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  #1  
Old 08-24-2002, 03:39 AM
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Wesdog Wesdog is offline
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Hey guys, it's been quite a while since I posted here. I have a 76 S Chief which I have put lots of work into, especially the engine. I am about to pull the recently rebuilt 401 back out to install new 401-SRK Aluminum Heads from Indy Cylinder Head Inc. You can see their products at: http://www.indyheads.com This is a new AMC product line they recently developed. They worked with Edlebrock on the design according to the guy I spoke with at Indy. The new heads will accept stock and aftermarket intakes but raise the overall height about 3/4". Filler pieces are required between the intake and block on both ends of the block rails where the rubber oil seals sit. Won't have more details until the work is done. Indy also sells an intake (that can be setup by them for EFI if you want) but the height may be a problem unless you have a body lift kit - which I don't - yet! Any suggestions?
I am currently using an Edlebrock performer cam and intake. I have a new 800 cfm Edlebrock 1413 carb to sit on top of the intake (moving toward EFI slowly). Haven't decided on the final cam yet but will probably stay with the current Performer. I would like to end up with more power in the 350 - 400HP range (at the crank) with additional low end torque but that is probably not gonna happen this go round without changing pistons and cam. The kit comes with fully assembled heads 1.6 roller rockers, guides, pushrods and studs. The intake port volume is 235cc which is 69cc larger than stock. It features a modern high quench heart shaped 61cc combustion chamber - this is 3cc larger than the stock 58cc chamber size so without a piston change or head milling I will be loosing a small amount of compression for now. I'm hoping the chamber design is the answer to the knocking problems in these motors. There is no exhaust crossfeed port on these heads so the intake stays much cooler. This also makes them 'legal for offroad use only'. Since there is no exhaust input to the intake there is no EGR exhaust gas source. I will be tapping into the exhaust system and plumbing a line to the EGR plenum on the rear of the intake to supply exhaust gas so the EGR will work (when I want it to). I live in Los Angeles and I need to pass future smog inspections. I just got my 2 year certification so I have some time before I have to do it again to work out any 'issues'. The EGR actually has value in preventing pre-ignition and the formation of NOX gases which pollute the atmosphere causing the deterioration of the eco system leading the eventual extinction of all life on earth, but then again, it does potentially reduce horsepower so it needs to be setup correctly or maybe it could temporarily develop a restriction.
I've previously posted about a year ago regarding my cooling system modifications. I worked with the engineers at Evans Cooling and my mechanic to develop them. I'm sure other on the list have their own simuliar setups. Mine consisted of a custom highflow waterpump, aluminum crossflow radiator, Evans coolant, dual electric fans and additional cooling lines plumbed from the rear of the intake to an adapter under the waterneck. Heat and pre-ignition eventually killed 2 previous engines so I went a bit overboard on the cooling system this time. You should see the gauge setup I've been using to verify the engineering of this. In addition to the stock cluster, I have had 3 mechanical coolant temps, mech oil temp, mech trans temp, pyrometer in #1 header tube, intake vacumn, volts, and 200 amp add-on gauges all going at the same time. I've cut back on the coolant temps now that I am confident things are working correctly. Gotta go now.

