Started working on my next short block and my goal is 300WHP with Cast Iron heads, off the shelf parts, no custom pistons or rods, no boost, no juice and using an unconventional approach. Will I be able to make it? We will see! I can hear some of you already, same people that said 250WHP was not possible out of a 3.4 Iron head engine. It's pretty disappointing when someone goes through the trouble of a V8 swap with a bigger mass to haul around and heavier and here I am with a stock 60* V6 design almost matching V8 power in a different way.
I sincerely respect everyone's choice of engine swap so I expect you to respect mine.
I am curious, do you plan to do this with an off the shelf cam grind? I just don't know of any that are aggressive enough, 300WHP is not an impossible goal, but I believe it will take a solid roller cam and lots of RPM to get there, maybe even Falconer heads. This is like asking a 350 to make 500WHP through a non-vortec SBC head, It may have been done before, But i have never heard of it being done with factory heads.
Good Luck.
I recently built a 3.4 DOHC motor, my cams spec at 286 degrees duration seat to seat (236 at .050), This is a hydraulic direct bucket cam. I don't anticipate getting much over 275 hp at the crank. The intake is a short runner, with a massive plenum, and a 3" Throttle.
Very cool. What kind of power band would you be looking at? The only argument that can be made is the V8 powerband would be more ideal. Not to take away from you accomplishments by any means though, keep on keeping on. There will always be haters.
I can hear some of you already, same people that said 250WHP was not possible out of a 3.4 Iron head engine. It's pretty disappointing when someone goes through the trouble of a V8 swap with a bigger mass to haul around and heavier and here I am with a stock 60* V6 design almost matching V8 power in a different way.
I sincerely respect everyone's choice of engine swap so I expect you to respect mine.
Let the hating begin!!
Not hating here, however humor me and allow me to make a point or two. I will say your work on the 250 hp set was impressive and hats off to you. I am sure this one will be just as good.
First point, yes you make V-8 power in a different way. Trouble is you had to do a whole bunch of work to make that power. Your last build was pushing the limits and this one will be as well. Yes I think you can do it, but you can drop a V-8 in the car pretty much stock and make 250 hp with ease. No extra work needed. The V-8 has tons of HP to be found with simple bolt on parts, they can be taken way over 400 hp pretty easy. Now for a second point, you will say they are heavier. Yes they are. From a quick google search I get the LT1 at 550, the LS1 at 500 and the 3.8 at 450. (estimated due to differences in bolted on parts) I would argue that the V-8s ability to make more power easier is worth less than 200 lbs of extra weight.
All that being said, I will be watching to see if you can do it, as I love when people prove the crowds wrong.
Edited because you should always read it before you post it so the words are not out of order.
[This message has been edited by Easy8 (edited 01-02-2018).]
Lol... good luck! Especially with a light weight clutch, driveline loss won't be a huge factor, but you'll still need 320-330 HP at the crank to hit 300 at the wheels.
Basically, you're going to need three things to hit that number: -Outstanding port work. The "port" being the entire intake flow tract from the plenum to the valve... the engine doesn't care whether that's in the cylinder head or the manifold -Solid roller cam. Yeah yeah yeah, people like flat tappet cams for inexplicable reasons. Rollers are just better. Period. -High compression. 10:1 is not high compression.
With those big three in line and other details dealt with appropriately for the build, you'll hit the number. That's pretty much the max that iron heads are capable of, though.
Getting power out of an engine with mediocre head flow has always required getting everything other aspect of the build on point. If you're using shelf GM pistons, that's going to be difficult, as GM never built pistons to run high compression with iron heads. The iron head pistons will run 12:1 or thereabouts with the smaller chambered aluminum heads. I guess there could be an application with adaptable pistons, but then you're likely not to have the right wrist pin size, so then you have to bush the rods... etc.
In my experience, buying what the build needs is a better value than trying to adapt something that's close.
If you haven't been using gapless top rings... you should be.
shaving 3.6 DOHC pistons flat combined with longer rods will give you 3.5L and higher compression... using the Gen2/3 1.76" valve will also boost compression... GM rods are off the shelf at least up to 6"...
