Supercharged QV (take 3)-or is it a turbo?

I think you're right that SOME is good....but I'm losing about 300-400 cmf and 75 lb/hr or fuel out the exhaust. I'd like to get that down a bit.

I just got news from my buddy Vic that he's got a couple bikes to prep for a dyno shoot-out...at least 2 weeks before he can think about touching ferrari heads

 

The practice head got here. Now it's time to band saw the poor thing and see how much metal there is and where around the ports. It's just a fill-in until the bikes leave for bike week.

 

You're right, shorter pipes are better, but You can build a good system either way. In the single turbo system insulating the pipes solves most of the problem. A TT system can have shorter pipes, but 2 small turbos are not as efficient as 1 larger turbo. It probably comes out about a wash I'd guess. You just build what makes sense for the space and goals you have.

 

I'll keep posting the progress Russ. One concern for you is that the combustion chamber will almost certainly get a big bigger dropping the CR. It doesn't realy make any difference to me, but in an NA engine that already has low CR, it's less than ideal....you have a claimed 9.2 that is probably a real 8.5 that will drop to say 8.0 when it should be closer to 10 or 11. I'd guess getting the CR up a couple points where it belongs is probably good for at least another 5% more hp across the board.

We'll see how the porting goes. At first look, it appears there is no taper in the intake runners. Generally about 4 degrees taper works about the best. So the top of the port needs to be opened up quite a bit when you do the math starting at the seat. That's why the practice head is going on the band saw. The intake valves are also a bit small, maybe they will work, maybe not. If it needs bigger valves, that makes the taper problem worse.

On the air boxes, I think I'd try to put the stack below the box leaving the box just that, an open box. You'll be trying different versions for years to come

 

You're right, it is the CCs that are likely to change. Often, sinking the intake a bit works wonders on the flow. It basically forms a diffuser and helps the air flow into the cylinder. The problem is that combustion chamber volume goes up a bit.

Multi-angle valve jobs are the traditional way to get the seat width correct and choosing the right angles helps flow. The standard these days is radius seats. The whole valve seat becomes pat of the port/diffuser with just a slight flat to form the valve seat. The shape of seat is critical and 2 or 3 different radiuses may be used at different points to get it working right.

CR is most noticed at low rpm because that is where cylinder fill and pressure tend to be the lowest. But the truth is that the engines efficiency is dependant on CR. The higher the CR the higher the efficenty and the more hp the engien will make. But it is a diminishing return game, it's way more important to go from 6 to 8 than 8 to 10...but it's still probably 5% or so I think.

The thing to remember though is that doing the heads will add 10+%, losing 1/2 a point of CR will cost 1 or 2%. It's a big net gain, but the gain would be bigger if the CR is bumped as well.

 

Here's a pic of today's project...a tool to hold the valves open and hole the dail indicator. Ready for the flow bench.
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It's only taken me a year, but the heads, intake, headers are now actually at the head shop. I made the adapter to get them on the flow bench yesterday while I was there, so Vic should be all set. He's a bit busy at the moment, but did take a good bit of time yesterday to look everything over and said he might sneak into the shop today to try a couple things.

As a re-cap. I decided poor head flow was at the heart the lack-luster performance and they needed to be properly ported. The non-supercharged hp of my engine is currently about 260. I expect that to jump to about 335 after the porting and the boosted hp to be about 700....although I may turn the boost down a bit and keep the engine around 500-550 where it is now, it's plenty fast. We'll see.

I'm going to switch to the 328 intake cams which have a bit more lift. I'm also going to re-time the cams to a larger lobe separation angle. 107 is stock US, I'm currently at 109 which is stock euro. I'm thinking more like 114...I seem to be losing a lot of air out the exhaust and want to reduce the valve overlap a bit.

I've also been struggling with ECU problems, so I'n replacing the ECU...again. I’m having a real moral dilemma. A haltech E11v2 should handle it and I hear they have some nice updates coming for christmas. I know a motec M800 will do it without question and does more than the haltech...like traction control and individual cylinder mapping (to make it perfect). But then there is money. The Haltech can be had for about $1600. The motec is more like $5000 from a US dealer, but can be had from an Australian dealer for under $3000 equally equipped with the haltech (wire harness, programming cable, ect). So twice the price and the budget is tight........