Wesdog

[ August 29, 2002, 07:23 AM: Message edited by: Wesdog ]
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Old 08-24-2002, 10:12 AM
andy d andy d is offline
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the aluminum heads should help a lot with heat dissapation. i dont really understand the need for 400hp in a jeep. why not in something with 1/2 the weight and some handling ability? my wag is scary over 70mph. to each his own i guess [img]smile.gif[/img]
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Old 08-24-2002, 10:44 AM
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I have looked at these heads before but have not been sold on them yet because 4 out of 5 of the pro mechanics for AMC that I have been able to get in touch with said the heads were never a problem after the Dog leg design. And after watching H/P TV's build up on there 401 with stock heads(3 angled and magnafluxed with new valves etc.) they got 485 H/P at the crank and 425ft pds at around 2700. I have always been told that the biggest problem with the AMC's was the Intake and asperation(sp?), oiling to the rear mains, and smog restrictions. Dont get me wrong I would love to get my hands on a set of these heads(if I had the money) but to me the real benifit is when they offer an affordable multi-port fuel injection system. Please let me know what your power gains are--I would be putting them on a 360 experiences/parts have ruled out a 401(am jealous of any one who has a good one!!!ha!) and I am really looking at the roller rockers I really think if I combined those with roller lifters(available from dodge) you could get up to 50 more H/P and really decrease heat. Kirk
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Old 08-24-2002, 01:59 PM
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The Indy heads seemed to be the biggest bang for the buck for me at this point. I want additional torque and horsepower but am concerned about the 401 block's thin cylinder walls and potential for overheating and resultant component damage, especially with a 0.030 over rebuild. The extra heat dissipation of aluminium heads and the modern chamber design make these heads a superior choice to reworking the stock heads for my situation. It's not the money at this point. I bought my 76 S Chief in 1980 with 30k miles on it. It now has 230k miles on it, all with 401s. I am very familiar with what can happen when things go wrong. Been there, done that a couple times in the last 22 years.
I doubt there will ever be a smog legal, aftermarket MPI kit for the older AMC vehicles and engines - not enough market potential to justfy the certification costs. So affordable, street legal MPI for older FSJs probably isn't in the cards. I'm certain there are others on this list that know much more about this than me, but that's my view of the situation. I will play the game and put the carb on when needed for smog certification in the future after I convert to EFI.
I currently plan on modifying a EGR capable Torker manifold as my EFI intake. Its runner size is very close to the Indy head intake port size. I found a company called 034 EFI http://www.034efi.com that makes a reasonably priced controller that has all the interfaces and features I am looking for. They also sell bungs and fuel rail stock for a lower price than other sources I tried.
I'm looking for more horse power and torque cause I'm tired of limping along with a fully loaded vehicle on long uphill grades. I'm not looking to go 80 or 90 mph, but I do want to be able to cruise uphill with a load at 70 and not be in the way of other traffic. I know these motors can do it with our vehicles when setup correctly with sufficient cooling capacity. I have a TH400 and part-time Q-trac. My rear end is a custom full floating Dana 60 with 3.54 gears and limited slip TracLoc. Most of my driving is highway but I do use the vehicle offroad on occasion. I have considered going to different gears but will wait to see how the vehicle performs with the new heads before making that decision. I hope to get some tuning time on a dyno when the install is complete.
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  #5  
Old 08-25-2002, 05:48 AM
RWC RWC is offline
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I hate to tell you this, but you're not going to see much of an improvement. I didn't see a degree of temperature difference after installing my heads, and while I did notice an increase in power, I'm not sure that I can attribute all of it to the Indy heads since I also swapped cams. What has suprised me to learn over the last year is just how capable the dog-leg AMC heads were straight from the factory. After having blown all kinds of cash on the Indy heads, I'm really not sure it was worth it, especially considering that they weren't even close to a stock bolt-on procedure. If you want more info on the Indy heads, check out pub8.ezboard.com/bamcforum and scroll down a little way in the engine modifactions section. Somebody compiled all the discussions on the Indy heads recently, both good and bad. My personal opinion is that it's highly unlikely that we in the Jeep world will ever build an engine that can even come close to taking advantage of what the Indy heads have to offer (although I'll be trying this winter when I transfer the heads over to a 401).

That being said, if money isn't a problem, then got for it! AMCers need to buy LOTS of these things for the aftermarket to realize that we're serious about AMC engines!

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Old 08-25-2002, 05:51 AM
RWC RWC is offline
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Oh, the other option for aluminum heads are the HLR (Herman Lewis Racing) heads. The Indy heads are probably a better piece, but HLR has better support.

RWC
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  #7  
Old 08-26-2002, 01:21 PM
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RWC, Thanks a bunch for pointing me to the amcforum! I read through the Indy head archives and it was very infomative. Got lots of other great info also. Wish I would have known about that list a couple years/tears ago. Anyway, I am probably gonna keep my edelbrock performer cam and intake for now and use them with the Indy heads. Won't be able to get the kind of torque and horsepower numbers I wished for but all in all I'll have a better performing motor that will hopefully be much less prone to pre-ignition with extra heat dissipation on the top end.
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Old 08-26-2002, 03:52 PM
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I have to ask a question. How are you going to utilize a set of heads which I would think are designed to develope lots of horepower and torque at high rpm in a 5k truck going 65 up a hill at 2500-4000 rpm? Will you just stick it into 2nd gear(auto) and wind it tight? I don't think I could handle listening to it. I'm not trying to be rude but I just don't think it's real practical for something used as a daily driver and I'm pretty sure I wouldn't want to be running a trail at 4000 and up rpm. J20
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Old 08-26-2002, 05:22 PM
reddog reddog is offline
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I am curious how that passes smog here in L.A.?? Is all the stuff you have on there CARB certified or do you go to the referee?? Can you also tell me about your waterpump? What kind of mods are done to it?? TIA

