- Joined
- Sep 26, 2003
- Threads
- 117
- Messages
- 11,199
- Location
- Lancaster, Ohio, USA
- Website
- www.tlcperformance.com
There is a date code on the side of the engine block, same format as cylinder head.
improving flow for the 3FE’s top end
- Thread starter RockDoc
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
PabloCruise
SILVER Star
Where 'bouts on the block?
Wile E Coyote
Out in the streets, they call it murder!
Just a note to perhaps save you some frustration when attacking the AFM housing. When you ordered the burrs, did you get at least one made for aluminum? Using a burr intended for steel/iron for aluminum will cause it to clog very quickly, and brings the suck even quicker when trying to do detail work. The burrs made for alum have much bigger flutes to address the clogging issue. Sorry if this is redundant info.
- Thread starter
- #84
Haven't gotten that far yet, but hadn't thought of this either. Saw some mention of the different cuts, but didn't really give it a second thought.
Also you have to kep th bits that are used for aluminum and steel seperate can't use it on aluminum thn switch over to steel. 
ntsqd
technerd
And while we're on that topic, it helps with aluminum to have a block of paraffin wax handy. Occasionally touch down the burr in the wax. Shouldn't take much. The wax will help keep the burr from loading up with aluminum without making the sprayed everywhere mess that using kerosene or WD-40 will do.
- Thread starter
- #87
Cool, I have lots of paraffin around after the moulding. The 2 burrs I've picked up so far are double cut, do I want single cut for Al, or something different? For all the Al I'm going to cut, I might just use some abrasive drums.
ntsqd
technerd
Aluminum specific burrs will look like those you have, only they'll be "missing" every other tooth.
Carbide burrs are the super-answer, if the budget will stretch enough for them.
A thot I just had, probably doesn't apply here since we're talking iron and steel, but a caution from my experience on steel. The splinters that carbide burrs will make from steel are truly super nasty. I've had two of them removed from my eyes, both times I was wearing safety glasses. The first one, as best as I can tell, got into my hair and then ended up in my eye overnight. The second one I saw coming at me, felt it hit my forehead just above my eyebrow, watched bounce off the inside of the safety glass lens, and stick into my eye.
When using a carbide burr on anything I now wear a welder's hat pulled down tight, a collared shirt buttoned at cuffs and collar, safety glasses, and when available (I NEED to buy my own!) a face shield.
Carbide burrs are the super-answer, if the budget will stretch enough for them.
A thot I just had, probably doesn't apply here since we're talking iron and steel, but a caution from my experience on steel. The splinters that carbide burrs will make from steel are truly super nasty. I've had two of them removed from my eyes, both times I was wearing safety glasses. The first one, as best as I can tell, got into my hair and then ended up in my eye overnight. The second one I saw coming at me, felt it hit my forehead just above my eyebrow, watched bounce off the inside of the safety glass lens, and stick into my eye.
When using a carbide burr on anything I now wear a welder's hat pulled down tight, a collared shirt buttoned at cuffs and collar, safety glasses, and when available (I NEED to buy my own!) a face shield.
Ouch, good to know.
Nice Thread....
- Thread starter
- #91
Well, I picked up most of the stuff I need to build the bootyfab flowbench today. Built a dummy cylinder out of a pop bottle (did I mention bootyfab), then discovered that with the eyebrowing of the cylinder and head, a dummy cylinder matching the engine bore won't do. 
On the bright side, a fast orange tub has just the right diameter to take in the full combustion chamber without touching any of the other passages in the head. edit: is the cylinder bore eyebrowed at the top of the block, or does the chamber extend over the flat top of the block 
I also did a quick check on the wall thicknesses of the runners. It looks like thicknesses are around 4mm (5/32") in many of the areas I could reach. That doesn't leave a lot of metal to work with.
Gonna have to be real careful wherever I go beyond smoothing out the surface texture, and limit how much of that I try. Good thing this is a spare head.
