The 83GT

BigBlockRanger wrote:I popped the degree wheel and piston stop on, found TDC and then checked the cam position. I put the cam specs into two cam event calculators and both said the intake opening at 0.050" should be 12 degrees BTDC.

I checked it twice and both times it came up 10 degrees BTDC. So the cam as installed is retarded 2°. The lower gear is actually in the "4 deg advanced" position so I am going to have to get a set with more keyways in order to sort this out. That is ok seeing that I have been running this timing set since 2009 or so. Haha.

Be careful with the crankshaft gears. I have two CompCams sets. On one the 4 degree advance is really 0 and the other one is a real 4 degree advance. I am sure you know this, just a reminder to check the keyway cut to the tooth.

Hope it goes well this time.

Yeah, the billet set and the set I just installed are not the retarded version. I made triple sure of that.

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 other way.

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

I'm glad it's running again,when you get the bugs worked out make sure you let us know how that carburetor is working out for you!!

BigBlockRanger wrote: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 because I am still having a weird issue right around 5000 rpm.  The best I can figure is that it is valve float or some sort of harmonic. 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.

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.....

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

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. Whoo hoo!

I have a question on your head build. I bought the same Comp cam springs 925's I too, have the SCJ's that I bought bare. I bought the FMS valves and the guide plates as well. However, I looked and didn't find any FMS spring seats.

I ended up buying Comp 4784-16's spring seats. Is that what you used?

Great build(s) by the way on the 83 and on Green bean!

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 not 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. 

​​​​​​​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.

D8ZZ wrote:

BigBlockRanger wrote: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 because I am still having a weird issue right around 5000 rpm.  The best I can figure is that it is valve float or some sort of harmonic. 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.

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.....

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

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. Whoo hoo!

I have a question on your head build. I bought the same Comp cam springs 925's I too, have the SCJ's that I bought bare. I bought the FMS valves and the guide plates as well. However, I looked and didn't find any FMS spring seats.

I ended up buying Comp 4784-16's spring seats. Is that what you used?

Great build(s) by the way on the 83 and on Green bean!

I can't remember what spring seat I bought off the top of my head, but I think it was a TFS part. I'll try to look at the parts list on my computer Tuesday.

Thanks!

BigBlockRanger wrote: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 not 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. 

​​​​​​​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.

Sounds like the Carburetor is working pretty good!!I have had a AEM AFR Gauge for a couple years now but haven't had the bung welded into the Header Collector to use it yet!!I did take the Mustang for a short drive today and she was running great with the 1050 Dominator on it.And so far no more funky throttle sticking[knock on wood]with the new adjustable throttle bracket!!

BigBlockRanger wrote:I've only bought 3 new carburetors in my life. This is number 3.

Looks like a nice part. Certainly for the price.

I de-choked it and clearanced the Dominator to 4150 adapter plate to clear the 50cc accelerator pump on the secondary side.

I have a feed line on the way to simplify plumbing and I need to connect the throttle cable.

What adapter plate did you use?And is your intake the 4500 Dominator flange?I just read all 11 pages of this thread again very good information in these 11 pages thanks for sharing it with us!!

This intake was originally a 4150 intake. I plugged the holes, opened up the cloverleaf and redrilled it to a 4500 flange back in 2013 or so.

I am using one of the thin MrGasket adapters with the crooked studs to adapt this carb.

You might try pulling the primary jets down 4 sizes, and seeing how your cruise AFR is then, before going after the main air bleeds. If you don't like the WOT AFR with the leaner tune, add the 4 jet sizes to the secondary's.

BigBlockRanger wrote:This intake was originally a 4150 intake.  I plugged the holes, opened up the cloverleaf and redrilled it to a 4500 flange back in 2013 or so.  

I am using one of the thin MrGasket adapters with the crooked studs to adapt this carb.  

I had one of those adapters but didn't know you could use it the opposite way or i would have kept it!!So you flipped it upside down 4500 side to the intake and 4150 side to the carb?If so do you have any pictures before you mounted the carb?I thought about buying a 4500 to 4150 flange adapter if i ever wanted to put my old 1,000 cfm Holley HP annular booster carb on for some reason but the shortest adapter made like that is a 1" IIRC!!Thanks

Yeah, I just flipped it over. I did need to make a small clearance notch to clear the rear accelerator pump. Not a big deal though.