Kerry
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Old 08-27-2002, 01:08 AM
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Kerry, I had all the required smog equipment on my vehicle for the smog check I just completed. I also have a hi-flow cat that I wasn't required to have on a 76 with 401. My numbers were very good. Some of my equipment is indeed not CARB certified, the DUI distributor for example. However, the extent that the CARB certs are checked varies station to station. I went to a 'test only' station that my mechanic recommended. Actually he took it there for the test. I have all the original equipment in case I have to put it back for testing. It runs cleaner with my current setup but I will play the game if they make me. The bottom line to me is what comes out the tailpipe.
Regarding the waterpump - I'll be happy to email some pics. Email me offline at wesstepp@attbi.com. I sent my stock pump to Evans Cooling for rework. They disassembled it, ceramic coated the housing, cut off the bypass inlet, tapped the opening installed a bleeder fitting(I don't use the bypass inlet in my setup), drilled a small hole between the inlet cavity and the impeller cavity for self air bleeding to prevent cavitation, reassembled the pump using double roller bearings and a cast high flow impeller. I installed a smaller diameter double pulley to increase the pump rotational speed and volume.
On my cooling setup, I added a 2nd coolant outlet port to the left (drivers) rear of my performer intake. I route the coolant from both rear intake outlets to an adapter under my waterneck. The waterneck bypass outlet is routed to the heatercore and back to the heater return inlet of the waterpump. I wanted to balance the coolant flow through the heads and get more heat out of the rear head areas. I have a mechanical temp gauge installed in a tee at the right rear intake outlet cause thats the hot spot. This is where my past problems have occurred, mainly on #8 but also on #5 & 7 cylinders. I also use Evans NPG coolant with no water and have a Griffin crossflow radiator with dual electric cooling fans. The Evans NPG has a vapor/boiling point of 370 degF. It doesn't dissipate heat as well as water and that is why many people won't use it. However, it has four advantages over water: 1.Much higher boiling point which helps prevent vapor pockets within the water jacket of the heads/block. 2.It operates at a much lower system pressure - I use a 7 lb cap. 3. No water so no corrosion/electrolysis and resulting deterioration of the cooling system components. 4. It doesn't need to be changed. Number 1 is the biggest concern to me as I have had engine damage as a result of water/coolant boiling in the heads, forming vapor pockets and setting up a chain of events resulting in piston damage before I realized there was a serious problem. The stock temp sender is in the front of the intake and doesn't necessarily reflect what is happening in the rear area of the engine. Probably more info than you wanted, sorry for going too far if you weren't interested.
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Old 08-27-2002, 05:15 AM
Chero77 Chero77 is offline
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My experience with Smog has been similer to Wesdogs. What really matters is the tailpipe numbers. When it comes to the visual test, the Smog Shops give you a lot of leeway. You have to have EGR, PCV, air injection, and the factory air cleaner. As long as you have those items and you pass the tailpipe test you will probably pass.

One advantage we have is that nobody knows what was stock on a 25 year old AMC. If you swap a stock 4350 for a Holley, the smog guy will probably just assume the Holley was stock. All the computer tells him is that 401s came with four barrels. You could probably even get away with an Edelbrock/Carter. Just tell the smog guy, the orignal was a 4350. They are no longer made and yours couldn't be rebuilt. The Edelbrock (1406) has all the smog hookups the stock carb had. If you pass the tailpipe test, he will probably pass you. Bear in mind that many/most of these guys are "car guys." You come in with a decent 25 year old car and most oftent they will go out of their way to make you pass.
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Old 08-28-2002, 09:42 AM
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Started the Indy head installation process yesterday with the disassembly of the heads. Found lots of small filings/chips inside. Indy didn't do a very good job of cleaning them before installing valves and springs. Anyone who gets a head kit should be sure to clean them real good.
I am also going to proceed with a MPI conversion as part of the head installation since the engine will be out of the vehicle. Took my Holley Street Dominator over to the shop to start the modification process to add injectors. Decided to use it rather than a Torker. I got the Dominator from Ralph and after closely comparing the 2 manifolds I am convinced he is correct that the Holley Dominator is the best manifold choice for a FSJ MPI conversion. It does have small intake ports at the intake to head interface. The runners start out at about 1"x 2" in the plenum. They decrease to 1"x 1" at the interface to the head. This will provide lots of air velocity at the head intake port. This 1"x 1" opening seems small but is probably fine for the FSJ application due to the lower rpm range that is actually used: 0-5500. The intake port could be opened up a bit so I will be doing some porting to increase the flow capacity. This is a single plane manifold with a divided plenum. I may remove the divider. It has a lower profile than my current Performer manifold so it won't cause any clearance problems with the hood like the Torker would. The intake will sit a half inch higher with the Indy heads so the lower Dominator profile helps cancel that out. Sure wish Edelbrock would market an intake manifold that supports an EFI conversion!
I will be plumbing in exhaust gas from the headers to the choke heater cover to allow the EGR to function in the future. There are no exhaust bypass passages on the Indy heads so no EGR exhaust source is available for the EGR plenum area. Will be using an Accel 1000cfm throttle body with TPS and IAC. Going to use a F.A.S.T. ECU with wideband O2 for ignition and fuel injection control. I also visited TPIguy's website http://www.customefis.com/ today for the 1st time in about a year and he's got lots of good stuff on there. Didn't see it listed under any of the IFSJA links.