Just go for it and ignore any negative comments. I got 300 HP ( at the engine though) with a 3.1. It was done by a professional race engine shop though, and had a turbo. Everyone here said that was BS. V6s can make a lot of power. Nascar Bush series a while back was using only V6 engines that were using a single 4 bbl carb and they had no trouble getting 550 hp. New Ford GT is a twin turbo V6 and makes almost 650 hp in street trim.
from Ford
"The car is powered by a 3.5 liter twin-turbocharged EcoBoost V6 engine making 647 hp (482 kW; 656 PS) and 550 lbâ‹…ft (746 Nâ‹…m) of torque."
Lol... good luck! Especially with a light weight clutch, driveline loss won't be a huge factor, but you'll still need 320-330 HP at the crank to hit 300 at the wheels.
Basically, you're going to need three things to hit that number: -Outstanding port work. The "port" being the entire intake flow tract from the plenum to the valve... the engine doesn't care whether that's in the cylinder head or the manifold -Solid roller cam. Yeah yeah yeah, people like flat tappet cams for inexplicable reasons. Rollers are just better. Period. -High compression. 10:1 is not high compression.
With those big three in line and other details dealt with appropriately for the build, you'll hit the number. That's pretty much the max that iron heads are capable of, though.
Getting power out of an engine with mediocre head flow has always required getting everything other aspect of the build on point. If you're using shelf GM pistons, that's going to be difficult, as GM never built pistons to run high compression with iron heads. The iron head pistons will run 12:1 or thereabouts with the smaller chambered aluminum heads. I guess there could be an application with adaptable pistons, but then you're likely not to have the right wrist pin size, so then you have to bush the rods... etc.
In my experience, buying what the build needs is a better value than trying to adapt something that's close.
If you haven't been using gapless top rings... you should be.
Off the shelf parts for me is whatever I have on MY shelves. I've been developing the Supernatural engines for a while now and along with that the experimental parts, specially on the valvetrain. Camshaft technology has come a long way since the 70's so I don't need a roller camshaft. Lobe design in a flat tapped can almost match the roller cams. Yes, the roller cam has the advantage of friction over the flat tapped but the latter has an advantage on the roller on weight. Roller lifters are much heavier than the solid flat tapped. So, with the flat tapped I can run less spring pressure and have more throttle response due to the lower moment of inertia of the lighter lifters. You'd be surprised if you see how many experimental camshafts I have sitting on my shelves, from different engines. For the 60* I have about 4 and the cam for the 3XX is has bee on the shelf, also one of those went to my friend Blacktree.
As far as the compression my 3.4 is 10.85 not 10.00. The pistons for the 3XX are stock from an engine and the static compression will be 11.65.1. Unfortunately, for the 60* there is not much aftermarket like for other engines like SBC or LS, so that's where creativity comes into play and it seems that has been lost with this generation of hot rodders, specially the ones that think they know it all because they graduated from Google University. Its very easy to purchase a part and slap it on an engine and call yourself an engine builder but that is no fun for me. The fun part is get to your goal with whatever you have available and if you can make a couple of parts yourself its even better, the sense of accomplishemt is much better than just following the crowd.
I know I can make a 60* turbo and make 600-800hp with no problem but power is not what I'm looking for, balance is. My goal with this engine is to match or get very close to the same power-to-weight ratio of a Porsche 911 GT3 and the Acura NSX 2018 with whatever parts are available to me. I know these cars can drive themselves due to the amount of technology in them and that can make the owners of these cars feel like race car drivers. Me, I like it the old school way, raw, loud and difficult to tame. It's more fun to build your machine and drive your machine and develop a relationship with it, It'll give you years of satisfaction even though you fail a couple of times along the way, just don't give up!
So, for all of you that have a unique Fiero, weather is a V8, V6, L4 or whatever other transplant , I admire your tenacity and take my hat off you because you are unique people, just likeme!
[This message has been edited by La fiera (edited 01-04-2018).]
Lobe design in a flat tapped can almost match the roller cams.
"Almost"
quote
Originally posted by La fiera: Yes, the roller cam has the advantage of friction over the flat tapped but the latter has an advantage on the roller on weight. Roller lifters are much heavier than the solid flat tapped. So, with the flat tapped I can run less spring pressure and have more throttle response due to the lower moment of inertia of the lighter lifters.
