Thread: How to build a 300 WHP/Liter SR (on the cheap?) discussion.

I've been putting this open conversation off long enough. I want to talk about building a motor as an exercise. Here's the task: you need to make 300 WHP/liter on pump gasoline and keep the engine relatively inexpensive and reliable ("look what we did with so little"). It needs to be fun and sound impressive so a high red line is a must. It doesn't have to make early horsepower (torque) but the more, the better. Pretend you're trying to come up with a parts list that anyone with a tight budget but high skill level can obtain/make. All factory Nissan parts are fair game even if not USDM. All aftermarket parts are fair game but choose wisely. Assume the builder can weld and fabricate custom pieces like brackets and manifolds. And because I get to call the shots here, let's say it's going to be a RWD engine (I know, I know) and engine bay size is a non-issue. Engine management is a given; assume adequate control. Meth/water/nitrous injection and intercooler sprayers are off limits. The only consumable allowed is gasoline.

I think first we should pick a bottom end to work with, then we can move on to head choice, then valve train and so on.

I'll give you something to start off the conversation. I'm thinking a typical RWD DET bottom end would be sufficient and the factory compression ratio of 8.5:1 is satisfactory although a RWD SR20VE+T is not out of the question. Forged pistons and rods with ARP studs sound like a good idea but the forged stuff might not be necessary. I'm thinking 9,000 rpm redline to obtain the output I'm looking for (maybe I start a CA18DET discussion later on) and keep things fun. Stroking is not part of the picture as it tends to hurt specific output. Sleeving the block can hopefully be avoided to save costs. Boring also should be avoided for the same reason and probably won't help too much with specific output (redline could still be kept high though).

I know this seems to be a turbo discussion but I put it in the General section to bring in the N/A guys as well for when we get to the choice for the head. I'd like to work with the power players on the forum here and hope that the others can enjoy the ride.

So, bottom end first including block, rotational assembly and any work/modification directly related.

I would go forged H beam rods, and forged pistons, get the crank balanced, knife edged, and possibly re-polished. EVERYTHING would have ARP hardware. I would definitely run a crank scraper and windage tray/baffled pan. I would also run about 10:1 compression, with lightweight stock diameter pullies.
There would also be a fairly large turbo, possibly a GT3582R, the head would be a P&P job with oversized valves, and worked on a flow bench until it could not flow anything more. There would be a definite need to massage the combustion chambers at that point, and it would be done. There would definitely be some high lift high duration cams, and nice stiff springs.
Intake manifold would have to be an equal length tuned sheet metal intake with a full radius trumpet, and a large throttle body, probably 85mm or so.

On the cheap? no, it won't happen that way. But man.. that thing would be nearly indestructable, and probably put out a good bit of power...

92mm pistons and the stock crank should yield 2.3l and should rev to 9k as per Andreas VE thread.

Dustin can you defend your choice of 10:1 compression (pump gasoline remember)?
Also can you defend your choice of high duration cams (typically turbo cars don't like overlap)?

Keo, you've just raised the bar to 690 WHP with your suggested bore. We're not looking for ultimate power, just specific output. Would you still recommend this, and why?

IMHO, the overlap issue is only an issue when your dealing with cast/log type turbo manifold. I think it's okay to use high duration cams on EQ style manifold, and when your looking for 600+hp, the EQ manifold well help alot.



If I wanted a safe 600+hp engine, I'd sleeve it. SInce your already sleeving and getting new pistons, I think going 92mm is a good idea since it's probably going to cost the same.

IMO, the best person to discuss this with is Mark @ Mazworx.

If the exhaust pressure in the manifold is higher than the boost pressure (like in a log type manifold) you'll get exhaust gas reversion (BAD!) but if the opposite is true (like in an equal length manifold) then you get intake air escaping out of the open exhaust valve which isn't terrible but not desirable. The advantage to the longer duration to me seems to come in where you realize it will make the cam profile less severe and thus play nice with the valve train. I'm sure there's a balance somewhere but to me the ideal cam design for a turbo car would have no overlap, yes?

Ideally, the less overlap the better on turbo cars, but I don't think you'd notice much difference if the cam isn't TOO extreme.

We're talking 600hp here, that's a lot of power from a 2L, you're going to need to pull out all of the tricks.

10:1 compression because I want torque before the giant turbo spools. Will it work on pump gas? Maybe, but meth+water injection will help that part of it.

I should have been more clear in the original post. I'll update it. Meth/water/nitrous injection and intercooler sprayers are off limits. The only consumable allowed is gasoline.

Wouldn't 'all of the tricks' net you something a lot more than 600 WHP? Possibly upwards of 800 or more? I'm betting there are a lot of tricks that could easily be left out.