Honestly I don't know if there are the same E85 issues here with the percentage of alcohol. As I said, I haven't looked into it before. But I wonder if the "flex-fuel" sensors can detect the differences and signal the ECU to tune accordingly? That's what those sensors are for on production vehicles, but I don't know how accurate or sensitive they are.It seems like E85 is good for applications with a lot of boost as it helps preventing detonation and improves cooling. E85 is commonly used in Sweden in racing, drifting and drag racing. However the pump E85 is not what it used to be. The quality varies from E72 to E82 so it can not longer be used for serious tuning and racing. I prepared my car for E85 but gave up because of the varying quality.
Btw, I recently met a guy at a car meet who had an old super nice Fiat 500 with an Uno T engine. He has 257whp@2.3 bar boost running Premium 98 octane gasoline (just like I do with 1.6 bar boost) so obviously traditional fuel also works well. Maybe it is time to buy a bigger turbo .
Honestly I don't know if there are the same E85 issues here with the percentage of alcohol. As I said, I haven't looked into it before. But I wonder if the "flex-fuel" sensors can detect the differences and signal the ECU to tune accordingly? That's what those sensors are for on production vehicles, but I don't know how accurate or sensitive they are.
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And yes, 2.3 bar is a lot of boost.
Thanks for the Flex Fuel sensor info. The ECU I'll be using does support it but I haven't decided to go that route yet. I really like the advantages of E85 with a boosted application, but E85 is not widely available around here. And I've already acquired some components for my build that are not fully E85 compatible. I can always change a few components and add it later.Old post I happened to miss, but; Easy peasy, these are commonly used in the aftermarket on many standalone ecus, and even on some OEM ecus that have custom code to support an ethanol content input. Accuracy is typically in the realm of +/-5%, and 1% is a pretty typical resolution, both of which are more than enough.
Typically, these communicate two things - fuel temperature, and alcohol content.
And, at least on the Delphi or Continental units I've seen, they output each distinctly by varying the output frequency based on alcohol content, and the pulse width based on fuel temperature.
If you use an ECU which doesn't natively support this, you can buy off the shelf boxes which convert the sensors output to an analog 0-5V output, which most ecus can then use to blend between either two fuel tables, or interpolate along a table for the stoichiometric value of the fuel based on the alcohol content (or both ideally). Alternatively, with some coding and an ESP32, one could make their own translator as well.
As far as the recent findings - those are some encouraging numbers from what is undoubtedly a malaise era lump. I'm exited to see how a stock form 1500 responds to some boost . I think it'll surprise us.
I agree. The fuel consumption with the UT engine is much less compared to the 1500 when driving normally. Of course, the smaller displacement, injectors, perfect ignition, and air/fuel mixture help, but anyway. However, when driving hard the consumption easily doubles.On a somewhat related note, I also recall another test to see how adding a small turbo onto a 4-cyl engine affected fuel mileage compared to the same vehicle without the turbo. Interesting it actually improved fuel mileage under normal driving conditions (i.e. around town, not driven particularly hard). However if driven aggressively or under higher loads then the mileage was lower than the NA version.
I completely agree. And that's why I decided against it in the beginning. I guess I am terrified of the possibility of detonation with this particular engine; putting a turbo on a totally stock SOHC with no turbo spec pistons, no oil squirters, no special valves, etc. But your point about low boost is excellent. Plus I am doing a few other things to help manage thermal loads, which will also deter detonation. So I'll see how things go without flex fuel first. But I must admit it would be fun to be able to turn up the boost more with running E85.I think you should give up the idea of going flexi fuel. There is no meaning with it with the low boost setup you have in mind, unless the price will drop drastically on E85. I also expect the mapping would be more complex. And the fuel sensor is not for free.
I don't know where the limits are for these engines, but adding boost completely changes things when it comes to knock.I'm curious at what point the 1500 even becomes knock limited. I don't believe it reaches knock before mean best torque at 100kpa manifold pressure, certainly at some level of boost that'll change though....but just how much before it reaches that point?
I did some research on the subject of compression ratio and boost (in this case I'm referring to the static CR as a baseline, then determining the dynamic CR with boost). Like everything else, it depends on a lot of variables. But my view with the SOHC is the stock static compression for a US spec head* (around 8.2:1) is almost too low, even with up to 10 psi boost (*keep in mind we got the low compression head vs the "Euro spec" head you have over there). I plan to use a MLS head gasket to help with reliability. And they can be ordered in any desired thickness (they just add or subtract layers of steel). Therefore I think I may order a thinner one to increase the static CR. However I have not ordered the gasket yet because I want to do some calculations to determine how much the static CR (and therefore the boosted dynamic CR) will change as the gasket thickness varies.Have you thought about having a thicker head gasket to reduce compression? That's the way many BMW tuners do it here.
My experience with early VW engines (e.g. the "JH") is what lead to this Fiat turbo project. Also a similar design, and with very robust internals, the VW engine can handle quite a bit of boost (relatively) with all stock components. Honestly I have no idea just how robust the Fiat internals really are; Fiat enthusiasts seem to think the engine came directly from God and is perfect in every way, therefore it can handle anything. I'm not one of those people. But I tend to agree with Bjorn, the crank and rods are forged so they should be fine. To me the weak links are the pistons and valves. However the pistons have incredibly thick top ring landings and are overall fairly heavy, so they might do o.k. The valves are a different story. But SS stock replacements are available if they prove to be unable to handle the heat. The keys for my build are exactly what you said; keep the boost low (around .6 bar), and use a conservative tune. Combined with plenty of thermal management, detonation should remain in check.I have no qualms adding a turbo to the Volvo NA redblocks - similar (antique) SOHC design, relatively low static CR, iron block - but.. the Volvo motors have strong internal components.
I agree with you, the side scoops really don't bring in enough air to effectively supply a oil cooler. And the engine bay in general is rather hot without much overall air flow either. Although I know it has been done, I would not recommend mounting the oil cooler at the front of the car; the incredibly long oil lines to and from it would over tax the oil pump and cause a huge delay in circulation through the system. Plus any drain back will cause a long delay in oil feed upon start up. Perhaps if it is a dedicated race car where the vehicle is in constant motion and the engine is at constant redline, then a front mounted oil cooler might work. But not on a street car. Likewise, mounting it at the rear of the car still requires fairly long oil lines, plus there isn't a ton of air flow back there either. This makes the placement of a oil cooler difficult. Ideally you can keep the lines as short as possible. Same for the remotely mounted oil filter.Oil cooling question - where would the best place to mount a cooler be?
I have a filter sandwich and will buy a Stebro small cooler - but I'm trying to figure out the best placement it. The side scoops don't bring in a lot of air (I've tested them) - They need airflow of course.
Any examples of a small oil cooler? (Maybe it's been discussed in the thread - need to find it!)
I have a different opinion. I've modified the inside scoop and built a box to encapsulate the oil cooler to maximize the airflow. I also installed a small fan on top to suck the air if standing still or driving slowly. It works very well and I seldom see temps above 100⁰C.I agree with you, the side scoops really don't bring in enough air to effectively supply a oil cooler.