Darin and his crew built my B16A1 and did a great job. Makes plenty of power and great reliability. Will continue to use this shop for all my performance needs.

Ive had a few engines and sets of heads done with these guys. The level of craftsmanship is superb, however this is a small operation. Sometimes they get a bit backed up with all of their orders, leading to a longer projected completion date. Top notch customer service.

Darin has built two of my 2.0L 4G63 engines and the quality is fantastic. One engine lasted almost 20k miles with close to 40 PSI of boost as a weekend warrior. The second one will be the same boost pressure but a larger turbo. They made a few mistakes but every time I addressed it, they corrected with little to no hesitation and guarantee their work! Thank you so much Darin and team.

I had a Oldsmobile 455 built for my 1953 Olds 98. All the machine work and assembly was done by AMS and am very happy with the performance. I will choose AMS for my next build.

Had some BMW and LS engines done by them. Always a great price and service. They do have a wait time but a machine shop thats not booked out is a machine shop not worth going to.

I have used AMS for years for all of my Machine work. I own an automotive shop in town. Darin and is crew are awesome. They have helped me out so much through out the years. If there is ever an issue they stand behind their work. This is a place you can count on. see the photo to see some of the latest work I have had done.

Great service! Needed cylinder measured on tight deadline and they turned it around almost immediately. Would recommend.

Waist of time and money. Poor workmanship and flat refuse to admit their failure. I build engines for a living and they dont even stand behind any work performed.

Friendly helpful and knowledgeable. Had them set up some heads polish a crank and hone a block. Will use them again in the future. If you have a question they will find the right answer to help you out.

DO NOT USE THIS SHOP! I do not typically leave reviews but my experience with this shop was so HORRIBLE, I wouldn’t like anyone else to have my same experience. I took my 228 out of my 1950 GMC up to these guys for a rebuild.Attempt #1: After a couple of months after I dropped l my engine off, it was ready for pickup. Got the engine back and reinstalled in my truck. First startup I could hear a faint knocking noise. Drove it 8 miles and it sounded like a rod was going to come through the block. Towed it back to my shop, and pulled the oil pan off. #6 cylinder rod bearing was toast. The rod was blue and a pile of bearing material lay in the pan underneath it. Called AMS, and immediately they tried to blame me for not priming the engine, but they agreed to redo it free of charge.Attempt #2: After I dropped the engine off for a second time, they got on it quickly and it was ready for pickup a couple weeks later. Got the engine back to the shop and looked over the work done. Right off the bat I noticed that the same rod and rod cap were still installed on #6 cylinder. They were still blue in color from the previous failure but they did put all new bearings in it so I assumed they double checked everything. I reinstalled the engine and started it up and everything seemed good. However, after the initial test drive I parked it and oil was dumping out of the rear main seal, and then the all too familiar knock noise returned. This being the second time my engine wasn’t rebuilt properly, I called up in frustration.The owner said pull it out and I’ll make it right with you. After 2 botched rebuild attempts I was done giving them another chance. I paid close to $3000 for the rebuild and I just wanted my money back. I was only refunded $1200 which wasn’t fair to begin with but I accepted it because that’s what they offered. The owner claimed they had $1700 in parts on the rebuild and all should be reusable still. This refund didn’t take into consideration the $150 tow bill I had from the first failure, or the many hours in time I spent pulling and installing the motor twice.Fast forward to now, I had another shop go through it and determine what happened. The shop found bad scoring on a few of the main bearings and improper clearances (cause of the knock) and the rear main seal installed improperly. On top of that the crankshaft was ruined. (Between the clearance issue and turning it multiple times.) The crankshaft cost me $1000 alone as they are hard to come by.So all in all, I paid AMS $3000. Got $1200 back from them, then had to spend $1000 on a new crankshaft, and $2500+ at another shop to make the engine right. SAVE YOURSELF THE HEADACHE AND GO ELSEWHERE. I understand mistakes happen, but in my opinion you don’t get unlimited tries to rebuild an engine at the customers expense. Thoroughly displeased and would not recommend this shop to anyone!!!!

