I don't believe they are hardened in any way but I'm not 100% sure. I know when my local machine shop "turns" a crank, they remove a decent amount of material from the journals then use oversize bearings to make up for it, and they do not do anything to the crank other than cut and polish it, no hardening or anything.

I use a tap on the head bolt holes in the engine block because the chaser never seems to "cut" the thread sealant I use, and it feels like it is going to strip the threads out rather than remove the sealant. Carefully using a tap the stuff comes right out.

I'm soon going to be swapping the D36 for a D44, and installing polygraphite bushings everywhere while I'm back there. I know what all needs done and what all parts are needed but have never removed or installed an independent rear myself.

Can anyone tell me or give me a link to a thread that has the step by step process? I can easily see what all bolts and such need removed to drop the diff out, but what should be removed first, and what is the order of install on stuff like the batwing/driveshaft/diff/etc.? Is there a way to do this without needing a new alignment? I was thinking of marking all the adjustment points so I can reinstall them back to where they were.

I hate them. They have 25% of my income over the last 15 years.

Just kidding. They are great. I also order one morning and have my stuff the next morning. Been to the showroom once, it is awesome!

If it's the AFPR, you will have fuel squirt out the vac line nipple while cranking. Pull the vac line off and see if it is wet. If not, start the car or crank the car while watching where the vac line hooks to the AFPR. No fuel coming out, likely the AFPR is fine.

You will be fine for a little while without the trans cooler as long as the outside temps are not sweltering hot, the converter isn't a huge stall converter, and you don't beat on it alot, and you still have it locking up on the highway. Put it in whenever you can though, the sooner the better.

Bone stock ignition, either will be fine.

MSD or Crane or whatever ignition, either will be fine. I've used both. With an aftermarket ignition it is critical to keep them from touching metal. You will be able to go out in the dark with the hood lights unplugged and see the spark jump right through any wire if it is touching metal. Best to cut to length and put your own ends on if using aftermarket igintion boxes. Haven't found this to be true on stock ignitions but might be.

Use heat socks around the headers if you have headers.

But again, as far as brand, I've ran both and both seem the same to me.

For plugs, getting the right heat range and gap is more important than brand. That said, I prefer NGK's for stock and mild to moderate performance applications if you are looking for iridium plugs. For copper, I prefer Autolites. For nitrous/boosted, I go with Autolite Racing series plugs as they are non protruding electrodes.

When battery is disconnected, then reconnected, it always defaults to AC on when fired back up, which makes the fan run. You are fine. Dodged a bullet for sure.

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I have my front sway bar removed to let the front end lift quicker for drag racing. (it works great, btw) It does ride MUCH softer in the front, which is kind of nice on the rough roads around here. The drag radials in the back soften up the rear ride.

Anyway, just be careful on the twisties. Bore it into a corner and be hard on the brake at the same time and it feels like the back end wants to come around. But the drag radials won't let it break loose, so it makes the front VERY twitchy, for lack of a better term. You MUST be VERY smooth on the steering going into a corner hard or you will pile it up. If you plan on any spirited street driving, keep the front sway bar hooked up. If you are just a cruiser and/or drag racer, unhook it and enjoy!

If you are SURE you are never going to spray nitrous or anything, go with a cast or SIR crank, and hyper pistons. I'd used a forged I-beam rod in that engine, but that's me. 5.7" would be a good choice.

Don't get the static compression very high with that cam in a 383, or your dynamic compression will be too high and you will have problems on pump gas. That cam isn't going to "bleed off" much compression.

You said you have the choice of 2 intakes. Figure out which intake you are going to use first. If you are considering a miniram or LT1 intake, that cam is too small. If a TPI, ok, but you will have a serious torque monster. If you are looking at using a superram or HSR, consider selling that cam and getting a 219 or 224 intake duration. The one you have will work but you are leaving a good deal on the table with anything other than a reworked TPI intake.

Ron (cuisinartvette) was porting these for people for a small fee I think. Don't know if he still is or not. Contact him, maybe you can send it to him for a port job and he will send it back and you will be happy!

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Truer words have never been spoken.

More addicting than tobacco.

More addicting than beer.

More addicting than liquor.

Ranks right up there with sex, actually!

If you are staying with a long tube runner setup, run the 2nd cam you posted in the original post.