Moment of Inetria applies to rotating components, not reciprocating components. What you're talking about has nothing to do with MoI. What's important in a valvetrain is the frictional power required to turn the cam at a given RPM. That's related to the contact load between the cam and lifter times the coefficient of friction between the two parts. The work that goes in to compressing the spring is returned on the closing side of the lobe... so only the frictional component matters. The contact load is driven by both inertial and spring forces, so weight does matter... however...
Yeah, valvetrain mass is important, but that's more from the point of view of achieving enough stiffness in the pushrods and rocker arms to accurately reproduce valve motion against a spring stiff enough to control valve motion at maximum design RPM. Lighter components allow less sping, but the whole tradeoff is more about achieving a stiff valvetrain than minimizing weight. Don't forget that the most serious rocker arms in the industry are STEEL and not aluminum.
Slightly heavier lifters require greater spring load, but the rollers reduce the friction to the extent that the frictional power required to turn to cam goes DOWN with a roller valvetrain. In every racing class where it's allowed, builders run roller cams. The extra lifter weight is worth it.
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Originally posted by La fiera: You'd be surprised if you see how many experimental camshafts I have sitting on my shelves, from different engines.
I don't think I would. An avid builder will have experimental parts around. *Most* of the time those are from failed experiments, though.
quote
Originally posted by La fiera: The pistons for the 3XX are stock from an engine and the static compression will be 11.65.1.
That's getting into the ballpark... I haven't built an iron head V6, so I'm less familiar with how much compression they can run on pump gas vice aluminum head engines. I was thinking 12.5, but that would probably be a race gas engine if using iron heads. Have you tried Singh grooves with high compression?
[This message has been edited by Will (edited 01-07-2018).]
Originally posted by La fiera: So, with the flat tapped I can run less spring pressure and have more throttle response due to the lower moment of inertia of the lighter lifters.
The correct term to use would have been just "inertia" (minus the "moment of"). Apparently, Will forgot to mention that. But he didn't forget to admonish you for using the wrong term. He does that a lot.
That said, Will is absolutely right about roller lifters. The benefit of roller lifters FAR outweighs the benefit of lighter weight lifters.
Honestly I am a believer and i think 300 whp is achievable. But i want to see if its streetable! and aggressive cam and high compression means higher octane (especially with iron heads to avoid pre detonation. I have seen similar goals with pontiac 350 motors (obviously with a higher hp goal) and with iron heads however it was not streetable because the high compression ratio and iron heads it need race gas. so my mind is open and i wish you the best of luck as i want to see how you achieve this goal.
Seen at SEMA is an easy way to get to 300 hp. This bolt on unit, just mounts to the head/block, uses a cogged belt drive directly to the the front of the crankshaft, and a 6 battery trunk array. Control module mounts anywhere and connects thru OBD connector. 2 hour installation, plus what you do for batteries. Includes 150 hp, 150 ftpnd electric drive motor, mounts for your application, belt drive and control unit, required cables. Makes any car a hybrid to increase power and mileage. Demo car was a 1957 Pontiac V8. When coasting and braking, motor acts as a generator to recharge the batteries. 6 battery set up takes 3 hours to charge. This is not an electric supercharger (that dont work btw).
The correct term to use would have been just "inertia" (minus the "moment of"). Apparently, Will forgot to mention that. But he didn't forget to admonish you for using the wrong term. He does that a lot.
That said, Will is absolutely right about roller lifters. The benefit of roller lifters FAR outweighs the benefit of lighter weight lifters.
I didn't forget. I infer that he understands inertia just fine. However, lightweight reciprocating parts only affect the moment of inertia of the rotating assembly indirectly when they require extra balancing mass on a rotating component. Unlike a crankshaft, a lighter valvetrain doesn't let the engine accelerate faster just by virtue of being lighter.
quote Originally posted by La fiera: You'd be surprised if you see how many experimental camshafts I have sitting on my shelves, from different engines.
I don't think I would. An avid builder will have experimental parts around. *Most* of the time those are from failed experiments, though.
