

    Jan 3, 2013
    My friends Ray Meyers and Ed Hohenberg both brought up how close to coil bind the springs are set up with. Too much and the springs can be subject to surging.

    The TFS springs were 0.235" from coil bind. 1.85" - 0.575 - 1.04 = 0.235". This is likely waay too much, which is odd because these springs are recommended for a max of 0.540" lift at 1.80" IH. That would be 0.22" from coil bind.

    Whatever. Haha.

    The Comp springs are closer to their coil bind, (0.15") so that combined with the additional rate, hopefully will clear up the problem.

    I finished up today. It fired right up but I didn't have time to test drive. Maybe tomorrow if it isn't raining.

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  5. BBR

    Jan 3, 2013
    Fix one problem, find a new one.

    I fired up the car and took it for a quick drive yesterday afternoon. Good news is I think the spring surge problem is fixed. I rolled into the throttle (like I did before) and it revved smoothly right up to 5000. On a slow roll, it used to start having problems just beyond 4000. So that is good. The new problem is that dead right at 5000 rpm, something is either causing the MS to reset or overloading the coil igniter or just flat out grounding out the ignition, because it literally just shuts the motor off.

    This caused a mild moment of panic as I was driving down the street. haha.

    It hits 5000 and it's like I just turned the key off.

    2 thing I am going to check today:
    • I rerouted the coil (+) wire the other day from a different source, so I am going to undo that.
    • I am going to disconnect the stock tach and the shift light to eliminate them as potential problems.
    If the problem persists, the old faithful HEI is going in.
    Have I mentioned that this car needs to be rewired??? haha. ooof.

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  6. BBR

    Jan 3, 2013
    Hot wired the coil back to what it used to be. It no longer shuts off but it still wasn't working right. One time it would rev fine, the next not.

    Clipped the wire to the factory tach and shift light. No change.

    I logged it this time and something is causing resets in the MS. You'll rev it and all the data in the log goes to straight lines then resumes.

    Tomorrow I am going to poke the HEI in and see how it acts. I am also going to check the rocker adjustment. I have had one on the driver's side that is a ticker since I swapped springs.

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  7. B E N

    Nov 22, 2016
    Any chance you missed reconnecting one of your grounds? That sounds a bit like EMI in the MS.
  8. BBR

    Jan 3, 2013
    IDK. On Jake's last pass of Raceweek last year, the car popped and shut off. It restarted fine and ran, but something in there hasn't been the same since. Hard starting, noise in the logs, just weird stuff.

    I was hoping it would be manageable until after RW, but it doesn't look like that will be the case.
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  9. BBR

    Jan 3, 2013
    Holy cow this thing is like a rollercoaster ride. I think I am losing my mind.

    I swapped in the HEI distributor and it immediately started up. Set the base timing and it was very happy. Revs perfectly. Then, I look down and there is very little oil pressure. Not zero, but not much. Yikes.

    I pulled the distributor back out and spun the pump with the drill. Made about 12 psi on the drill. I figured something must be leaking internally. I was right. The No. 4 intake lifter had popped up in its bore creating a big leak. The lifter snap ring got damaged a little and the rocker got beat up a little around the pushrod cup. The pushrod looks perfect. I stole a snap ring off an old lifter and put it all back together. Waiting on intake gaskets now.

    How did it happen? I don't think I got it adjusted correctly or I didn't get the set screw locked down tight. The polylock was loose and backed way off and the only way the rocker would get beat up is if the pushrod was still in the lifter. Once the rocker backed far enough off, the pushrod popped out and the lifter popped up. You'd think it would have made an awful noise, but it really didn't.

    I just hope I didn't hurt anything else in the motor with the low oil pressure. It really wasn't making any weird noises, but the front exit exhaust really makes it hard to hear stuff.

    I'm going to drain the oil, pop off the filter and open it up. Hopefully there are no surprises. :bang:

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  10. TurboSnake281

    Dec 13, 2021
    That sucks man, you’ll make it right!
  11. BBR

    Jan 3, 2013
    I put the drill back on it and spun the pump for a bit. Really to circulate oil into the filter more than anything. I almost shot oil out of the rockers like geysers. Haha.

    Pulled the filter and cut it open. That filter cutter worked awesome. There were a few random flakes in there, but nothing that really caused me to worry. I have not drained the oil, but what I dumped out of the filter wasn't gritty and didn't seem glittery so maybe it is ok.

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  12. BBR

    Jan 3, 2013
    It's fine. Everything is fine. Nothing to see here.

    Truth is, I put a billet timing set in it before I knew they really should be used with a bronze cam thrust plate. Since the car is down I figured I would eliminate that lingering worry. Btw, the thrust plate looked fine.

    It's a good thing I did it though, because the crank bolt was loose!

    I have a Cloyes set I am going to swap in. The intent was for a quick swap. Pop off the upper sprocket, leave the lower in place and go on my merry way. The lower is hard to get on/off and there is usually just enough slack that you can eek the upper sprocket on. Well, that did not work as the chains are a slightly different pitch. It's probably for the best though, not mixing parts and all.


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  13. BBR

    Jan 3, 2013
    Going back together.

    The chain in this new set seems to be a lot tighter than the other one. Definitely puts my worrisome mind at ease. Haha.

    I'll finish it up tomorrow. It took me quite a while to pull the old lower off the crank. This crank is a little fat right where the lower sprocket rides so they go on rather snuggly. You nearly always have to rig up a puller to get them off which is hard because of how long the snout is on a.BBF crank. Maybe some day I will make a tool.

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  14. BBR

    Jan 3, 2013
    All back together again!