Better for you would be to put on a Superram or HSR intake, and run a LPE 219 cam. A CC503 (224/230 duration) cam WILL need serious fine tuning and a higher stall converter to end up with stocklike street manners, and a high stall converter is NOT stocklike street manners in itself. IF you want near stock street manners with the most HP and Torque you can get, again, run the 2nd cam you listed, or run the LPE 219 with a superram. Low 12 second combo for sure.

Make SURE your heads are set up to accept the valve lift you are throwing at them. I didn't check, they may be able to in their out of the box configuration, or maybe not. Make sure before you buy the cam if you don't plan on doing any head/valve work.

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I would have to agree that for sure your goals will be attainable by freshening your combo, then sticking the AFR 195's on it. Would be the cheapest since you already have the cam. Maybe go up a hair on your converter stall.

But, you know you can't take your eyes off that 400+ cuber sitting there waiting to catapult the 'vette down the strip. A hair more cam, a hair more converter stall, and a miniram. Blow your goals out of the water!

I have the 230/236 cam and a HSR intake and AFR 195's and am running about the same times as you. I know my car is heavier, and gearing is hurting me a little, and it is a flat tappet cam and isn't dialed in yet but even then the gap between us won't be that much. I almost wish I'd have done the 219 cam.....

Either way, let us know what you decide!

U planning on doing this rebuild this year, or is this a winter project?

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LOL! I just spit beer out my nose!

My original goal on this setup was a 10.7 on a 225 shot. I'm up to a 250, but I think my solenoid is maxed out, think I'm getting about a 230 or so. Bottle pressure was only 900 with a heater, need to add a 2nd heater. I honestly think with higher bottle pressure, tune dialed in more, and 3.45 gears I'll get down to a 10.40, possibly a 10.30.

When my converter locks just after the 2-3 shift my rpms are dropping down to 3950 with the 3.07's. With 3.45's it will only drop to about 4400 or 4450, and will then get up near 6000 rpms when crossing the stripe. Should be perfect. I know most don't gain much from a gear change with an auto but I'm still dead hooking the launch so I don't think tire spin will slow me down with the new gears, and I think the more optimal rpm at the big end of the track should help me out .1 or .15. Time will tell!

Yes, I did know it was on borrowed time for sure.

Can't afford a solid rear, not by a long shot. Hoping that the D44 conversion will survive with my rolling into the throttle on launch instead of matting it right to the floor.

I am on my way with the part gathering.

D44 chunk with 3.45's lined up for $500, should get it in a couple of weeks.

D44 C-beam and driveshaft together for $100.

Just ordered rear bushing kit from p-s-t

45 tooth speedo gear ordered. I should use a 15 tooth drive gear and a 43 tooth driven gear. I have a 17 tooth drive gear, which would require a 46 tooth driven gear with the tires I'm running. I think the 45 tooth should put my speedometer real close, close enough to not pull the tailhousing and mess with the drive gear. If it puts me within 5 mph at 65 I'll be happy. Anyone know how much the speedo will be off with that combo? I'm guessing about 3 mph at 65. Heck, it's off about 3 now even though by calculating it should be dead on.

Still looking for a D44 batwing. I'll buy one of C409's adapter plates and drill my D36 batwing before I buy a new one for $650. Hate to use an adapter plate but if I can't find a used D44 batwing at a reasonable price in the next couple weeks that's what I'll do.

Thanks, I'm going to have to look into it!

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my thoughts exactly!

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I sure wish someone made a bolt in cage, something that could be removed, then bolted back in for track days, then unbolted again. Maybe something that requires and hour or so to remove or install. I'd buy one.

Just can't picture driving down the road with the top down on a hot summer day with the wifey's hair blowing out through a big ugly roll cage!

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Buy a 'vert. I did.

If I were you, and could afford a new block and such, I'd do a 434. Put that superram, 195 eliminators and a decent cam in there and you would have stocklike street manners and a serious torque monster. But.....

You will likely snap the independent rear, even if it is a D44, with all that torque. With a 383 with the eliminators and superram and combo you have, 11.40's will be a stretch (likely doable with everything matched and dialed right in), but 11.80's are easily do-able. Of course a huge cam and stall converter would put you in the 10's but goodbye street manners. My combo isn't all that far from yours, and I just ran a 12.08. That's with a tune that is still getting better and better with changes, and a 3520 lb raceweight, and 3.07 gears. My cam is a 230/236 flat tappet, probably giving up .1 or .2 by running a flat tappet too.