[ August 30, 2002, 09:32 PM: Message edited by: Wesdog ]
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  #13  
Old 08-28-2002, 10:35 AM
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well dude, it sounds like you have a few problems, one is the fact you live in P.R.O.C. the other is that you have a 360 which wasn't built to take high hp numbers at all. the main webs are half the thickness as a 401 and the crank and con rods are cast iron and not nearly as strong as a 401's. the other problem is the overheating one, with your power needs/wants, your going to be overheating more with that smogged 360. sorry, man but facts is facts. if you want power with lower heat, buy a chevy engine and build it up, your throwing good money after bad here. Now a 401 was built to make power and run cooler, but WITHOUT SMOG ****! the problem in the overheating is simply this: you have too much timing advance for your fuel/air mixture or your cam is not set up (timed) to the crank properly. period. Ive run a 401 for 4 years now with 9.5:1 compression, edelbrock performer cam, intake, (and recently 1405 carb) it has the stock 1.6:1 rockers and of course hydraulic lifters and such. pocket porting and head milling was done and I have no aftermarket ignition system components, the stock motorcraft E.I.C. module and distributor is used. the thing that keeps it from pinging at 4500 ft elevation though, is slightly rich mixture, initial timing set at 16* and no vac advance AND 91 octane gas. this is a MILD performance rebuild set up for better than stock power and especially low end torque. If I haven't pissed you off yet , let me make some suggestions- find a 401, build it to make decent torque, swap in 3.73:1 gears and go with it. mine is pretty torquey, but I fear Mr. Performance-engine-builder who reworked the already used heads didn't check the valve seats for hardness when he charged me out the *** for the machine work and assembly on them 4 years ago, so I have a jumpy vac gauge needle and what I think is lower than what I should have vaccum all the way around. oh well, next rebuild I'll put new heads on it, done by a good shop. Yes, I have eliminated all other sources of vacuum leaks, it has to be heads, problem is- I can't find any smoking or blow-by problems! just jittery vacuum and the impossibillity to hold the vac needle at 14 to 15" at 800rpm idle.