 

It's a little bit my own fault. The first ECU I installed and it worked great for a few years, then I did the bigger blower and installed 12 ohm injectors...the manual said >12 injectors, and they didn't work. They sometimes worked...confused the heck out of me. When I finally figured it out I called to see about an external driver box and got talked into an E11. They released the E11v1, but quickly recalled it because it wouldn't read a motronic trigger properly and replaced it with the E11v2. The dealer I use said, well hey, you don't have a motronic trigger, let me see if I can can you a v1 at a good price. He got me one at a great price, an even swap for my used E6k. It turns out there were a few more issues that they didn't know about and aren't obvious and it took me basically a whole season to work through them. I'm down to 2 now, first it get's heat soaked in the trunk, I'm sure moving it to the passenger compartment would solve that as other are running them successfully. Second the O2 sensor doesn't read proberly...it reads and the change, but the numbers mean nothing....very confusing when tuning until I realized the numbers were gibberish. So it's not haltech,s fault...they knew the units were bad and recalled them.

Moving forward I'm just not sure what to do. I'm very comfortable with haltech set-up and tuning and it's a good unit and you get a lot for your money. The motec is a better unit and will do a lot more, at a price. I'm pretty sure they both have the same processor. The motec software just seems to have more of everything, haltech let you trim the cylinders, motec lets you map individual cylinders both in fuel and ignition. Haltech gives me 2 ignition maps, motec lets me input gear selection or wheel slip and traction control with the timing. It's a lot of money though....I don't know

 

Gerret was woring or to methods. A hydraulic turbine which never worked and building an electric motor into the bearing housing which is impractical due to the power requirements. Mercedes has a couple patents on mechanical drive schemes and there are a few other concepts out there, but all of them will cause the compressor to surge if you try and get low-end boost. My original point was to keep the low end boost I have, but get more effieciency and top end flow. Due to surging, the only low-end options are to either run multiple size turbines in parallel with flow diverter plumbing or simple let the compressor flow a lot of air and then by-pass most of it. It turns into a big mess.

I laid-out a twin-charge option, but again it just seemed needlessly complicated.

The final decision was to stick with the screw type compressor which has been working very well and find and fix the causes of the couple issues I was having. Mainly, heads that don't flow enough to feed the engine, excessive valve overlap, and an ECU that was misbehaving.

So now the heads are in the shop, I've design the parts to allow cam adjustment and will be making them soon and I'll be ordering a new ECU...as soon as I decide which one.

 

Yeah, my car is a QV.

I know that Wil who just SC'd a 2v is using way more fuel than he should be at power. That tells me he has the same problem I do on the QV with fuel and air going out the exhaust. Scott's SC'd 2v on the other hand seems to be getting more hp than the air suggests he should...I still don't understand that. The LSA stuff I'm messing with really mostly applies to boosted engines, not so much to an NA engine.

Anyway, I know the 2V heads flow worse than the QV heads and that they oversive exhaust problem is at least as bad. I've seen a bunch of people mension that the header is mis-aligned with the port on 2V engines....That tells me that either ferrari doesn't have a clue how to read drawings or they intentionally off-set the head to restrict the exhasut port a bit. I think it's a latter. I've seen Chevy engines pick up 10-12hp when the intake manifold gasket is raised .100" to obstruct the bottom of the port (in a race class that does not allow porting)...I think ferrari is doing the same thing on the 2v header.

Nick had a lot of work done on his 2v heads for his 3.5 liter and has said he felt they were maxxed out a at his 360+ hp. The 4 liter is getting 4v heads. You might give him a call. I've looked at a 2v head and I'm honestly surprised that is all the flow there is in it, but he may very well be right. If you want to find a strap head, I'm sure my buddy Vic would be willing to take a look at it and see what he feels he could promise you (he would need an intake and header to go with it, but they would not be harmed). Maybe he can do better than the guy Nick uses, maybe not....but there is still a lot to be gained in porting the heads.

I can tell you that I have a 750cc H-D race bike that Vic worked on. It's got nearly the same bore and stroke as the 308, same valve sizes, and it makes like 95 rwhp on pump gas (although at 9200 rpm). That's nearly 400 rwhp is a 308 did as well....and this is a H-D pushrod 2v engine. There is a lot to be gained over stock with propper heads.

 

I haven't ever worked with a motec, but an M800 is at the top of my list and that is the way I'n leaning. It does an awful lot of useful things. I'm trying to justify the cost over a haltech E11v2, which will no doubt run the engine well. I've got a couple request for quotes out on the motec stuff so I'll know exactly how much $ difference I'm talking about.

Which one are you using?