If you can do the 396 with the 195 eliminators and get a cam and converter stall matched up good but not too small to over torque the rear but not too big to kill street manners I would think you would be running 11.40's or better all day long. A 230 duration cam, .575 lift, 2800 stall, 3.45 gears, should be an awesome combo in a 396 with great street manners. JMHO.

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Ooh, if that's the case, put a 150 shot to it. It'll seal right up.

I have an Eagle forged rotating assembly with JE pistons, and custom billett splayed main caps. Main caps don't mean much since I'm only revving to 6300 but....

I've detonated on motor alot working out the tune, detonated on the spray more than I'd like to admit on a shot bigger than a 200, melted the spark plugs completely, porcelain and all, and melted the exhaust valves on the new AFR's. After all that, the shortblock has no blowby whatsoever and is performing flawlessly to date, running very bottom 12's on motor and mid 10's on spray.

Point is, an off the shelf rotating assemby from Summit and your skills can have you a nearly indestructible 383.

What did it normally run in the 1/4?

Any idea what killed it? Normal wear over time, or detonation, or ???

How much cabbage you looking to spend on the next build, what are you looking for power wise and all that?

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Yes. I revved a stock 350 bottom end to 6200 rpm shift points for a season with no problems, but that was with an HSR intake and other supporting mods so that was about the optimal shift point for me.

For you, I'm guessing 5500 to 5800 shift points, I'd set the rev limiter around 6000 or 6200.

Man Pete, that's too bad. I wanted to come down Sunday but I couldn't. Wasn't planning on saturday because I was to be busy then too but my schedule opened up and I figured I'd run down and make a few runs. Was nervous as I drove theh car there 1.5 hours 1 way, would suck to be broke down.

Did you drive your car there and then have to make arrangements to get hauled home?

What did you break?

Did you get any runs in? If so, what were your times?

At the track I have maybe 15 1.6X passes and maybe 8 1.5X passes. I really think coming out of the burnout to heat the tires is what was the hardest on it. I try to ease out of it but it still isn't the smoothest. The ET street radials are much stickier than the Nittos were and it could really be felt when ending (and even during) the burnout.

You are correct that it's no crying shame, and it is still holding up fine other than a clunk when I make a sharp turn and some gear whine on the interstate. Hopefully it will get me through till I round up a D44 chunk, batwing, driveshaft, and maybe C-beam. I might redrill my D36 C-beam, and I've heard the D36 driveshaft can be used as-is but then there isn't much clearance at the trans. I'm still searching for more info on that one to be sure.

I have a good line on a D44 centersection with 3.45 gears, but the hardest part is going to be finding a decent priced D44 batwing. Anybody have one they will part with at a reasonable price??

Man, I hope you just walk away from it for a while, come back to it in 6 months or a year. I was about ready to get rid of mine, now I'm very glad I didn't.

Yes, my afr's are the 195 Eliminator street ports. My cam is a flat tappet 230/236 duration cam on a 110 lsa. I really think I'm giving up quite a bit with that cam, someday I'd like to do a 236/242 hyd. roller on a 113 or so lsa.

My mph is really surprising me too. Going to have to do the J55 upgrade this winter. I have Hawk HPS pads front and rear and a bias spring installed but it still takes alot of brake to get it woed down at the end of the track.

The biggest tuning problem with this combo is, when it shifts to 3rd and the converter locks, the rpms drop down to about 4000. That is right about the torque peak, and right where it is most prone to detonation. I have the timing way back in that area and ramp it up quickly after that, but if I lean it out to upper 12's or bottom 13's air fuel ratio it detonates. I have it running 11.7 to 12.5 air fuel ratio to keep it happy. High compression, small efficient combustion chambers, capacitive discharge ignition and a few other things all contribute to a super fast burn. I'm currently running 26.5 degrees from 4800 rpms up, and only 21.5 degrees at 4000 rpms. That is on motor, I retard 10 degrees from that on the spray. Isn't much timing but it's what the engine likes.

Guess the 3.45 gears will somewhat fix that because the rpms that it drops to after the 3rd gear shift and the converter lock will be 4450 rpms, and should pull up towards the redline harder with the lower gears. I'll be crossing the stripe at around 6000 rpms instead of 5350 rpms. Should make a difference.