ANY way- if you keep the 360, get some decent smog legal headers(if you don't have them) and try roller rockers and lifters. also try enrichening your fuel/air mix and/or retarding your timing somewhat. if it is like most smog-era amc v8 timing curves you'll have like 41* advance at like 3000 rpm or something ridiculous like that, you might try running with the vac advance plugged off and just going with initial and mechanical for a few days and see if your myriad temp gauges change. hope I wasn't to blunt for you, and I hope this helps.
Matt W.
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Old 08-28-2002, 01:19 PM
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Matt,
Thanks for all the info (I think?). I don't have a 360 and never have in the 22 years I've owned my Chief - maybe you were responding to one of the others on this topic? I've run this vehicle up and down the Baja deserts since I bought it in 1980 and it has performed well in extremely hot conditions with lots of gear loading it down. I've also been through a couple rebuilds over the past 230K miles due to various problems. I now approach things with the thought of reliability and redundancy in mind, not just performance. For instance, I will be able to swap my carb back on in place of my throttle body and still run if problems with the multiport fuel injection system should occur at an inopportune time. That includes being able to change the fuel pressure to use the carb. The same thing goes for my ignition system. I can run it 3 different ways with simple swaps. I hate getting stuck in the middle of nowhere like probably everyone else on this list. I haven't ever been completely stranded yet with my Chief and I don't intend on having a first time if I can prevent it. Enough of that.
I am considering the gear change you mentioned, from 3.54 to 3.73, but I will wait until after I finish the current engine work to decide. I don't currently have any over heating problems and I have curved my distributor. Haven't got it on a dyno yet to optimize it cause I wanted to do that after this round of engine rework.
I'm not ready to change pistons or mill the heads for higher compression at this time and I want to be able to use 87 octane fuel when I'm done. With my current cooling system mods, the modern Indy head heart shaped/high quench chamber design and a closed loop MPI system with timing control and knock detection, I should be able to run the engine with more advance and get better performance with regular gas. I have a Chevy LT1 in my 95 B-Body and am building a Hot Cammed LT4 to drop in it this winter. I agree that the Chevy motors are good. I also think the AMC V8 can be a reliable higher performance engine with the right parts and setup. I agree the stock AMC heads can be made to flow better and produce high horsepower/torque with the right cam and pistons. But they will never match the chamber characteristics of the Indy heads and I'm not talking just flow. The main reasons the LT1 engine can run 10:1 compression using 87 octane fuel is the combustion chamber design, reverse cooled block configuration and of course computer controlled ignition and multiport sequential fuel injection. I can't easily reverse cool the 401 (although it can be done) but I can do some of the other things that make it possible to run higher compression using lower octane fuel without getting into serious problems with pre-ignition. I will look into raising the compression in the future when I have everything dialed in.
On the smog equipment - I think I have some personal responsibility to try and keep the pollution controls intact and minimize my vehicle's contribution to poisoning the environment we all have to live in - just my personal view on the subject, to each his own.
On your jittery vacuum gauge signal - I assume you are using a manifold vacuum source that is above the divided Performer plenum for your reading? If not, you will always see a jittery vacuum reading due to the 2 plane manifold design. If you haven't already done so, see if your carb has a manifold vacuum port that is common to both sides of the plenum (not ported vacuum)and connect your vacuum gauge there. Also eliminate any other connections to that port for testing the vacuum. If you've already tried that then your diagnosis is probably correct.
Thanks for the post and recommendations!
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Old 08-28-2002, 03:09 PM
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Matt,

BTW, according to the shop manual the stock 360/401 advance curve for a 76 with automatic is 19.6 to 27.6 degrees total advance @ 2000 rpm. That seems to reflect 3-7 initial, 10.2-14.2 mechanical(@3k?) and 6.5-8.5 (12.7in max)vacuum. Don't know where the 41 degs you mentioned comes from and I agree it seems excessive. I run about 28-30 deg total right now, I haven't optimized it yet. My mechanic would like to see around 34 total with my cam. I'm not certain right now what the MPI computer controlled ignition timing tables use at the moment - I seem to recall 36 max but it is adjustable by editing the timing tables.
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Old 08-30-2002, 08:42 AM
reddog reddog is offline
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Thanks for the info WD. It was NOT more than I wanted to know. Sounds like you should have a strong REALIABLE 401. Kudos for respecting the environment as well.

Kerry
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Old 09-02-2002, 07:33 AM
Jerk
 
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Quote:
Originally posted by Wesdog:
Matt,

BTW, according to the shop manual the stock 360/401 advance curve for a 76 with automatic is 19.6 to 27.6 degrees total advance @ 2000 rpm. That seems to reflect 3-7 initial, 10.2-14.2 mechanical(@3k?) and 6.5-8.5 (12.7in max)vacuum. Don't know where the 41 degs you mentioned comes from and I agree it seems excessive. I run about 28-30 deg total right now, I haven't optimized it yet. My mechanic would like to see around 34 total with my cam. I'm not certain right now what the MPI computer controlled ignition timing tables use at the moment - I seem to recall 36 max but it is adjustable by editing the timing tables.
my 79 manual says 6 to 10 degrees initial, 14 to 19 degrees mech and 21 to 27 degrees from the vacuum diaphragm between 14" and 11" of vac. however the manual also says 27.5 to 37.o total at 2000 rpm. add it up and it ain't the same numbers. I used a dial in timing light and kept vacuum hooked up and at 3000 rpm on the ol' suntune tach, the gun said 41* advance. my perf cam says I need to run about 10 to 14* MORE than factory advance in order to get maximum potential from the cam, etc. so I pulled the vac advance turned the initial to 16* and run the mech only, and it doesn't ping now at 3000 to 4000 rpm! happy me! my total is around 31 to 34 or so.
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