The S7 is a pretty nice engine. Although I usually ran Worlds when I was running the RBs, I do have a lot of experience with the S7. The life on them is pretty good, if you treat it right. The one we've been running has about 7 gallons on it and we haven't done anything to it. As a test, we've been running this one on Blue Thunder. We ran the last one on 30% White Lightning and although we got good power, the bearings went out on the 5th gallon of fuel. I don't know if it was just its time or if the fuel had something to do with it.

Anyway, the S7 is a good budget engine. It does't have much bottom, relatively speaking. I can tune an RG to deliver more bottom than the S7 has, without killing the RG. The S7 doesn't have as much top end as I like either. My stock P5X will out run the S7 we've been running.

If all you are worried about is the life of the engine and better than fair performance, the S7 may just be what you're looking for. It's a good medium track engine. If you are running a tight track, I think I'd suggest the S5. It has a better bottom, at the expense of a bit of the top end.

I hope I'm not sounding as though I'm knocking the S7, because I'm not. It is a good engine that performs reasonably well. I think that the best way to characterize the S7 is to say that it is smooth. I find it really hard to get myself into trouble when driving an S7.

The greatest problem with choosing an engine according to price is that there seems to be a gap between the $110 RGs and Thunder Tigers and the $300 RB Worlds and P5Xs. There is very little in between. Off of the top of my head, the RBs would come first, then I'd have to mention the Sportwerks .21. Its a good engine that can be had for about $180. It too is reasonably fast and should last you at least five gallons. The SHs seem to be pretty good performers, but I can't speak as to the longevity of the engine life. There are also the STS engines. They are low priced and fair performers. In fact, I raced against two of them the weekend before last. They were the ones with the green heads. Maybe the team engines. They ran OK, but again, I can't comment about engine life.

As a final note, I want to say that I love RC. I go through about two gallons of White Lightning 30% a week. I've gone through about 13 engines in the last seven months. Actually, I haven't gone through all of them. Some are still running good, but I have killed about half of them. A couple of them were Novarossis, a couple were RBs, a pair of O.S. VG30s, a Hyper 21, and a couple of others. The life that you get out of the engine depends on how you run them. With the engines that I relegate to race duty, meaning that I only race them, have lasted a LONG time. This is because they only have to run the qualifiers and actual races and have time to cool after about 15 minutes of running. The engines that I practice with get run hard. Most times they only get breaks long enough to allow me time to change a battery or air filter. I put a half a gallon through a P5X this past Sunday without giving the engine a real break. Engines that get treated like this usually don't last long. Although they usually have compression, the bearings usually go out. Probably from all of the heat for prolonged periods of time. I've had conrods eat though crankshafts and all sorts of stuff go wrong.

I don't want to blow my own horn, but I can afford to buy a new P5X or Worlds every couple to a few weeks and it's what I've been doing. My motto is drive it like you stole it. It's what makes it fun. Some of the guys that I run with don't have the resources that I have and have asked me the same question being asked here. They are looking for a good engine that will perform well and last them a long time. My answer to all of them is the same. First, there is never a guarantee as to how long an engine will last. For the most part, any engine will last longer if you baby it, but what's the fun in that. Second, how well an engine runs depends greatly on your ability to tune. You'd be surprised at what a cheapie RG that is tuned well can do. The last thing that I tell them is that this is a hobby that's supposed to be fun. Having to worry about your engine and babying it, isn't fun. Also, having a running RG or Thunder Tiger Pro .21 is more fun than having a blown Novarossi or RB. Personally, if I were on a budget, for the price of the S7, I'd just buy two RGs or Thunder Tiger Pros. This way you can run it like you stole it and not have to worry about it. If you blow one up, stick the other in and keep running.

OK, I know I'm rambling. I don't know what got into me. On a last note, I've found the RBs to be a bit pipe sensitive. Since you are on a budget, this could be a drawback. I run my S7s and Worlds with an Ofna 086. They can be had for relatively low prices allowing for a backup. I don't know how, but my pipe always manages to get destroyed. No holds barred money races can get nasty. Some will tell you that you should put a low end pipe on the S7 to get more bottom out of it. I don't want to argue the logic behind this reasoning, but I've found that engines (especially the RBs) just seem to like some pipes more than others. I've found that is it usually better to cater to an engines strong suit rather than try to turn it into something that it isn't. The RB S7 is, I believe, an engine that can be categorized as a mid to top end engine. As such, it likes to breathe and top end pipes allow it to do this. Many also recommend 1.1 springs with aluminum clutch shoes to get more bottom. I've found that 1.1 springs are too heavy and make the buggy twitchy on tighter tracks. The aluminum clutch shoes only serve to keep things hot and destroy clutch bells. I'd recommend Mugen 1.0 springs and black shoes. They last a long time and aren't expensive. If you want a bit more of a delay before the shoes grab, just put them in backwards and try that out.

My point in all of this is that the RC hobby is a money pit. Stick with what you can afford to replace if you have to. A rebuild kit for an S7 costs more than an RG or Thunder Tiger. A friend of mine just got a Thunder Tiger in and it's a real screamer. A breeze to break in too. We're going to race it this weekend after I get some time to tune it. If it runs like I think I can get it to, I'm going to buy two or three of them instead of another P5X to use for practice.