    I fired it up for just a few seconds just to make sure it would run. It lit right off. I have not put water in it yet because I like to wait and let all the RTV dry good before adding water.

    Swapping the timing set was a good test of how well the engine mount I built works. I have one bolt on each side that attaches to the cylinder head. That allows me to remove the mounting plate and take the timing cover off without having to support the engine in some way.

    Tomorrow I'll double check bolts, fill it up with water and hopefully be done!

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  15. BBR

    Jan 3, 2013
    I fired it up on Friday and everything seems to be good. I took it for a quick spin down the street just to make sure it was going to run right and it ran great.

    Today I took it on its longest drive yet. Drove down Interstate 27 several miles, then got off and doubled back up another road. I stopped and topped it off with some nice 93 octane.

    After that I made a little loop around the I27 access road. There was no traffic so I was able to really put the wood to it. It ran just as expected, with no hiccups or dead spots. I probably stayed in the throttle longer than I should have..... Things were pretty blurry. Haha.

    So I know the question is: how is the carb?

    It's pretty darn good. It accelerates clean and smooth, and WOT afr is a dead solid 12:1. Part throttle cruise is what really needs a little tuning. She's pretty fat at 65 mph and 3000 rpm. I figure the volume of air that 552 cubes pulls at part throttle is a little higher than what Brawler was intending.

    It probably needs some bigger high speed air bleeds to lean it out.

    This converter would probably be perfect with a 3.90 rear gear. It's on the looser side of things, but I feel it's better than the one we ran last year that was on the tight side.

    Overall a very successful drive. Water temp stayed at 180 on the highway and 190 in traffic/slow speeds. Hot crank was a little cranky. The starter didn't want to spin it over when I stopped for gas. Luckily I had the jump box for a little extra oomph.

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    Last edited: May 28, 2024
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  16. MidmoJoe

    Apr 11, 2020
    What an excellent story, I enjoyed it more than anything else on this website. And the excellent technical advice you provided will really help me out on my car.
    I haven’t touched my project for a year or so, but occasionally I think about it. Someday I will be spreading drivetrain parts all over the street in front of my house. Someday.
  17. BBR

    Jan 3, 2013
    I played with the carb a little today. There were a few things I wanted to fiddle with.
    • Lowered float levels because they were right at the top of the sight windows
    • Dropped primary jetting from 80's to 77's
    • Raised secondary jetting from 86's to 88's.
    • Adjusted the secondary stop to balance idle air a little better
    • Richened idle mixture. It was real lean idling.
    Incidentally, the jetting ended up being the same as the Holley 950HP I used to run. Haha. If it continues to be rich at cruise, I will look at an airbleed change to delay/lean out the fuel curve a bit.

    If the weather holds, I hope to take it to the track on Friday.
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  18. BBR

    Jan 3, 2013
    Finally got it out to the track!

    But first, if you want 77 jets in it, don't put 71's in by mistake! I left the shop and the car was acting lean. Drove a little way and decided to turn around and rejet. Got back to the shop, pulled the front bowl off and in the sunlight with my readers on, it was obvious they were 71's. Haha.

    I only had one 77 so I put some 78's in. That made it run much much better on the way to the track. Car ran 185° on the highway, and would cool down when stopped.

    Got out there but thunderstorms were threatening so there were not many people there. I got 3 passes in. First was a bust, trying to figure out what this car wanted. I spazzed and didn't look at a single thing I meant to during the run. 1.57 60' 12.09 @ something. I think I was over revving it and I don't think the shift light is shift lighting.

    Second pass.... Second pass is a little suspicious. I made a couple of tweaks in the pits and went back up. Car launches nice, I shift earlier and the slip shows. 11.19 @ 114.65. MPH seems slow. 60 foot shows 1.17. That ain't right. Weird part is I ran next to a turbo square body that ran 11.20. I got the win light so maybe the 11.19 was legit. Idk. Car did feel good.

    Weather was closing in so I decided to go make one more run before packing it in.

    Car seemed a bit warmer at the line than normal but I made a pass anyway. 1.56 60 foot, 11.52 @ 114.4. By the end of the run she was plenty hot and getting hotter. I rolled it down the return road, shut it off and coasted as far as I could. Stopped right by a buddy's race trailer. I popped the hood and immediately saw that the alternator belt had left the chat, taking the electric fan wiring with it.

    DA was 6500' tonight.

    Great. I was all set to just make a pass, go back, swap tires and go home. Nope. I got the track guys to tow me back to my Raceweek trailer just as it started to rain. I secured the car and trailer, left it there and my buddy Jonathan came out and gave me a ride home.

    I will go back tomorrow and retrieve it during their bracket race.

    Better to figure this stuff out now and not on Raceweek!

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    Last edited: Jun 14, 2024
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  19. BBR

    Jan 3, 2013
    So for those keeping score, the head/cam change dropped around a full second off this car's ET in Amarillo. Maybe more once I get a handle on what it wants for timing and shift points.

    For comparison's sake, the original 545 spent most of its life in the bottom 11's here. Once running 11.19 something like 3 times in a row. It was a struggle to finally make a 10 second pass here. At other tracks with good air, it ran mid 10's like clockwork. If this thing sees a 10.99, I'll have Judd do a backflip for me.

    Oh yeah, I checked the shift light. No lighty. Gotta figure that out this week.

    Haul of shame back to the shop.
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    Last edited: Jun 15, 2024
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  20. nxcoupe

    Jan 10, 2008
    Hooe you get it back together quickly and cheaply. Can you post pics of how you transport your trailer and car on the car trailer and maybe some detail on your raceweek trailer? I'm gathering info to make a plan to build mine, thanks!
    BBR likes this.
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