If you need one, just holler, I have several.

D8ZZ wrote:
I have a question on your head build. I bought the same Comp cam springs 925's I too, have the SCJ's that I bought bare. I bought the FMS valves and the guide plates as well. However, I looked and didn't find any FMS spring seats.

I ended up buying Comp 4784-16's spring seats. Is that what you used?

Great build(s) by the way on the 83 and on Green bean!

I can't remember what spring seat I bought off the top of my head, but I think it was a TFS part. I'll try to look at the parts list on my computer Tuesday.

Thanks![/quote]

They are TFS - 41400434

BigBlockRanger wrote:Yeah, I just flipped it over.   I did need to make a small clearance notch to clear the rear accelerator pump. Not a big deal though.

If you need one, just holler, I have several.

Thanks for the information about flipping it over!!I wouldn't mind having one how much would you want for it?I'm guessing you also have the funky studs that go with it?

BigBlockRanger wrote:

D8ZZ wrote:
I have a question on your head build. I bought the same Comp cam springs 925's I too, have the SCJ's that I bought bare. I bought the FMS valves and the guide plates as well. However, I looked and didn't find any FMS spring seats.

I ended up buying Comp 4784-16's spring seats. Is that what you used?

Great build(s) by the way on the 83 and on Green bean!

I can't remember what spring seat I bought off the top of my head, but I think it was a TFS part. I'll try to look at the parts list on my computer Tuesday.

Thanks!

They are TFS - 41400434 [/quote]

Thanks for checking! TFS eh? I fully expected Comp etc. They must be .060 thick or so?

I think they are 0.050"

Mark Miller wrote:

BigBlockRanger wrote:Yeah, I just flipped it over.   I did need to make a small clearance notch to clear the rear accelerator pump. Not a big deal though.

If you need one, just holler, I have several.

Thanks for the information about flipping it over!!I wouldn't mind having one how much would you want for it?I'm guessing you also have the funky studs that go with it?

Yeah I have the studs. Just send me your address.

D8ZZ wrote:

BigBlockRanger wrote:

D8ZZ wrote:
I have a question on your head build. I bought the same Comp cam springs 925's I too, have the SCJ's that I bought bare. I bought the FMS valves and the guide plates as well. However, I looked and didn't find any FMS spring seats.

I ended up buying Comp 4784-16's spring seats. Is that what you used?

Great build(s) by the way on the 83 and on Green bean!

I can't remember what spring seat I bought off the top of my head, but I think it was a TFS part. I'll try to look at the parts list on my computer Tuesday.

Thanks!

They are TFS - 41400434

Thanks for checking! TFS eh? I fully expected Comp etc. They must be .060 thick or so?[/quote]

Looks like .075" thick.

https://www.trickflow.com/parts/tfs-41400434

BigBlockRanger wrote:

Mark Miller wrote:

BigBlockRanger wrote:Yeah, I just flipped it over.   I did need to make a small clearance notch to clear the rear accelerator pump. Not a big deal though.

If you need one, just holler, I have several.

Thanks for the information about flipping it over!!I wouldn't mind having one how much would you want for it?I'm guessing you also have the funky studs that go with it?

Yeah I have the studs.  Just send me your address.  

Thanks i sent you a PM with my address!!

I played with the carb a little yesterday. 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.

Just an idea, hook up the HEI vacuum advance up, and see if your cruise AFR improves any.

BigBlockRanger wrote:

Mark Miller wrote:

BigBlockRanger wrote:Yeah, I just flipped it over.   I did need to make a small clearance notch to clear the rear accelerator pump. Not a big deal though.

If you need one, just holler, I have several.

Thanks for the information about flipping it over!!I wouldn't mind having one how much would you want for it?I'm guessing you also have the funky studs that go with it?

Yeah I have the studs.  Just send me your address.  

I got the adapter plate on Saturday.Thank You Kind Sir

Mark Miller wrote:I got the adapter plate on Saturday.Thank You Kind Sir

Happy to help!

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.

11.52 is about what I thought it might run. Gotta remember that our track is at 3600' and the DA was about 6500'. It will probably run 10.90's at the lower elevation tracks on Raceweek.

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!