Dishonest and rude. Take your business elsewhere.

Our repair shop (Performance Tune Auto Repair) has used AMS Automotive Machine Supply as our primary machine shop for years, and have always received great customer service! Darin and Bob are fantastic; they take the time to listen to our needs and then they take care of us. One time we had an issue with work completed and they did everything in their power to make it right, as fast as they could (hey, stuff happens). Highly recommended!

These guys are thorough and do a great job and their shop has the capability to do anything you need including small motor work. They are all very friendly and helpful people. Highly recommended.

I brought a 1947 L-134 engine (CJ2A Jeep) to AMS since it hadnt been run for over 35 years. The block needed 4 sleeves as the cylinders had been bored out 0.080 over. We had a couple issues with the block when we started it up but Darin worked with us and he never gave up. Together we brainstormed the problems and Darin got us up and running. I have never had a business go above and beyond in solving the problem like AMS did. I would recommend Darin and his crew to anyone who wants great service and a get it done attitude. Ron BensonUpdate 3 mos later:Unfortunately, despite Darins (the owner) best efforts, the block did not survive the start up process. The thin walls (previously bored 0.080 over) failed and we both agreed the block was too unstable. Darin then began a search of his friends in the Jeep community to find a replacement block. After checking 3 blocks, Darin found a suitable block and prepped the block for 0.040 over pistons, B & H the cylinders, replaced valve guides, and decked the block. The block is now back in the our 47 CJ2 and we are going through break in procedures. No block problems and all thanks to the diligence of Darin and his crew at AMS. I am very pleased with the efforts, attitude, and final result of this shop. These guys are Awesome!! Ron Benson

Hands down the best experience with a machine shop Ive ever had. Working with with Bob and Darin has been great, they are very personable and really take pride in what they do. Finding a shop with this level of experience that can take the time to help out the little guy, is rare. Ive had a handful of engines built through them, and you really cant beat the quality or the service. Theres no guessing games ever, they just have the right answers when it comes to anything automotive machine work. Pride is an endangered species in todays world, so when you find a group that has it, stick with them.....I will.

Was pleasantly surprised with the great attitudes, and skilled workmanship of these guys. Brought an old 304 in that was rusted tight. They broke it open and fully rebuilt it. I will be back for years to come.

Darin and the guys at A.M.S. are always top notch. My friends and family have used them several times. Always happy. Also used them for hundreds of times as my go to machine shop in the auto motive industry for the last 15 years. Things happen. But they always make it right. Thanks guys.

Stuffing more nitrous than I should through my AMS built 408w and it loves it. Great team to work with. Highly recommended

I think this place is under new ownership because its nothing like it used to be, they tell you two weeks to get you in the door and months later you finally get the phone call with an astronamicle price ! Im 1,750 dollars out of the door on a big block Chevy thats crazy to me, Ive been building engines and drive train components for 25 years . I can have a head and block on a 3306 Caterpillar done for that price and thats doing the counter bores.

Took my tiburons v6 there to get decked honed and have the bottom end assembled as well as having the heads decked and both head gaskets were leaking because of scratches in the block when everything was back together. Thanks for wasting well over $1500 and 3 weeks of my time

These guys are the best there is! I cant recommend their work high enough...and we would never even consider taking our engines anywhere else. Thank you AMS for outstanding service and exceptional workmanship.

In a day and age where its hard to find an accountable machine shop AMS is where the search stops. They have taken care of us at Auto Doctor and have earned my business on my personal performance needs.

