This is the 3.7L predecessor to the 3.7L 9000rpm set up. The 3.7L 9000RPM short block is done. But before I install it, this mid range monster is the R&D mule! The only thing they have in common is the displacement, everything else is completely different. Short block geometry, heads and intake are completely different between them two.
This is the 3.7L predecessor to the 3.7L 9000rpm set up. The 3.7L 9000RPM short block is done. But before I install it, this mid range monster is the R&D mule! The only thing they have in common is the displacement, everything else is completely different. Short block geometry, heads and intake are completely different between them two.
Nicely done!
Crazy question ... have you seen anyone modify fuel-injection heads like ours to direct injection?
Your neighbors must have the city noise infraction department on speed-dial.
This was at my place of work which is a very busy and noisy commercial zone. That's why I took it to work to tune it, no cars, no quiet neighborhood and must important its gated so no one can come in.
I sent him an e-mail. I'll let you all know if he replies....
Edit: He replied: He's fine and working on his projects. He did pull out of YouTube because it's a sham!! (I tend to agree! I don't know if I can be bothered to edit more Turbo Slug videos!?) I'm sure he'll get back to us serious Fiero gearheads once he's ready!
Rafe, I don't want to send this thread off on a tangent... but what do you mean that YouTube is a "sham"?
Patrick,
Let me explain YouTube in a on topic way.
I want you to fix my Fiero, I am not going to tell you what to fix, but my entire existence depends on you fixing my Fiero, so choose something to fix. Now, I am only going to pay you if you fix a minimum of 10 issues, but its only going to be a few cents per issue after that regardless of how in-depth the repair was. When you fix a 100 issues maybe then I will pay you minimum wage. On top of all of that, if you want to get paid, you not allowed to use certain tools, or perform fixes in certain ways that I decide on a on the fly basis. In fact if you have already used a tool that I decide to ban tomorrow, I'm not going to pay you for that fix anymore and make it harder for you to get paid for future fixes.
If you decide you just want to fix my Fiero for fun and don't want to make money, I'm going to advertise other mechanics, stores and especially politicians (even ones you don't like) on the wall of your shop facing the street whether you like it or not.
I'm still here!. The intention of my channel was to show my projects so others can see what is achievable with the 60* Iron head engine. It was never my intention to make money on it. But when YouTube changed the rules and started putting ads on videos to make money off them, that's when I drew the line. An old proverb says: "The one who gives to the rich will end up in poverty". Regarding this project, I have everything ready. Block is bored and honed and the rotating assembly is balanced and the camshaft is done. I'm still testing the 3.7L in the car and getting it ready for this years track days. Now I can book time on a Circuit to test and tune about an hour from my home. The plan is to keep tuning the current 3.7L and sometime before the end of the year install the long rod 3.7L short block. I know that SOME of you are real gearheads and enjoyed my channel, so I decided to get a Rumble account and start uploading the old and new content there. Here is the first video I uploaded. https://rumble.com/v27f1ek-...he-untold-truth.html
[This message has been edited by La fiera (edited 02-02-2023).]
much to my surprise, not all iron heads are created equal...
Up top are the Firechicken heads I was getting ported for my new 3.5x spinner...however... My old Fiero heads are clearly superior... The casting is much thicker around the exhaust ports which allowed me to get to >1.4" diameter but on the Firechicken heads the machinist thought it safe to limit them to 1-3/8" ... and I can't disagree...
Perhaps I'll ask him to D-port them to help make-up the difference...
[This message has been edited by lou_dias (edited 02-02-2023).]
How much heavier is the lz9 forged crank? They have the 58x trigger wheel.
I don't know exactly but the LX9 crank has at least 2 things that go against weight compared to any other 60* cast crank. The 1st one is that the LZ9 crank is forged and that automatically is heavier and the 2nd one is because the rod journals are bigger in diameter compared to the L44 crankshafts. So, yes it does have a handicap. When it comes to crankshafts, the important thing is not the overall weight of the crankshaft. What really matters is from where you take weight off. For example, on the 3.7L on the car now I made the crank lighter by 2 pounds but had to put almost everything back on it. So, all the weight I added to make up for the heavier rods and pistons was installed closer to the axis of rotation. So, even though the crank weights the same overall, the outermost diameter is lighter. Thus mimicking a super light crank! The throttle response and acceleration are the result of this approach.
[This message has been edited by La fiera (edited 02-05-2023).]
Originally posted by La fiera: Thank you! I've never heard of anybody doing direct injection. For performance reasons I would not use direct injection if I had the option.