I also played around with some camshaft numbers the other night:
From Toyota - stock cam
Total duration 250º
Overlap 32º
Separation (109ºcam) 218ºcrank
Intake open –22º
Intake close 48º
Exhaust open –60º
Exhaust close 10º
From sealed power – stock replacement cam
0.05” duration intake 189º
0.05” exhaust duration 193º
overlap 27º
Separation (109ºcam) 218ºcrank
Intake lift (0.251”cam) 0.377” less lash valve
Exhaust lift (0.257”cam) 0.386” less lash valve
Deductions
Max intake lift at 102º aTDC
Max exhaust lift at 115º bTDC (65º aBDC)
0.05” intake “open” ~8º aTDC
0.05” intake “close” ~18º aBDC
0.05” exhaust “open” ~30º bBDC
0.05” exhaust “close” ~20º bTDC
3/4 lift is about 0.276” (stock cam)
2/3 lift is about 0.25” (stock cam)
From matt.mcinnes' 2F-ETI build – aftermarket cam
total duration 280º
0.05” duration intake 222º
0.05” exhaust duration 222º
overlap 60º
Separation (112ºcam) 224ºcrank
Intake lift (0.296”cam) 0.435” less lash valve
Exhaust lift (0.297”cam) 0.437” less lash valve
Deductions
Max intake lift at 108º aTDC
Max exhaust lift at 112º bTDC (68º aBDC)
0.05” intake “open” ~2º bTDC
0.05” intake “close” ~40º aBDC
0.05” exhaust “open” ~46º bBDC
0.05” exhaust “close” ~4º bTDC
3/4 lift is about 0.322”
2/3 lift is about 0.288”
So, I'll test lift up to 0.45”, but look for optimizing performance in the 0.25” - 0.35” range as the valves spend more time in this range than at max lift.
On the bright side, a fast orange tub has just the right diameter to take in the full combustion chamber without touching any of the other passages in the head. edit: is the cylinder bore eyebrowed at the top of the block, or does the chamber extend over the flat top of the block I also did a quick check on the wall thicknesses of the runners. It looks like thicknesses are around 4mm (5/32") in many of the areas I could reach. That doesn't leave a lot of metal to work with.
Gonna have to be real careful wherever I go beyond smoothing out the surface texture, and limit how much of that I try. Good thing this is a spare head.I also played around with some camshaft numbers the other night:
From Toyota - stock cam
Total duration 250º
Overlap 32º
Separation (109ºcam) 218ºcrank
Intake open –22º
Intake close 48º
Exhaust open –60º
Exhaust close 10º
From sealed power – stock replacement cam
0.05” duration intake 189º
0.05” exhaust duration 193º
overlap 27º
Separation (109ºcam) 218ºcrank
Intake lift (0.251”cam) 0.377” less lash valve
Exhaust lift (0.257”cam) 0.386” less lash valve
Deductions
Max intake lift at 102º aTDC
Max exhaust lift at 115º bTDC (65º aBDC)
0.05” intake “open” ~8º aTDC
0.05” intake “close” ~18º aBDC
0.05” exhaust “open” ~30º bBDC
0.05” exhaust “close” ~20º bTDC
3/4 lift is about 0.276” (stock cam)
2/3 lift is about 0.25” (stock cam)
From matt.mcinnes' 2F-ETI build – aftermarket cam
total duration 280º
0.05” duration intake 222º
0.05” exhaust duration 222º
overlap 60º
Separation (112ºcam) 224ºcrank
Intake lift (0.296”cam) 0.435” less lash valve
Exhaust lift (0.297”cam) 0.437” less lash valve
Deductions
Max intake lift at 108º aTDC
Max exhaust lift at 112º bTDC (68º aBDC)
0.05” intake “open” ~2º bTDC
0.05” intake “close” ~40º aBDC
0.05” exhaust “open” ~46º bBDC
0.05” exhaust “close” ~4º bTDC
3/4 lift is about 0.322”
2/3 lift is about 0.288”
So, I'll test lift up to 0.45”, but look for optimizing performance in the 0.25” - 0.35” range as the valves spend more time in this range than at max lift.
Last edited:
ntsqd
technerd
When I worked in road racing Schroeder did our cyl heads and our Rotary engine side plates. His advice was that the secret to 4 stroke power was low lift flow. Based on that, I would start looking to improve the flow at about .050"-.075" off the seat.
- Thread starter
- #93
Wow, that low?!! Kind of surprised by that, but good to know.
I guess it makes sense, it's at low lift as the valve is closing that inertial flow is going to cram that last bit into the cylinder.
Last edited:
- Thread starter
- #94
Flow-bench
Told ya it was going to be booty-fab.
So here are some pics of the almost finished flow-bench. Note the bench-building/sChat-posting fuel, thanks to Tonkota for reminding me of McEwan's. You can see the ABS pipe leading to the cone-shaped expander and the model cylinder resting against the head. The angled slat against the wall is for the manometers.