Thanks for the complement Will but they are brand new and each of them is designed for a specific purpose and as a matter of fact each of my cams I give it a personal name based on their characteristics. For example, the cam that Blacktree has I named it "Le Mans" and he'll see why when he installs it.
Everyone talks about roller cams like they are invulnerable to wear, that flat tappets are the only ones prone to failure due to their design. But if you do a search in the net you'll find 1000's of roller lifter and cam failures specially on LS engines. This is just a little example.
I myself have replaced many lifters and cams from LS and other GM and Ford engines due to failure. That taught me a lesson. I haven't yet seen one of my builds with flat tapped cams hydraulic of solid failed. The reason is very simple, I use the correct oil with the additive package for my application. Don't think because an oil is synthetic is good for your flat tapped 2.8 or 3.4. They are very good mineral oils out there that because of the additive package is so good they out perform most of the synthetics sold in the US.
I didn't forget. I infer that he understands inertia just fine. However, lightweight reciprocating parts only affect the moment of inertia of the rotating assembly indirectly when they require extra balancing mass on a rotating component. Unlike a crankshaft, a lighter valvetrain doesn't let the engine accelerate faster just by virtue of being lighter.
Use some common sense for once and let your intelligence aside and try this exercise Will:
Get a Volley ball, bounce it up and down to the floor and back striking it with your hand at hip level as fast as you can. Time yourself for 15 seconds and write down the number of bounces. Do the same test but this time with a Basket ball and write the number of bounces and tell me:
-Which ball has the highest number of bounces in the 15 second span? -Which ball made your hand hurt more? -Which ball made your bicep, triceps, elbow and shoulder hurt more? -Which ball represents a heavy lifter? -Which ball represents a lighter lifter?
My 8 year old niece knows the answer to this Will.
Originally posted by La fiera: Use some common sense for once and let your intelligence aside and try this exercise Will:
My common sense agrees with that of Will.
When you have mass in a tappet, you need energy to accelerate it as the lobe lifts it. However, you get the energy back by the time the valve is shut. Over the time scale of a camshaft revolution, you've broken even.
Flywheel inertia is different. During a WOT pull, as the engine accelerates to redline, some energy is not delivered to the transmission input shaft; this energy is instead stored in the spinning flywheel.
The problem with the flywheel is that while its energy is not destroyed, when you lift the throttle at the end of a straightaway, you can't put the flywheel's energy to good use. You're slowing down, so you end up throwing away whatever energy you had stored in the flywheel.
I'd be more impressed to see you actually drive the car for a few thousand miles without it failing in multiple areas.
** This isn't an insult at all either, please don't take it that way. I was hoping for some performance numbers (times etc) on your 250whp venture.. that's why I'm baffled to see you going for yet more power but haven't actually made the car functional to handle 250whp yet?
Very interesting thread, not many are willing to spend time and money on the 60* platform these days.
[This message has been edited by Steel (edited 01-09-2018).]
Just to help those that may not know. Because a flat tappet lifter, the type the first generation 60 degree V6 has, has a flat surface to interact with the cam, a factor for design is that the rate at which lift increases againts cam rotation is limited. That limitation comes frome the need for the lobe to be gradual enough as to not contact the sides of the lifter throughout the arc of rotation. A larger diameter lifter allievates some of this, but a roller lifter offers the benifit of having a rounded profile at the end of the lifter, this provides clearance for a more aggresive ramp through the cams rotation. When a very aggressive roller lifter profile is used sliding friction from the cam and lifter interface is lower than a flat tappet, but side loading of the lifter becomes more of an issue that needs to be dealt with due to highly aggressive ramp rates. https://youtu.be/8VjFZMKvEwY
Just to help those that may not know. Because a flat tappet lifter, the type the first generation 60 degree V6 has, has a flat surface to interact with the cam, a factor for design is that the rate at which lift increases againts cam rotation is limited. That limitation comes frome the need for the lobe to be gradual enough as to not contact the sides of the lifter throughout the arc of rotation. A larger diameter lifter allievates some of this, but a roller lifter offers the benifit of having a rounded profile at the end of the lifter, this provides clearance for a more aggresive ramp through the cams rotation. When a very aggressive roller lifter profile is used sliding friction from the cam and lifter interface is lower than a flat tappet, but side loading of the lifter becomes more of an issue that needs to be dealt with due to highly aggressive ramp rates. https://youtu.be/8VjFZMKvEwY
I think that these compromises explain the high rocker arm ratios in GM V8s lately.