Are you serious? MAN I hope he isn't selling it. Don't want to lose him on the C4 forum. JOSH????

I'm very happy with the manners on my AFR headed 383 with 230/236 duration cam. Slight surge and 2800 stall are the only things that keep it from being stock mannered. If I were to drop down to a 224/224 cam and a 2000 stall converter it would give up a little time in the 1/4 but would likely still run 12.50's on motor.

I love the HSR but if you are on a budget you would be better to do an LT1 conversion intake or buy a used miniram. LT1, Miniram, HSR or Superram, you will be happy with any of them. Build all else with used/budget parts but spend on the shortblock and the heads.

....but I think I broke the D36.

Ran first pass motor only, beat my old best by .14 and 2 mph. Didn't launch as hard as I could have. Was pinging a little on the big end of the track and was a hair lean. More in it for sure. Fixed that when I got home but didn't have laptop at track to fix it and run again. Today, on motor, it was:

1.666 60ft
7.68 @ 88.42 in the 1/8th
12.08 @ 113.15 in the 1/4

Then I sprayed it. Started with timing backed down and snuck up on it over a few passes. On a 250 shot but couldn't get the bottle pressure much over 900. My big bottle needs another heater! Results:

1.551 60 ft
6.79 @ 102.44 in the 1/8th
10.55 @ 132.78 in the 1/4

After this pass I heard a clunk in the rear when I turned onto the return road, then heard the gears whining slightly when driving back the return road. Figured the diff was shot. Ran it again anyway because I was at 10 degrees retard on the spray and wanted to try 8. Last pass launch was fine but it detonated here and there just a little during the pass so I know for sure the 10 degrees of retard is what my nitrous shot likes. Same clunk and same whining on the return road. I packed it up and drove it back home (track is 1.5 hours from my house) and it made the drive home fine.

After I got home I tweaked the tune and ripped it around a while, tweaked again and ripped again, rear is still holding up fine, but it clunks when turning hard and whines a little on the interstate. Not sure what is wrong in there but I'm 99% sure it is internal. I'm surprised it hasn't grenaded since I'm still beating on it. Don't think it is a U-joint, I'll check it out for sure tomorrow.

Looks like it's time for a D44 and 3.45 gears!

I'm running the single nozzle that comes with the Zex kit. The fuel and nitrous lines both hook to it. It is installed behind the MAF, in front of the throttle body. Was on the side of the intake duct but the right side cylinders ran leaner than the left so I moved it to the bottom, dead center. I did have some front to rear distribution issues, not to major though. I ported the heck out of the tops of the intake runners on the front cylinders but left the back unported. That seems to have straightened it out pretty good. All plugs now look about the same.

I'm running a Crane Hi-6 CD box, with the TRC-2 timing retard box. When I hit the nitrous switch it also activates the retard box, so I only get the retard while the nitrous is spraying.

I found that 150 to 175 shot on a stock-ish compression motor is pretty much an out of the box install with just retard timing some and make sure it isn't lean. When you get up to spraying 225 or more and on a high compression engine, the wideband 02 is prettymuch worthless. My wideband reads around 9.8 to 10.5 while spraying, but then after the run it reads all screwy for a minute or 2, almost like it gets too hot and messes up till it cools down. Plug readings are the only way to go with big shots. Also, your plugs need to be really cold. It took me a while to find plugs cold enough to spray that much, but hot enough to not foul out during lots of part throttle driving. I ended up with Autolite Racing AR-3933's.

I borrowed one from my brother, but many salvage yards have one sitting around that they will loan or rent you for dirt cheap.

When I removed my engine I didn't pull the radiator or any of that. Actually never unhooked any of the A/C lines or the power steering lines, just swung the PS pump out of the way, and I slid the condenser canister or whatever that cylinder on the radiator for the A/C is called up out and then had enough room to swing the A/C compressor out of the way. Never lost my A/C gas that way.

Since I don't have an engine stand, I tore mine down to the shortblock while it was in the car. With the heads removed you can remove the upper bellhousing bolts from above with a ratchet wrench very easily. Made the time under the car alot less, which is a good thing!

Now is the time to do long tube headers also, try to fit that into the budget while doing the engine work.

Not sure if you are an auto or a stick but consider converter or clutch now.

Are you doing a performance build or a stock rebuild or somewhere in between?

