308 V12 conversion begins

Yeah, I don't know what I type the first time I googled.

That green line at 850 ft-lbs point is the ignition timing that reads off the right side axis....maybe a little confusing. I added just becasue I though it was interesting how close the software came to what should be correct.

There won't be any track time in this car future while I own it for a number of reasons. First I couldn't stand to see it get damaged and second, but really more important is that clearly this car will be much faster than would be safe without a full race prep, cage and the like.

 

I've continued to be perplexed by the numbers my new simulation software spits out and I've found a couple more bugs. It's clearly a very powerful tool and I still trust the way it's calculating the wave/flow stuff, but it's making some assumptions that don't seem right and I'm having a hard time sorting out numbers for where the head flow wants to be in particular.....so I ordered more software.

In the past I've used a program called accelerator pro that a buddy had and it produced excellent results hitting peak hp within 2% or so on every engine I saw dynoed. The latest version is accelerator for windows and says it does all the stuff the old one did but costs much less, it was $100 vs $400 I think for Accelerator pro 5 or 10 years ago. It should be here in a few days and I'll re-run everything again. This software won't due the header or intake design and doesn't assume anything about how you're parts flow, it expects you to tell it the truth (head flow is assumed to be the head with the entire intake and exhaust systems attached) or it will tell you what optimal flow is.

 

Playing a little tonight I ran the simulator with all the V12 parts and specs but with a 308 bore and stroke. I thought you guys with actual 308 engines in your 308s might like the numbers.

Also (for pizzaman) tonight's project was to add some more pins to to a 308 flywheel for the efi project. It's now a 36-1 ford pattern so it will work with 1 of the 2 stock crank triggers and provide the ecu with enough position info to run the spark without distributors.
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I'm the same way. There is nothing wrong with mounting the trigger up front, but it's more reliable on the flywheel which is why so many OEMs do it in some version of this.

 

The power flat lines becasue the engine runs out of air. The ports are not big enough and the cam does not have enough duration to allow the cylinder to fill in the time available. I've been using 9k as the redline and optimizing around that, but if I picked a new redline at say 10k The ideal set up would be about 10 degrees more duration in the cams, about 10-15 cfm more flow, a little shorter header tubes, ect.

A 2 litter at 9000k would make abotu 2/3 what the 3 liter does. The advantage to short stroke is it allows higher rpm without exceeding max piston speed. A short stroke 2 liter at 50% higher rpm would make about the same hp as the 3 liter, but a little less due to increased frictional losses.

 

It's ferrari's, sort of. If you look you can see 2 pins darker then the rest, one almost right in front and the other almost right in back. Those 2 pins are for the stock trigger, I just added the other 33.

 

It's basically the same set up I'm using on the v12 flywheel. I like the trigger teeth on the flywheel because they can't ever move and the trigger in mounted securey and safely in the rear engine cover. A well done front trigger is fine, I just think this is a better way to do it.

 

Right. 9k is already more than plenty. I'm more likely to back off to 8500 then to go up to 9500.

 

I got the other brand software yesterday but I'm having a bit of trouble getting it to run right on my vista machine. It sort of works...but in an untrustworthy kind of way. So for the best number I've gotten out of it is about 650hp….but again that is with an output graph that has clear failures in some of the calculations. I'm going to uninstall it and have another go at it.

In the mean time I loaded the old version of accelerator (1993) to see what it had to say. It won't really model a 4V head or overhead cams so I needed to do some serious "estimating" of what the most relevant input should be. It started off around 600hp but after some playing it tells me an engine my size with a cam that can be made can clear 800 hp.

The 600 number is interesting in that Steve was kind enough to plug my engine into his older version of dynomation to see what it had to say. His software said about 720 with what he thought was abotu the best set up, but based on the output and his experience with the software felt 600 was the most probable output.
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I'm starting to see the headers are going to be pricey to build. Nice collectors are $200-$300 each it looks like and need 4...I'm going to end up with a couple thousand dollars into the exhaust system


....hopefully thr software pays off and it's right the first time.

This place seems to have a good selection of header building stuff at a decent price
http://www.coneeng.com/index.html

 

Yes, but no.

The haltech will accept 2 tripper inputs. one can be a single pin and the other a some number of evenly spaced teeth. The no part come becaseu the highest nuber of teeth it will accept is 72, 32 less than the number of teeth on the flywheel (and there is already an OEM sensor mount on the flywheel teeth ready to use). I had the same thought.

What you can do is add at least 2 pins to the flywheel then use a can sensor. That is the way I had mine set up, and the cam sensor gives you the ability to run full sequentail injection. I didn't do it on this car because it's running an E8 which doesn't have enough outputs to run sequentail injection on an 8 cylinder engine so I didn't see the point in addin gthe extra trigger.

 

You have been hoodwinked. Rotary valves have been around longer than engines and many engines have been built over the years that use them. There are several problems any of which would kill them.
The first is the precision required for them to seal. You have to have very tight tolerances which is ok, but then the dirty side (the parts that was in the combustion chamber) needs to still spin and seal….so you end up with leaking valves in very short order.
The second and the one of most concern to me is that the valves simply can’t open and close at a rate anywhere close to what can be done with a poppet valve. You may get more flow when the rotary valve is in the full open position, but that only happens for a small fraction of a second and everywhere else the flow is worse. This timing problem is the reason you can run very high compression and it’s not really a can run, but a must run high compression to maintain reasonable cylinder pressures with all the blow-down you get from the slow acting valves.

 

The software confict with this project continues.....the lastest engine sim software (accelerator for window) has a bug that doesn't allow it to run my engine. I thought it was just because I'd installed it on a vista machine when it only list compatability up to XP...but that's not the case. I pulled out my old laptop today that runs XP and installed the software on it.....same problem. I emailed the man, now I wait for the bug to be fixed I guess.

I don't know what it is about me, this project and software.......

 

it turns out it's way way easier to make stuff worse then it is to make stuff better