The mean green 11 amp sucking machine. When in use, I'll remove the bag and the filter to maximize suction to the bench. Oh yah, it's fuel injected.
Using the vacuum hose to allow flexibility in mating it with the ABS, note the variable bleed valve (a slot in the pipe and a sleeve made out of pop-bottle plastic and duct tape). The bleed valve, when used in conjuction with a orifice plate, will allow the bench to be zeroed in to maintain consistency of performance between sessions.
The expansion cone, which smoothly transitions from the diameter of the ABS to the diameter of the dummy cylinder. Constructed out of pop bottle plastic...... You can see the piece of small diameter tubing coming out of the 22.5* elbow, that will be the sampling point for the primary manometer.
The dummy cylinder is made out of a Fast Orange tub with the bottom carefully cut out. The diameter is larger than the actual cylinder, but this is needed because the combustion chamber in the head is wider than the bore. Ideally the dummy cyl. should be the same length as the stroke (and the cone 2.5-3 times the stroke), but I'm not too worried...
The reservoir for the manometers. Since the surface area of the liquid (water and red food coloring) is much larger than the cross-sectional area of the manometer tubing, the level of the fluid on the atmospheric end (the ziploc container) will essentially remain stationary.
The manometer bits.... The tubing is hard plastic tubing from the aquarium section in a pet shop, and will be connected to the sampling points (the 22.5* elbow and a probe I haven't figured out yet) by flexible aquarium air tubing. I'll run an old tape measure up between the 2 tubes to allow for making readings.... Basically for anyone who isn't familiar with a manometer, it is a tube filled with fluid, one end open to the atmoshpere (ziploc container), the other open to the location you are sampling. The difference in fluid level between the surface open to the atmosphere and the surface exposed to the "sample" pressure gives you the difference in pressure. My understanding is that most of the work will be at less than 18" of water, I'll know for sure when I first fire up the vacuum. The tubing from the sample points to the manometer will run up to the ceiling, then down, to minimize the chance of sucking water into the vacuum if I accidently close a valve and get full vacuum.
Tried making a model valve today too, but that didn't work out. I'll give it another try, and if it doesn't work, I may just have to sacrifice the valves that came out of the head.
Curtis.
Told ya it was going to be booty-fab.
So here are some pics of the almost finished flow-bench. Note the bench-building/sChat-posting fuel, thanks to Tonkota for reminding me of McEwan's. You can see the ABS pipe leading to the cone-shaped expander and the model cylinder resting against the head. The angled slat against the wall is for the manometers.
The mean green 11 amp sucking machine. When in use, I'll remove the bag and the filter to maximize suction to the bench. Oh yah, it's fuel injected.
Using the vacuum hose to allow flexibility in mating it with the ABS, note the variable bleed valve (a slot in the pipe and a sleeve made out of pop-bottle plastic and duct tape). The bleed valve, when used in conjuction with a orifice plate, will allow the bench to be zeroed in to maintain consistency of performance between sessions.
The expansion cone, which smoothly transitions from the diameter of the ABS to the diameter of the dummy cylinder. Constructed out of pop bottle plastic...... You can see the piece of small diameter tubing coming out of the 22.5* elbow, that will be the sampling point for the primary manometer.
The dummy cylinder is made out of a Fast Orange tub with the bottom carefully cut out. The diameter is larger than the actual cylinder, but this is needed because the combustion chamber in the head is wider than the bore. Ideally the dummy cyl. should be the same length as the stroke (and the cone 2.5-3 times the stroke), but I'm not too worried...
The reservoir for the manometers. Since the surface area of the liquid (water and red food coloring) is much larger than the cross-sectional area of the manometer tubing, the level of the fluid on the atmospheric end (the ziploc container) will essentially remain stationary.
The manometer bits.... The tubing is hard plastic tubing from the aquarium section in a pet shop, and will be connected to the sampling points (the 22.5* elbow and a probe I haven't figured out yet) by flexible aquarium air tubing. I'll run an old tape measure up between the 2 tubes to allow for making readings.... Basically for anyone who isn't familiar with a manometer, it is a tube filled with fluid, one end open to the atmoshpere (ziploc container), the other open to the location you are sampling. The difference in fluid level between the surface open to the atmosphere and the surface exposed to the "sample" pressure gives you the difference in pressure. My understanding is that most of the work will be at less than 18" of water, I'll know for sure when I first fire up the vacuum. The tubing from the sample points to the manometer will run up to the ceiling, then down, to minimize the chance of sucking water into the vacuum if I accidently close a valve and get full vacuum.
