Project Elantra: The Foundations of Power

Once again we are continuing this saga of our ragtag conesport race car that we call Project Elantra. Last time, we completed a two-parter on the car’s upgraded instrumentation, in the both of which we somehow digressed to unrelated topics of stoichiometry, cooling system upgrades and turbocharger manifolding, among others. In this update we promised to talk about the car’s engine management. In the process of doing that, however, we decided to spin that off into a separate article series called Evaluating Engine Management Systems.

We’ll instead talk to you about the powerplant, that cantankerous cast iron lump that lurks beneath the fiberglass bonnet. And why not? We’re sure many people who have seen our car run would be curious as to what we’ve done to it. Perhaps even our competitors would like to also know and compensate accordingly. But we aren’t worried. Because the top FWD drivers are still kicking our asses, even with the current sorta-powerful engine we have now. Our friend Alex Bautista is still about a second faster of us in the last legs of the 2012 Slalom season, and he has a stock Vios engine in his Echo! And faster still is Pathrick “Tatang” Bautista, last year’s FWD Slalom King with a car slightly younger than we biologically are. We can list names of people who are still way faster than us, and let’s not even get to the Starlets!

What everyone – including ourselves – has to be reminded of that it’s not the shiny bolt-on parts, or the number of atmospheres you’re stuffing to the motor, or whatever else you have done to the car that makes you win. It’s really the loose nut behind the wheel and on the driving seat. The driver, and his skill level, makes the difference. With about fourteen slalom legs within the past fourteen months on our belts, we’re starting to kinda know what we’re doing. But the other people have been at it for far longer than we have. Kaya, madami pang palay na aanihin, madami pang bigas na isasaing, madami pang kanin na kakainin.

Read on for the engine stuff after the jump.

Yes, Virginia, it’s still a Hyundai engine

Every race weekend, Project Elantra’s hood gets propped up as the Kuhol.net Automotive Racing Team (K.A.R.T) figures out how best to make the car run properly. The engine setup is by no means a beacon of reliability. Thus, our race participation over the four legs where we didn’t race a spare car almost seem to merely be venues for troubleshooting our car’s woes.

With the hood open, curious onlookers, competitors, and sometimes even the organizers can’t help but go to our pit garage, an overstatement on what is basically a ramshackle tent, and take a gander at the car’s engine bay. And the first thing they say is an unequivocal, “Wow, is that still a Hyundai engine?”

Yes, it still is. Well, it isn’t the engine that originally came with the car. That would be the engine that’s now lying somewhere in the garage, a 1599cc Beta 1 G4GR engine. Pumping out a grossly optimistic 116hp figure, the G4GR is only notable for motorsports use in the  MP Turbo racing Elantras back in the late 90’s. We were told by an engine builder that these engines can rev safely to 8300rpm (the stock fuel cut is at 6800-7000rpm). But this engine model is quite rare worldwide, and not many other people have done work with the motor. There isn’t much in the way of open-source knowledge and upgrade parts availability as far as the G4GR is concerned.

We swapped in the 2.0 version, the 1975cc Beta 1 G4GF. This engine was fitted in Hyundai’s most sporting offer at the time, the Coupe/Tiburon/Turbulence. This motor and its newer version, the Beta 2 G4GC, is found in several Hyundai and Kia models, such as the Tucson, Soul, Tuscani, Sportage, and several others. Given it’s ubiquity, the knowledge base to make this engine make more power is there, and there are off-the-shelf performance parts available from Korea and the USA.

From Seoul to San Francisco, tuners have made some decent power figures with the 2.0 Beta, but mostly via turbocharging. Due to its basic design, such as having an undersquare bore/stroke ratio, slave-driven DOHC setup, and overweight reciprocating parts, going “all motor” isn’t the best way to produce the power that most people want. One can go N/A, but the parts spend and engine building costs may be too much, especially for a guy in the Philippines. But if you really want to go this route, for starters you’d want to get high-comp pistons, the lightest set of con rods you can possibly afford, camshafts with ridiculous lobe profiles, dual valve springs, head ported and polished, and have the whole lot balanced, blueprinted, and assembled by the best engine builders in the business. This route would probably get you about 170-180WHP?