What is your reasoning? I thought that direct injection is the reason today's stock motors are so much peppier than yesterdays.
Question: without going through the whole post, the block is a modified 3.4, yes? At least that's what I think seeing the F and the X-web on the casting. Bored over and longer stroke?
Originally posted by Notorio: What is your reasoning? I thought that direct injection is the reason today's stock motors are so much peppier than yesterdays.
That was my understanding, as well. If you browse through the different engine families on wikipedia, the DI versions always make more power than the MPFI versions. And most of them have a higher compression ratio than their MPFI counterparts. The DI allows the use of higher compression without knock.
What is your reasoning? I thought that direct injection is the reason today's stock motors are so much peppier than yesterdays.
Yes they are peppier but lack top end. For transient fueling and low RPM driving response is the perfect scenario because fuel gets delivered instantly at the combustion chamber instead of wasting time making its way down a manifold runner. If you look at all DI engines today they have one thing in common, they are turbocharged. At high RPM a DI engine in naturally aspirated form has to have the injector pulse cut shorter and shorter as the RPM increases because there is not enough time for the engine to inhale the air charge needed to match the amount of fuel needed to make the power requirements. So the only way to provide the necessary air needed to match the fueling requirements is to use a turbocharger. I don't do turbo engines, so DI is not desirable for my purposes. My aim is to place the injectors as high as possible to allow the cooling properties of the alcohol found in E85 to absorb as much heat as possible before that air/fuel charge makes its way into the combustion chamber. By doing it that way the oxygen molecules are brought closer together and the closer you can bring them together the more you can pack inside the cylinder. Using the DI approach does the opposite. No air charge cooling, the fuel needs to be at a very high pressure and that pressure has a negative effect on the fuel's temperature. Add to that the turbo, which also increases pressure and as the fuel, the compressed air has the oxygen molecules farther apart making the air less dense but the fact the air is being forced by pressure more molecules of oxygen can be shoved down the cylinder. But the ignition timing needs to be retarded to prevent detonation. My point is that DI has its place in the OEM fuel economy world and other application but I personally will never have a use for it because the type of engines I build. DI engines have big problems with oil caked valves and intake manifold runners because since the cleaning capabilities of the fuel acting as a detergent cleaning the intake and back of the valves has been eliminated, lots of low mileage cars must have the intake removed and blasted with walnut media to restore their performance. BMW was smart about it thought! Since the warranty work was too much to remove the manifolds and clean them the installed a water injection system as a "power booster"! No, it is not a power booster it is a means to keep the runners and back of the valves from oil caking and eliminate the warranty claims on intake manifolds and valve cleaning.
Question: without going through the whole post, the block is a modified 3.4, yes? At least that's what I think seeing the F and the X-web on the casting. Bored over and longer stroke?
Yes, it is the modified 3.4L block bored with the stock 3.31 inch stroke.
Originally posted by La fiera: If you look at all DI engines today they have one thing in common, they are turbocharged. At high RPM a DI engine in naturally aspirated form has to have the injector pulse cut shorter and shorter as the RPM increases because there is not enough time for the engine to inhale the air charge needed to match the amount of fuel needed to make the power requirements. So the only way to provide the necessary air needed to match the fueling requirements is to use a turbocharger.
The current GM LT series V8 engines are DI and NA and have no issue providing enough fuel with a 6000 rpm hp peak and a 6600 rpm redline in stock form.
The current GM LT series V8 engines are DI and NA and have no issue providing enough fuel with a 6000 rpm hp peak and a 6600 rpm redline in stock form.
Here is a modified one that makes 701 hp at 6800 rpm and is naturally aspirated
That's not impressive at all. One thing I notice while reading the article is that the author used HP as a way to compare efficiency instead of torque like the norm on engine building competition. There are LS based engines making over 1000HP NA at 11,000RPM non DI and with way less displacement, 360 CI to be precise. Search for "Spinal Tap LS". When I see that then I will become a believer DI can compete with the MPFI set ups. The reason DI engines are used in racing is due to their fuel economy, not their potential Lbs/ft per cube. This Katech 427 topped out at 625lbs/ft of torque at 5200RPM which equates to 1.46lbs/ft per cube which is not bad. My home built stock bottom end 207CI V6 with MPFI paired with a Megasquirt, iron heads, custom intake, cam and ported heads made 300lbs/ft at the wheels on pump gas. Since there is always an argument on what the parasitic losses are due to the trans and other things lets use the torque numbers at the wheels. That mighty Katech 427CI made 1.46lbs/ft per cube and the little 207CI made 1.45lbs/ft and again this is at the wheels, not at the flywheel like the probably $20,000 Katech 427. That 427CI converted to MPFI would gain another 200HP at least. Noticed that it is a 427CI not a 360 or something smaller. Big displacement is the way they can make that power which in reality is not impressive at all. But going to a 24 hour race, absolutely I'd go for the DI set up. I can see that article author is well aware that HP sells!