LT1 exhaust is much better than an L98 exhaust and will bolt right up if you get the hangers and all. Shop on CF for a used one. I know the LT1 catback is all stainless, I have one on my '89 right now. Still looks like brand new, and I paid $50 for it.

I'm running a Zex kit. Had to change the -3an feed line that came with the kit from the NMU to the intake to a -4an line and drill out the fittings to the same size as the inside of a -4an line because the -3an line was only as big as the 175 jet. Also had to drill out the nitrous side of the nozzle to make it big enough for more than a 175. Now I'm up to 250 and the solenoid in the NMU is maxed out. You know me, I do whatever it takes to get the best results with the least amount of money spent.

I love the Zex kit because if the bottle isn't fully hot yet I can still spray and not have a rich mix, it just won't give me the full 250. Regulates the enrichment fuel to match the bottle pressure.

I have a walbro 255hp in tank pump, direct replacement of the stock pump. Lines are all stock except for the braided steel that go from the filter to the fuel rails up the back of the engine. Holley rail mounted regulator. I only run about 37 lbs fuel pressure because I don't want a big pressure/volume drop when I hit the spray. The lower pressure also helps the pump keep up, they pump alot more volume at lower pressures. Although, I have never had any fuel starvation signs, symptoms or issues but keeping the base pressure a little lower keeps me more on the safe side.

I'm ready now for the race on pump gas.

Probably going to have to do it at separate drag strips and post the times and the times adjusted to DA since we are all over the country.

If I get beat then I'll have to try the race gas thing sooner. If it picks up alot of power on race gas and more timing I will consider a small water/meth injection kit so I can keep the added timing and still run pump gas. Don't want to spend any more on performance mods right now, but....


JOSH....hurry up and run a bottom 10 to get me re-motivated to performance mods. Or, run a high 10, save me a bunch of money, and get out your pink marker!

I'm really hoping to get to the track soon to get it completely dialed in on motor and spray on pump gas. It is very close.

Then, I hope to go 1 more time late in the year, fill it with a tank full of race gas and start making nitrous passes. Won't mess with the motor tune but I would like to try this on spray and keep adding 2 degrees of timing between passes till I start finding any signs of detonation on the spark plugs, then go back down a degree or 2. With the amount of compression I'm running (11.4 SCR, 9.2 DCR) and spraying as much as I am with only 383 cubes, I have a feeling race gas will really help my ET and MPH. Would be nice to try anyway. Plus it's easy with the timing retard box, just turn the knob.

Also hoping to get a D44 in it this winter or next winter and run 3.45 gears. I think the 3.07's are killing me when the converter locks up on the big end of the track. It's dropping the rpms way below the powerband. 3.45's will be good and still give me a little room to grow.

Drove the 'vette for the first time in a while. Been too busy and almost always have the kids, not enough seats in the 'vette.

Worked the N/A tune a little leaner. Went too lean and picked up a little detonation, so I went back a little. Started at mid 11's AFR now I'm at upper 12's and all is well.

Sprayed it with the 250 shot. Felt a little miss at around 120 mph, just a couple very quick single cylinder misfires. Brought back, pulled plugs, can see some very minor speckling of the porcelains. Was plenty rich on the wideband and timing is retarded 12 degrees for the 250 shot. Anyway the peppering is very very mild and under a magnifying glass is all black so all is fine with the powerplant. Plugs are pretty clean looking and have a nice fuel ring coloring just like they should.

Then I found my #8 plug had almost no gap at all. I then remembered dropping that one when I installed it last time but never looked at it as I was in a hurry. Stupid. I looked very close and there is no sign of anything contacting the plug. Anyway, I think the slight miss when spraying was likely from that plug having nearly no gap and the flecks on the plugs was from the previous detonation.

Haven't sprayed again after putting in a new #8 plug but after this run I'm sure I have picked up alot since the last track trip. Being that I ran a 10.66 on a 225 shot and spark plugs with no ground straps surely I'll get that 10.40 now. Sure feels like it. Seems to pull alot harder now than before.

Anyway, just wanted to chat a little about how happy I am with my C4 and glad I stuck it out when the times were tough with it. I think, other than a rear, my performance mods have reached their end for quite a while. I couldn't be happier with the way it runs and drives and hooks up and romps everything I match up against on the street. Next purchase barring any break downs will be new sunvisors and new seat covers. Time to finish the interior and the little details!