It is interesting to see several positive reviews of this company but this is not the case for us. About six months ago we called AMS about possibly rebuilding a Buick 350 V8. This engine was originally a high performance, high compression engine, but had been installed in a Jeep. It was completely stock. We discussed with them the idea of lowering the compression and installing Fitch fuel injection to make it run better on the crummy fuel we have today. They said that this could be done and it would take three to four weeks, and cost between $3000 and $4000. It took over four months and cost around $5000. My husband is a former farmer, mechanic, and classic car collector. He has rebuilt several small to medium engines over the years, and used to race 4 wheel drives with all the work, skill and knowledge that this requires. His father was an automotive engineer and taught him the basics of engine design when he was a teenager. When we have purchased engine parts for rebuilding in the past from reputable firms, there was no worry about whether they were balanced or not as they were made for the specific engine. A silly argument developed between my husband and the manager over whether the engine should be balanced or not which is an extra charge option. It seems to us that if they were concerned enough about this that they should have recommended this at the beginning and we would have OKed it. But they did not balance the engine and it vibrated badly when it was installed on the dyno. They had installed a set of chrome rocker covers even though we had supplied a set when we delivered the engine and tried to charge us for them. Amazingly enough, they could not find an adapter to install the Fitch on the engine and my husband had to locate one and send it to them. They had to tear the engine down and reassemble it and then tried to charge extra for something that we regard as their mistake. When it was reassembled, it ran smoother, but was painted the wrong color and had to be repainted. A friend of ours has reinstalled the engine in the Jeep, however my husband and I have been on a several weeks long business trip and have not yet had a chance to drive it on the highway to see if it runs correctly. The people at AMS had been informed of our schedules at the beginning. We feel that we have lost all use of this vehicle for this year due primarily to their incompetence and lack of a customer service attitude, and we cannot in anyway recommend them.

Fantastic shop. Highly recommend this shop and the people that run it. They will stand behind there product 110%. Worth the drive from Greeley every time.

The AMS crew has done a great job with all my race engines. Thanks for all your great work.

Darin and his guys bored and rebuilt the lower half of the motor for my 78 f150, they explained different options, etc. on ways to gain HP and any costs associated with it. Super happy and will be taking my next motor there for sure, thank you!

After assembling a short block they claimed was zero decked, they assembled the top end. after they finished it I told them I wanted to have it dynoed and they claimed they would dyno it but only make a couple of pulls for a whopping $650 I got to watch them hammer the ends off of my pushrods, act like it was the pushrods fault ( ALL 16 )and like it wasn’t a big deal there was metal shavings in the oil from the pushrods. “There is no metal in that engine and there is no reason to take it apart.” The valves were floating at 5000 rpms and hammered the valve seats pretty good. Not one valve was sealing upon disassembly👌🏻 Which by the way they refused to admit any wrong doing or fix it so I had to resort to taking the assembled pile of junk to another shop to be documented, in which we found all the bearings were completely destroyed throughout the bottom end. My “zero deck” stroker that was supposed to be 11.6:1 was only 9.6:1 and had the piston .030” down in the bore (basically a mile). They told me that my compression ratio was exactly what I wanted and it was 11.6:1, and that there was something wrong with the trend pushrods. They also installed non chamfered rod bearings on my 4340 crank that were destroyed from the extra large crank journals... but they managed to install the correct chamfered bearings in the crank main journals? They lied to my face about the installed height of my springs and the seat pressure. Showing the height mic already rigged up when I got there they measured my springs at 140 lbs on the seat. After telling them pull it off the dyno and they weren’t allowed to work on it anymore, somehow all the spring pressures dropped to 114 lbs on the seat taking it all apart. Hmmmm odd.... I had a 7000 rpm cam installed that ended up never making it above 5350 rpms. The port match work on my intake was so bad there is actually Humps in the wall of the runners... horrible turbulent flow. Looks like it was ported with a weed wacker. Among all of these reasons to never darken their door again, I asked for ferrea 6000 valves specifically, only to find after assembling the engine they bought garbage knockoff ferrea valves ... engine pro 2000 series!!! JUNK! When confronted they said “that’s just what we do. You don’t need ferrea 6000 valves.” I couldn’t believe my ears. Someone telling me what I both wanted and needed after asking for something already. All of this being said, the engine machine shop that took my engine apart and documented the work found $7k worth of labor and parts needed. It turned out they never zero decked my block they never align honed the mains, they installed the oil pump driveshaft upside down, my brand new heads were never milled as I asked and they said they would do, they used a head gasket almost 2 times as thick as the one i ordered, because it “didn’t exist” this gasket is still available today, they just don’t know what they are doing. SAVE YOUR HARD EARNED MONEY AND TAKE YOUR PARTS ELSEWHERE! THIS SHOP DESTROYED JUST ABOUT EVERYTHING INSIDE MY ENGINE EXCEPT THE CRANK RODS AND PISTONS. THEY REFUSED TO FIX ANYTHING OR REFUND ANY OF MY MONEY BACK. I AM OVER 11k IN WITH MEETING WITH AN ATTORNEY. HAVING THE WORK I ASKED TO BE DONE SOMEWHERE ELSE WITH SOMEONE WITH SOME DECENCY IS GOING TO COST ME ANOTHER $7k TO GET THE ENGINE I ASKED FOR ORIGINALLY. THE OWNER REFUSED TO ADMIT ANY WRONG DOING BUT ITS PRETTY AMAZING THAT HE COULD STAND THERE AND LOOK ME IN THE EYES AFTER FINDING JUST HOW BADLY ASSEMBLED THIS ENGINE REALLY WAS. THE CRANK MAIN STUDS NEVER GOT ANY LUBE GOING IN AND BARELY CAME OUT OF THE BLOCK, OH AND THEY TOLD ME THEY MEASURED THE LIFT AT THE VALVE WITHIN .001” OF THE CAM CARD WITH A HYDRAULIC LIFTER IN THE BLOCK AND AT THE SAME TIME ADMITTED TO USING THE WRONG ROCKER ARM RATIO TO CALCULATE THE PROPER LIFT. HE CLAIMED HE GOT .567” on a .568” cam but the .568” was measured with a 1.7 rocker... my rockers are 1.72 at the cam should have been .574”. Talk about putting your foot in your mouth. ONE WORD FOR AMS- CROOKS