Tried making a model valve today too, but that didn't work out. I'll give it another try, and if it doesn't work, I may just have to sacrifice the valves that came out of the head.
Curtis.
You needed new ones anyway's! Great Ghetto fab work. I can't wait to see how this works out!
ntsqd
technerd
Something that just occurred to me is that plastic electrical conduit has much larger radius' in their 90's.
FFT.....
FFT.....
RockDoc,
Do you have any performance bench marks for before and after comparison? All this work should be heavily quantified. What are you going to use as your inputs to compare stats later?
Do you have any performance bench marks for before and after comparison? All this work should be heavily quantified. What are you going to use as your inputs to compare stats later?
- Thread starter
- #98
I'll make an orifice plate or two to act a standard for adjusting the "bleed valve" each time I warm it up for use. That should keep it pretty close from run to run. I'll note atmospheric pressure when I run it, but I don't think that will make for much error. No intention to compare to a different head at this time.
If you are talking engine performance benchmarks, I ran a few timed acceleration runs pre- and post-valvebody swap, I'll do more with this when it comes to swap time. I'm considering swapping the peripheral stuff step-wise before the head too, to see what each of those does (AFM, TB, maybe even the injectors and manifolds).
Won't be much activity on this for a couple weeks, I'm headed back to Manitoba for Christmas tomorrow.
Happy Holidays,
Curtis.
If you are talking engine performance benchmarks, I ran a few timed acceleration runs pre- and post-valvebody swap, I'll do more with this when it comes to swap time. I'm considering swapping the peripheral stuff step-wise before the head too, to see what each of those does (AFM, TB, maybe even the injectors and manifolds).
Won't be much activity on this for a couple weeks, I'm headed back to Manitoba for Christmas tomorrow.
Happy Holidays,
Curtis.
Last edited:
- Thread starter
- #99
Well, I haven't done much since the last post, holidays and all.
I picked up copies of David Vizard's How to Build Horsepower vol. I and vol. II. These are really well put together, and I'd recommend them to anyone rebuilding, or looking for ways to get more juice. (I've added links to the first post) They compliment Dalton's book quite well, giving a more thorough treatment of the engine as a whole, and how to choose the right combination of parts (generally focussed on V8s though), while not delving into DIY head modification anywhere near as much as Practical Gas Flow.
I've decided to go with the SBC valves Jim suggested, working on getting them now. I'm hoping they'll be pretty good as-is, as I don't look forward to the prospect of turning them for an improved profile. A definite plus is the undercut stems the intake valves have, to reduce their cross-section within the port/valve bowl.
Randy has the injectors back from cleaning and balancing, and should have the throttle body modification wrapped up soon, once some parts come in. I believe he will have some photos and a description of the process to post up then.
I finally got started on making the plaster models from the silicone moulds. Not sure if the first attempt is going to work, or will be chocked up to learning. I'll get some photos and describe the process once I it works out.
Fired up the flow bench. I haven't done anything for calibrating it yet (making orifice plates and putting a scale on the manometers), but it is obvious that it is going to work as intended. I'll need to find a way to hold the valves stationary with the vacuum running, as they like to suck into the chamber to allow more flow. Right now I am thinking I'll use a pair of Vice-Grips with rubber in the jaws to protect the valve stems. I was playing around with piece of thread being sucked into the port. From this it seems that most of the flow goes down and through the short side of the valve head, as I couldn't get the thread to flow past the valve guide/stem to the far side of the valve head. This leads me to believe that some attention paid to improving flow around the stem (undercut), guide and guide boss will pay off. It also points towards the flow being down onto the valve (as Jim suggested) rather than across the valve.
I guess that's enough for now, especially since there are no pics in this post.
I picked up copies of David Vizard's How to Build Horsepower vol. I and vol. II. These are really well put together, and I'd recommend them to anyone rebuilding, or looking for ways to get more juice. (I've added links to the first post) They compliment Dalton's book quite well, giving a more thorough treatment of the engine as a whole, and how to choose the right combination of parts (generally focussed on V8s though), while not delving into DIY head modification anywhere near as much as Practical Gas Flow.