Most people fit a turbo to the 2.0 Beta. With a decent sized scroll, 200WHP isn’t too hard to get with stock internals and low boost. Koreans are known to rock 350whp on the streets with only low-comp pistons as an internal mod. To put that into perspective, 350whp on a turbo B-series requires modifications to the engine block as well as a piston/rod change. A fully-built Beta engine can pump upwards of 600hp, and that’s with the OEM crankshaft and block. The robustness of this powerplant aren’t surprising if you knew that the Koreans were, *ahem*, “inspired” by the excellent 4G63 of their long-time technical partner Mitsubishi. That’s not to say that the Beta is a 4G63 in Korean drag, as there  are merely a few similarities between the two designs. Those few similarities, however, are quite significant for the tuner, as some sundry components can work, easing the task of finding and paying for speed parts.

The 1.8 Beta Piston/Rods Mod

Now that you know that the 2.0 Beta is not so bad a starting platform for boosted power, it also wouldn’t surprise you that, internally, we haven’t done much to the engine. We haven’t even had the motor assembled by a race engine builder –  just ourselves and a few specialized tools like a torque wrench and an angle gauge to torque the head on properly. We didn’t even remove the block from the car while doing the proceeding work!

The stock pistons don’t last beyond the 250whp level. We should know. The turbo was fitted way before we lowered the compression ratio. When we opened the engine up to do so, we saw cylinder #4 with three cracks and a depression due to tope or detonation. It was a stroke of luck that we were changing the parts at that time, otherwise if left alone our engine would have been toast.

Our power goal was in the region of 300whp, which would not have been possible with stock internals. Simply changing pistons to low-compression units would make the engine good until 400hp, wherein the connecting rods become the weak point. Imagine that, 400hp capability with only a piston change. In a Korean engine.

Turbo pistons aren’t cheap. If we bought a set of US branded slugs from abroad, they would at the very least be about $600, exclusive of shipping and customs duties. We instead did what the Koreans do, by installing 1.8 Beta (G4GM) pistons and con rods to their 2.0 Betas.

By fitting pistons and con rods from the 1.8 Beta, the C/R becomes a very-low 7.7-7.8:1. This is achieved by the 1.8L’s 5mm shorter con rod and the 1.8L’s higher piston dome. The resulting C/R is lower than the de rigueur 8.5:1 ratio of the in-stock turbo piston sets, and lower than our ECU tuner’s recommendation of 9:1. Concerns with this setup were valid, because with too low a C/R, the engine is less efficient in producing power. The result is elevated boost threshold levels (meaning, longer turbo lag) and reduced ultimate power output, among others.

But an OEM 1.8L piston set is cheap, us acquiring the set from a shop in Quezon City for around a quarter of the price for branded turbo pistons from the USA. The con rods for us were free, as the 1.6L and the 1.8L Beta use the same con rod, and so we simply pulled the set from our old engine. While reassembling the engine, we tried to compensate for the very low C/R by fitting the head gasket from a newer model 2.0 Beta 2 (G4GC). The Beta 2’s head gasket is slightly thinner than the Beta 1’s (2-layer vs. 3-layer). Even just by a smidgen, we hope that it would bring the C/R up closer to 8.0:1.

We torqued everything to factory spec, most especially the head bolts. The Beta has an interesting torquing spec for its cylinder head, at least to us novitiates in engine rebuilding. You torque each head bolt to an initial torque, and then you torque them two more times, but torquing them to a specific degree of rotation. In order to not mess the rebuild up, we had to buy a angle gauge tool to make sure we twisted the handle just the right amount.

And that’s it for the engine internals. There are no other tricks. By only using OEM components, our engine is capable of producing close to an unnaturally-aspirated 400hp. Yes, it’s not the best solution, but for the price and considering our power goals, we’ll accept the slightly more laggy turbo spool anytime. Plus, the parts bill to get this capability from your G4GF is only about Php 15,000 or less. Seriously, why don’t more people tune Elantras?

Next Time

There’s more to the engine bay than 1500 words can stuff in. We will continuing this installment with the turbo setup, drivetrain mods, and other relevant baubles. Stay tuned, and keep it slow!