Guys are the best in the business. Tried other shops, dissapointed. Dont bother with any other guys, just use AMS. Not only is their work top notch, their prices are fair, and if you ask around to people who use these guys and you will find they dont screw around. Shop is surgical clean, and they are the shops that other peole use to fix other machine shops messes. Worth the drive from anywhere.

Absolutely awesome workmanship. The guys at AMS take pride in their work and it shows.

Bob and his crew do great work at a great price. I have taken them three different motors and all the work has been exceptional.

DO NOT USE THIS PLACE!!!!!!! Where to start. lost work order for two weeks, I went in to check on it and thats when they said O youre the one with the (eng.). 2 weeks later was called and told parts ready. but not the block. why not the block? well AMS asks me do you have (parts they lost)it in the parts we gave you? well AMS lost the timing gear, cam gear, crank gear and balance shaft gear. not to mention I wanted the parts hot tanked (cleaned up gasket sufaces) rust, grease and such. Just power washed I can go on but Ill end it here I have pictures to back it up. DO NOT USE THIS PLACE!!!!!DO NOT USE THIS PLACE

By far there work is great. But I took my crankshaft to there recomended place THEY USE and it dfailed after 300 miles take your crankshaft work to a good place not western engine. Ever get the hole in your chest feeling after youve spent thousands?

Did a great job on my heads! Couldnt have asked for more

AMS is awesome the owners are great everybody that works for them is awesome me a 383 stroker motor for my 70 Chevy pickup runs beautiful would not go anywhere else!!!

These guys are the best!!! Wouldnt trust anybody else for all your machine work.

AMS has taken care of all of our cylinder heads and other machine work. When reading some of the negative reviews keep in mind a lot of these issues are installer errors by amateurs.

No communication was told a a week and a half on short block three and a half weeks later block was just bored, freeze plugs installed (steel),cam bearings installed before block was clearanced for stroker crank not very smart to clearance a block with fresh cam bearings and it was a marine application where brass freeze plugs should have been used took block to us automotive and machine 4 days later completely assembled

Very good machine shop. Great people.

They are a great engine building shop, I will continue to bring them engines to work on. The staff is very knowlegdeable and curtious.

Great group of guys! True Craftsman!

Great work from great guys.