I think that these compromises explain the high rocker arm ratios in GM V8s lately.
The cylinder head design has everything to do with the rocker arm ratio and overall lift on the latest V8s. Early GM cylinder heads just dont have the head flow to make high use of higher valve lifts.
I'd be more impressed to see you actually drive the car for a few thousand miles without it failing in multiple areas.
** This isn't an insult at all either, please don't take it that way. I was hoping for some performance numbers (times etc) on your 250whp venture.. that's why I'm baffled to see you going for yet more power but haven't actually made the car functional to handle 250whp yet?
Very interesting thread, not many are willing to spend time and money on the 60* platform these days.
I understand you very clear Steel. The 3XX is on the works but the 250WHP Supernatural has some unfinished business. I'm not into 1/4 mile racing but my goal is for low 12's or high 11's to prove that power to weight ratio is the key. People go to great lengths to install LS engines and trans upgrades to boost performance and keep reliability and here I am with my little V6 matching or surpassing them. Of course drivability will suffer on a 60*V6 NA to match or surpass LS power but to each their own, I respect and admire those who go for the LS or other swap because that is what they want. You are right on the monetary part also Steel. No one from this forum is giving me one penny to help me get there, this is on my own. So just sit tight and wait and you won't be disappointed, be patient my friend!
Originally posted by La fiera: Thanks for the complement Will but they are brand new and each of them is designed for a specific purpose and as a matter of fact each of my cams I give it a personal name based on their characteristics. For example, the cam that Blacktree has I named it "Le Mans" and he'll see why when he installs it.
I wasn't being facetious... You have to be adventurous enough to get outside the box to try new things. Trying new things means, at least some of the time, trying things that don't work. You're obviously an adventurous builder, so it's no surprise you'll have a list of things, and maybe even corresponding parts, that you'd like to try.
quote
Originally posted by La fiera: Everyone talks about roller cams like they are invulnerable to wear, that flat tappets are the only ones prone to failure due to their design.
I don't know of anyone who talks like that.
Out of tens of millions of LS engines built, thousands of failures is hardly noteworthy.
Every NASCAR engine is an example of a "flat" tappet cam living under extreme conditions. Of course they literally flood the cam tunnel with oil; as in... floor to ceiling, no air volume left. Offies also have rounded flat tappets that work in pretty extreme conditions. Superbike engines run flat tappets and steel springs. Not all roller lifters are created equal either. The Cadillac CTS-V race cars used hydraulic roller lifters... Yes, a professional race engine using hydraulic lifters. They're good for over 7500 RPM... and moving LS7 sized valves too. There are also REALLY awesome roller lifters that eliminate the needle bearings at the roller axle in favor of turning the roller against a cushion of oil just like a main or rod bearing. This completely eliminates the roller lifter problem of pounding the needle bearings flat with extreme ramp rates accelerating enormous valves at ridiculous RPM.
quote
Originally posted by La fiera: Use some common sense for once and let your intelligence aside and try this exercise Will:
Get a Volley ball, bounce it up and down to the floor and back striking it with your hand at hip level as fast as you can. Time yourself for 15 seconds and write down the number of bounces. Do the same test but this time with a Basket ball and write the number of bounces and tell me:
Lol... Yes, it takes less force to reciprocate a lighter component. However, this translates to less FRICTION on the cam and does not reduce the engine's moment of inertia. But like I said, though heavier, roller lifters still have less friction against the cam lobe than flat lifters. The switch to roller lifters was worth 0.5 mpg in the L98. The difference is probably bigger now since the rest of the engine's internal friction has been significantly reduces since then.
Lol... Yes, it takes less force to reciprocate a lighter component. However, this translates to less FRICTION on the cam and does not reduce the engine's moment of inertia. But like I said, though heavier, roller lifters still have less friction against the cam lobe than flat lifters. The switch to roller lifters was worth 0.5 mpg in the L98. The difference is probably bigger now since the rest of the engine's internal friction has been significantly reduces since then.
