Trends UK Haynes Build Your Own V8 Engine

Overall, we loved this very well engineered model. We did run into a few problems though. First, the crankshaft was sloppily molded in one section where 2 of the piston connecting rods are supposed to attach (step 2). It’s supposed to be a circle but, since each each half was slightly offset, it ending up being a bit too wide. Also (and for the same reason), it had ridges that preventing smooth rotation of the connecting rod around the crankshaft (see photo). I was able to sand it down with a small file to get it to work. Second, there were 3 instances where screw holes had to be created or widened. If there was no hole, I very carefully started a hole (really just a mark in the plastic) with a small nail then used a small wood screw to widen it. I was worried that the plastic would fracture but it didn’t. I was very gentle. Third, the left distributor (for cylinders 5-8) was quite difficult to place onto the camshaft (step 26). The camshaft is not perfectly circular but deliberately has one side that’s flat as does the hole in the distributor. They were not easy to match but a lot of jiggling and persistence finally won the day. Fourth, during the timing step (step 27), the distributors have to be turned clockwise in order to illuminate the correct “spark plug” (LED light) but even when the right-handed distributor (for cylinders (1-4) was turned as far rightward as the screw slot allowed, it still didn’t light up the correct LED. It turns out that the screw slots had to be turned just a hair past the screw posts in order to light up the correct LED (#4) but that would mean the distributor couldn’t be screwed in place (it’ll make sense when you get to that step). To fix this, I widened the left side of the screw slot with a small file so it could turn just a wee bit more to the right. That was just enough to work. Another fix is to swap the right and left distributors (see the excellent review by Jerry Davis) but I didn’t want to remove them as I had trouble getting the left one on in the first place. Finally, it should be noted that newer version of the model has 2 additional plastic posts on the front of cylinder block on either side of the crankshaft (at about 4 and 8 o’clock) to help keep the timing belt from falling off. I only mention it because it was a little confusing that our cylinder block didn’t quite match the diagram in the manual.A few tips: I was worried that my smaller than average 8 year old daughter wouldn’t be able to screw in the pieces since several reviewers said it was difficult. However, she didn’t have too many problems in that regard. It comes with a a very small Phillips head screwdriver that worked fine. Ours didn’t come magnetized but that’s ok. Some people prefer it that way. We did, however, magnetize the screwdriver with a magnet which I think helped. We also used an accessory screwdriver with a wider handle (whenever we could) to make it easier to turn. We also purchased a cheap modelers tool kit (Rustark 10Pcs Model Tools Craft Set Modeler Building Kit) for about $10 that came in handy, especially the file, the small knife, and the side cutter (for cutting the pieces away from the plastic frame). Just be patient, read the directions very carefully, read some tips in the amazon reviews (Jerry Davis, A. Aurelius, etc) and be prepared to modify a few pieces. Summary: The educational value is through the roof and it was a ton of fun to build. I have almost no model building, automotive, or mechanical skills to speak of but we were still able to get it done in a few hours spread out over 3 days with the timing spot on. It’s extremely detailed and teaches not just how an internal combustion engine works but about a lot of other principles of mechanical engineering like cams, gears, pistons, bearings and other stuff I can’t think of because I don’t know jack about engineering. It also teaches patience, troubleshooting, and persistence. The kit says for ages 14+ but I would guess that an interested 11-12 year old should be able to do it with minimal help. One reviewer says that her 9 year old finished it unassisted but I find that surprising (so did she to be fair). I think most 9 year olds would need at least some help. But that’s part of the fun. I LOVED building it with my daughter (who has expressed an interest in engineering). Almost forgot to mention that this latest version comes with an AR (augmented reality) feature. It’s super cool and educational. Didn’t work on my iPhone X but worked perfectly on our iPad. I would highly recommend this model for kids, teens, and adults who are interested in learning how an internal combustion engine works. My daughter enthusiastically rated it 5 stars but I’m thinking 4.5 just because I had to modify some components to get it to work. Hope this helps and have fun!!

This little engine is complete, down to the smallest detail. It even has individual cams, which have to be placed, in the right order on the camshaft. The camshaft operates the cam followers, through rockers and on to the three-piece valves, complete with springs. Even the valves are in their correct proportions with larger inlets than exhaust. Yep, it's that detailed.The kit has the usual pieces, held to a frame by tags. The frames are designed so that you use them in order to avoid getting pieces everywhere and easily lost. All pieces are numbered individually for easy identification. The tags are best removed with a sharp knife or fine sandpaper to facilitate the engine going together, and operating, smoothly.Once the engine is completed, each cylinder lights up to imitate firing. The timing is controlled by two distributors and each can be adjusted so the spark occurs before TDC. The engine is turned by a small electric motor, powered by three AA batteries, which also power the "sparks".The kit is completed without the need for any glue, as it is all held together with screws. The screwdriver provided is adequate but the very thin handle means it can be difficult for young hands to develop enough torque to screw the metal screws into plastic. The same size screwdriver with a fatter handle would be easier for small hands.This is a brilliant project for completing over several evenings with a child or grandchild. Follow the directions religiously. Knowing how to put together a real V8 is no guarantee you can put this one together without a hitch. The box says it's for fourteen years old and above. I had great fun building it with my six-year old grandson, making allowances for his shorter attention span and allowing him to determine how long the building sessions would be.The engine can be torn down and built again if need be, a number of times, which makes it great value.

This model is really cool, but be prepared for minor and possibly significant fit issues with a few pieces. We did this with a mechanically inclined 9-year old, and needed some adult help but mostly did it himself.Pros: As advertised, this is a quite detailed model engine. In particular, we liked the detail of some pieces like the cams and valves; and that it all goes together pretty much like a real engine would. Just one example -- the distributors actually fire like real ones, so you have to set the timing! And the cylinders actually follow a proper timing sequence, so the cams are really operating, etc.The instructions are very detailed (in a good way). There were only one or two places where we scratched our heads.Cons: We had some fit issues. A couple involved minor trimming of plastic pieces, no more than on any plastic kit really. But one significant one on a camshaft that just seemed too long (and/or the hole in the distributor was too tight). Was scary to get out a hammer and hacksaw, and I think we were kind of lucky not to bust a plastic piece trying to get the distributors and timing belt sprockets on the camshafts. [In case anyone else is having the same problem: We had to hammer both camshafts HARD to get them fully through the timing belt sprocket, and we did that hammering from the distributor end with sprocket partially on. And even with that, we could not get one distributor on enough to screw it on to the housing; or, it jammed the camshaft/timing belt gear too much. So we literally hacksawed off about 3-4 mm of camshaft on the distributor end. All good, and plenty of cam to fully seat in the distributor.]Overall, would love to give this 5 stars for coolness and detail, and a very nice challenge for a growing model builder. But I think the fit issues could really stump someone and absolutely require adult help. So go for it if willing to deal with fit issues.