Looking goooooood.

I need to do this. I'm still working out of a gravel drive.

Wow, that calculator just picked me up a tenth and a half! HAHA!

Cool calculator, thanks for the link.

According to that, the DA was 1803 when I ran.

Calculator shows a corrected run of 10.532 @ 132.841 mph.

Actual run was a 10.66 @ 131.08.



Next time out I'm going to run an actual run of 10.47 @ 132.5. I'll post it up and let you know if I'm a good guesser or not.

If it is running and driving good then the rich part throttle and the lean WOT should be an easy fix. You will likely need to get a laptop and cable and datalog, then send the datalog to TPIS for a tune tweak. If they don't do custom chips, see if they will email you the .bin file for the chip you have. Anyone with tuning capabilities should be able to pull the file in and make some changes.

Tune perfection will not be accomplished unless you start tuning yourself and devote hundreds of hours to it, but a few changes and a few tries from a mail order tuner or TPIS, if they do that, should get you dialed in if that's all it needs.

Is this a MAF setup or a SD setup? I'd be willing to help you out with tune tweaks, but I'm better with MAF than I am on speed density setups.

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Good catch prOzac. I missed that little edited by CC. Now I'd love to know too!

You need narrow body, self aligning roller rockers. You will need to grind the drip tabs off. They hang down from the underside of the valve covers. I originally installed mine without removing the drip tabs. Upon starting the car all the drip tabs snapped off in the rocker slots, preventing the rockers from being able to move, and bent all my pushrods. Luckily new pushrods was all I needed. Make sure you remove those tabs!

You may (but shouldn't) have to modify the breather baffle a little with a pair of vice grips. Depending on the actual rockers you get, they may rub the sides of the baffle in the valve cover. It's simple to crimp them in a little with vice grips and all will still work fine.

U R pretty close to Richmond. Going to the Nascar race this weekend? If so, gather up the friend that loaned you the rear and come meet me. My wife and boys and I will be camping and partying there with a couple other friends Thursday through Sunday. I'll supply the beer and burgers. If you are coming let me know, I'll pm you my cell number.

From what I've heard and read the LT1/LT4 heads, when ported, are very good. If you were asking about the L98 113 casting heads I have some experience there, and I can tell you that as soon as the long tube runner intake and restrictive exhaust manifolds and exhaust system is gone, the heads become restrictive, even when ported and bigger valves are installed. Then the bigger the cam you are running the more restrictive they are. There are huge gains to be had with a head swap on an L98 once you get the stock intake and exhaust in the dumpster.

If I was a bettin man, I'd wager anyone that the next time out he will be 2-3 mph faster than his fastest pass yet. I was puzzled until I realized the short times were from bogging, not spinning. Now I'm 100% sure the 1/4 mile ET and MPH will be better once dialed in. This is one of those things where it won't show on a dyno but real world results tell you where work needs done.

I'll agree 100% that the tests were conclusive as to the gains from the AFR heads. One can speculate all day about the 60' times effect on the pass, but as stated above the AFR's were quicker from segment to segment on the track, backing up the dyno results.

I am impressed at your success this early in the tuning process. I originally thought (when on the TFS heads and until I read this thread) that your 60' times were traction limited, rather than power or launch technique limited. I'm sure with some tuning of timing and fueling in the right areas and learning the launch style that the combo likes you will get to where you want to be.

As a side note, I wonder what the drop down rpm is when you bog. If it isn't too low, sounds like that would be the perfect time to hit the spray switch and not blow the tires off. Maybe you are set up more for nitrous already then you know you are??!! And since your car is a street car maybe that bog will give you that much more traction on the street?? Lots to consider, but, no more need to consider which heads to run!

Either the throttle blades are hanging open for some reason, which can be fixed with a spring, or possibly the IAC valve is sticking. IAC is more likely.

Next time it hangs up pop the hood while the idle is up and see if the throttle is against the stop screw. If it is, then it isn't hanging open and the extra air is coming in from somewhere, likely the IAC valve.

Remove the IAC, clean it, clean it's housing, and put it back in. I've cleaned mine several times, till eventually I had to replace it. Same problem as you only my idle would only hang at about 1300 rpms. Turning the A/C on and off would free mine up from sticking at first but eventually not.

Could also be the IAC throttle follower in the tune needs tweaked but if it worked good before then that setting is likely fine.