Will I admire your intelligence and I see you are well informed about about specific racing teams using specific items. Literally down my street there are a lot of teams of different brands and I know personnel that works there and I get info on things that is insane! I have Riley & Scoot, Acura IMSA team, the majority of NASCAR teams, the place were NASCAR developments take place and the list is long, this town is know as "Racing City USA". I've seen some wicked prototype stuff on shelves and the money they spend on R&D is insane! That's why I said screw that, I'll just work with what I have and what I can get on my budget.
Some of my customers have lots of money and I can use that advantage to build their engines spending their money, I don't have that luxury.
I know the advantages of a roller lifter over a flat tappet but the advantage vs cost on a good custom set of roller lifters for my engine from Crower is not feasible. The set costs over $500. If I had money to throw away then I'd get 5 sets. With that kind of money I can get more things for the build. And with today's oil technology rollers are not the norm.
Yes, it is the intelligent way to go with roller lifters to make more power but most of the time the intelligent choice isn't always the smart one.
Cheers mate!
[This message has been edited by La fiera (edited 01-15-2018).]
Originally posted by La fiera: And with today's oil technology rollers are not the norm.
Show me a modern push rod engine using modern oils that doesn't incorporate a roller on the cam lobe... Even most OHC engines are using roller followers.
quote
but most of the time the intelligent choice isn't always the smart one.
The only engines with rollers are the american units, that I'm aware of. As far as the European and Asian OHC engines the y all use a bucket type lifter and have no roller units in them. My Abarth has a roller rocker on the intake cam lobe. The exhaust valve lobe rides on a bucket type lifter.
[This message has been edited by La fiera (edited 01-16-2018).]
The only engines with rollers are the american units. As far as the European and Asian OHC engines the y all use a bucket type lifter and have no roller units in
American engines are also the only ones using cam-in-block construction, and 2 valve heads over large bores. And even then, there are only 2 families left in automotive use. NASCAR finally allowed roller lifters in 2016, and If you where to ask any top American engine builder, they will tell you that a roller lifter is the better route to go for a performance build.
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In my experience, the people who tend to favor flat tappets are either newcomers to racing who are trying to save money or veterans who had a bad experience with roller lifters in the distant past. I think that both groups are making a grave mistake by not using a roller cam unless they compete in a class that specifically requires flat tappets. Yes, a roller cam and kit does cost more than a flat tappet cam and a set of lifters, but the cost of fixing an engine after flattening a cam or dropping a valve is much more expensive. It’s true that a roller lifter may fail occasionally – usually as the result of a broken valve spring or incorrect valve lash adjustment – but the likelihood of trouble is much less than with flat tappets. -David Reher of Reher/Morrison
The only engines with rollers are the american units, that I'm aware of. As far as the European and Asian OHC engines the y all use a bucket type lifter and have no roller units in them. My Abarth has a roller rocker on the intake cam lobe. The exhaust valve lobe rides on a bucket type lifter.
The because of the lower spring loads, the MPG gain wasn't worth pursuing in OHC engines until many years later.
GM OHC engines use roller finger followers with hydraulic lash adjusters in the cylinder heads. The Ecotec 4's, Atlas 4, 5 & 6 cylinder mills and the Northstar all used the same roller follower. Jessel even makes (or made) high performance versions for the Ecotec racing program.
BMW went to similar followers on their Valvetronic engines in the early/mid 2000's. In fact relatively few *modern* OHC engines still use buckets.
Matched set weighting the same to the 1/2 gram! Same will be done to the pistons. Then the Crank will be balanced to match new con rods, pistons, rod bearings and piston rings. After all that is done the rods will get ARP bolts and all the parts are going down the street to get Cryo treated along with the crankshaft!
I'm shaving almost 2lbs off the stock rotating assembly, that is not counting the lightened crank to match these components. That;s about an entire 2.8 piston with 2 wrist pins!
[This message has been edited by La fiera (edited 01-27-2018).]
There will always be haters.
Love reading about your work. I thought that I was hyper organized? 
Show me a modern push rod engine using modern oils that doesn't incorporate a roller on the cam lobe...