What paint did you use for this block? I tried to find a 2 part engine enamel in this color for my build but had to settle for a cast iron color which is close but not what I wanted.
What paint did you use for this block? I tried to find a 2 part engine enamel in this color for my build but had to settle for a cast iron color which is close but not what I wanted.
Just make sure the block is free of oil and grease. It will never peel off or fade. I use this brand of paint in all my blocks and heads and have never had a problem. Surface prep is paramount.
[This message has been edited by La fiera (edited 02-13-2023).]
I understand your preference is for the non DI motor, but to keep others from being put on the wrong path regarding the implied DI motor high rpm limitations, the only limitations I'm aware of are associated with fuel injector limitations, which have been addressed with injector and pump swaps and high pressure pump cam lobe modifications.
The 3.6L DI has had a 7200 rpm factory red line since 2012. Some have spun the previous LLT version above 8000 rpm (MagnumForce GB, 8300 rpm, linked to below), with a cam, valve spring swap and tune. One repetitive failure I've seen with every Mace cam upgrade in a 3.6L that I've read about, is no increase in compression ratio to maximize the duration increase benefit from the cams. There's a lot of speculation about the valve train also, no one really knows for sure at what point the stock springs need to be replaced, and opt for the stiffer spring upgrade. My point here is that all of the 3.6L motors except for the latest (LGX) use the same valve spring, regardless of some weight increases in valves suggesting a good bit of cushion, along with the rpm bump from 7k-7200k redline. There is only a slight difference in height between the LGX spring and the predecessor, and it has heavier intake and exhaust valves, I personally measured all 3 parts, the springs of which can be retrofit to the earlier motors. More duration on a camshaft regrind (Schneider Racing has experience with these motors in competition) and a little head work for insurance and I see no problem with making power at the rpm extremes with these motors with DI in place not to mention eclipsing 9k rpm. Porsche does it with the NA, DI GT3. GM doesn't have a big problem with carbon deposits on valves and it has been proven to be eliminated altogether with a good oil catch can system, since the oil is from the PCV system.
I understand your preference is for the non DI motor, but to keep others from being put on the wrong path regarding the implied DI motor high rpm limitations, the only limitations I'm aware of are associated with fuel injector limitations, which have been addressed with injector and pump swaps and high pressure pump cam lobe modifications.
I'm not keeping anybody from going DI, they can do whatever they want and I'd respect that. DI came about to reduce emissions and increase efficiency, not performance. Now, like you mentioned high pressure pump cam lobes and newer design injectors are needed to bring that performance up to par with MPFI. And they did an awesome job by adding more complexity to the system. But the more complexity is added there are more things to go wrong. I've seen many DI drivability problems with the fueling and 90 % of the times the culprit has been with the "high pressure pump cam lobe" wearing out. Besides complexity there's also the cost of the parts to upgrade the DI system to reach those high rpms. That's why I say its not for me, if others want to go DI it is their decision and that won't affect me one bit.
Originally posted by La fiera: I'm not keeping anybody from going DI, they can do whatever they want and I'd respect that. DI came about to reduce emissions and increase efficiency, not performance. Now, like you mentioned high pressure pump cam lobes and newer design injectors are needed to bring that performance up to par with MPFI. And they did an awesome job by adding more complexity to the system. But the more complexity is added there are more things to go wrong. I've seen many DI drivability problems with the fueling and 90 % of the times the culprit has been with the "high pressure pump cam lobe" wearing out. Besides complexity there's also the cost of the parts to upgrade the DI system to reach those high rpms. That's why I say its not for me, if others want to go DI it is their decision and that won't affect me one bit.
Understood, I'm just gently pointing out that your performance knowledge base coupled with the generalized statements can discourage with the assumption by others that they must be correct coming from an experienced motorhead, considering there are 3.6L swaps going on here. I'm sure some of what you've stated is true, I just haven't observed it with the GM platform, imports however, are a different story, particularly with BMW and VW at the advent of DI. I've made similar statements to yours in the past as a reason to keep it simple on projects, but have come to appreciate the benefit of the added tech & accept the additional labor in working with it. Making a project/plan work is part of the DIY experience. The cost is relative, it's a 4 cam motor, with 4 cam cost and benefits. I'm following your progress, not questioning your plan.