I've decided to go with the SBC valves Jim suggested, working on getting them now. I'm hoping they'll be pretty good as-is, as I don't look forward to the prospect of turning them for an improved profile. A definite plus is the undercut stems the intake valves have, to reduce their cross-section within the port/valve bowl.
Randy has the injectors back from cleaning and balancing, and should have the throttle body modification wrapped up soon, once some parts come in. I believe he will have some photos and a description of the process to post up then.
I finally got started on making the plaster models from the silicone moulds. Not sure if the first attempt is going to work, or will be chocked up to learning. I'll get some photos and describe the process once I it works out.
Fired up the flow bench. I haven't done anything for calibrating it yet (making orifice plates and putting a scale on the manometers), but it is obvious that it is going to work as intended. I'll need to find a way to hold the valves stationary with the vacuum running, as they like to suck into the chamber to allow more flow. Right now I am thinking I'll use a pair of Vice-Grips with rubber in the jaws to protect the valve stems. I was playing around with piece of thread being sucked into the port. From this it seems that most of the flow goes down and through the short side of the valve head, as I couldn't get the thread to flow past the valve guide/stem to the far side of the valve head. This leads me to believe that some attention paid to improving flow around the stem (undercut), guide and guide boss will pay off. It also points towards the flow being down onto the valve (as Jim suggested) rather than across the valve.
I guess that's enough for now, especially since there are no pics in this post.
- Thread starter
- #100
Some more pics of the slow progression.
Making a plaster model from one of the silicone moulds. The idea here is the make the cast in 3 pieces (up to the mid line of one port, from the mid line of the first to the mid line of the second, and up from the second) to ease removal of the mould, and allow for easy viewing of the port shape when the pieces are separated. I've got some alignment holes cut in the first pour, so now I need to cover the surface with a release agent (vaseline) and make the second pour.
Here is a pic of the pre-made orifice plates I've picked for calibrating/standardizing the flow bench between sessions. The 45 will be used to calibrate for high-lift/flow tests (and I suppose tests of the manifolds and other high-flow components) while the CD will be used to calibrate for low-lift/flow tests.
Here's the method I am going to try for holding the valves to the proper lift for each test. The vacuum tries to pull the valve into the chamber and open it up for more flow, so both valves will have to be restrained. It simply consists of a slit piece of rubber hose, with a pair of vice grips holding it tight. With this set-up, it is still plenty easy to get in with a set of vernier calipers to measure/set the valve lift.
Here are a couple simple tools I've made to try and identify some of the problem areas. The first is a ball of wax on the end of a piece of wire. By inserting this down into the port and valve bowl, it will be possible to discriminate areas of quality flow (the manometer will register a large restriction of flow when the ball is in such an area) from areas of poor flow (the manometer will register little effect when the ball is in such an area).
Similarly, I've placed a wad of wax in one area on the head of an intake valve. When I rotate the valve, I'll be able to tell if the distribution of flow around the valve is even, or if it is largely going down the far (or near) side of the valve.
Making a plaster model from one of the silicone moulds. The idea here is the make the cast in 3 pieces (up to the mid line of one port, from the mid line of the first to the mid line of the second, and up from the second) to ease removal of the mould, and allow for easy viewing of the port shape when the pieces are separated. I've got some alignment holes cut in the first pour, so now I need to cover the surface with a release agent (vaseline) and make the second pour.
Here is a pic of the pre-made orifice plates I've picked for calibrating/standardizing the flow bench between sessions.
The 45 will be used to calibrate for high-lift/flow tests (and I suppose tests of the manifolds and other high-flow components) while the CD will be used to calibrate for low-lift/flow tests.
Here's the method I am going to try for holding the valves to the proper lift for each test. The vacuum tries to pull the valve into the chamber and open it up for more flow, so both valves will have to be restrained. It simply consists of a slit piece of rubber hose, with a pair of vice grips holding it tight. With this set-up, it is still plenty easy to get in with a set of vernier calipers to measure/set the valve lift.
Here are a couple simple tools I've made to try and identify some of the problem areas. The first is a ball of wax on the end of a piece of wire. By inserting this down into the port and valve bowl, it will be possible to discriminate areas of quality flow (the manometer will register a large restriction of flow when the ball is in such an area) from areas of poor flow (the manometer will register little effect when the ball is in such an area).
Similarly, I've placed a wad of wax in one area on the head of an intake valve. When I rotate the valve, I'll be able to tell if the distribution of flow around the valve is even, or if it is largely going down the far (or near) side of the valve.
