ntsqd
technerd
Any plans to seal the inside of the engine castings? I.E. paint the insides with glyptal or something else to shed oil and seal any casting sand out of the engine?
improving flow for the 3FE’s top end (7 Viewers)
- Thread starter RockDoc
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- Thread starter
- #262
No, I've scrubbed everything down a couple times, and likely will again before it goes together. Don't want any paint chips coming loose and blocking the oil pump intake. Techline doesn't offer a DIY version of an oil shedding coating. I'll do a search of glyptal online, but I'm not worried about oil control on that side of things.
Really interesting build RockDoc 
.
I may have missed it but did you run the new valves through the flow bench? I have seen some interesting comparisons where the added tulip (like the originals) on the valve functioned in smoothing flow transition and keeping a venturi effect; versus increasing the open area at low lift with a really back cut valve like the replacements you have.
I've only gone through one of D Vizards books. Very informative, even if it was about minis
.
.I may have missed it but did you run the new valves through the flow bench? I have seen some interesting comparisons where the added tulip (like the originals) on the valve functioned in smoothing flow transition and keeping a venturi effect; versus increasing the open area at low lift with a really back cut valve like the replacements you have.
I've only gone through one of D Vizards books. Very informative, even if it was about minis
.- Thread starter
- #265
Got my junk back from the machinist. Head has been put together with Comp Cams components (110 lb seat pressure on the springs I'm told). They seemed pretty impressed with how well it went together for a hodge-podge of toyota, chev and ford bits. Chambers were right around the original 77cc after the valves were installed, and they shaved to give a touch over 75cc (75.3 he thought it was).
I'll have to think a bit on whether I'll coat the chambers or not. I would like to, but would need to rig an oven big enough to handle the head, and I'm not sure 300*F would be good for the valve seals... unless I can figure a way to heat the bottom surface of the head to bake the coatings, but leave the top exposed to cool air to keep from overheating the seals. I should probably wait to see how the coatings go on some of the less expensive parts before I make the call.
The crank apparently was dead on and required no balancing
hhmm so they gave the journal and thrust surfaces a quick polish and called it good.
As for the cost, she weren't cheap, and we'll leave it at that.
I'll have to think a bit on whether I'll coat the chambers or not. I would like to, but would need to rig an oven big enough to handle the head, and I'm not sure 300*F would be good for the valve seals... unless I can figure a way to heat the bottom surface of the head to bake the coatings, but leave the top exposed to cool air to keep from overheating the seals. I should probably wait to see how the coatings go on some of the less expensive parts before I make the call.
The crank apparently was dead on and required no balancing
hhmm so they gave the journal and thrust surfaces a quick polish and called it good.As for the cost, she weren't cheap, and we'll leave it at that.
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- Thread starter
- #266
Really interesting build RockDoc
I may have missed it but did you run the new valves through the flow bench? I have seen some interesting comparisons where the added tulip (like the originals) on the valve functioned in smoothing flow transition and keeping a venturi effect; versus increasing the open area at low lift with a really back cut valve like the replacements you have.
I've only gone through one of D Vizards books. Very informative, even if it was about minis
Thanks,
Unfortunately, the new valves require the guides be bored out before they'll fit, which kills doing a direct comparison of the 2 valves back to back. I've long since disassembled the "flow bench", so going back and checking now wouldn't be practical. In retrospect, I think I likely would have been ahead to get valves with a bit more tulip, but when it comes down to it, I'm just getting anxious to put my foot into it.
Cruiserdrew
On the way there
Cleaned up extremely nice.
Can't wait to see it go back together.
You wheeling in California this summer?
Can't wait to see it go back together.
You wheeling in California this summer?
- Thread starter
- #268
Alaska
I'm sure I'll be down your way again. Perhaps after I get some sliders. Or maybe for Pismo, if any of my northern cruiser friends follow through with going this time
(although Deny made the trip solo as well in 08)- Thread starter
- #269
Maybe a heat gun and some sort of formed "hotbox" would do the trick, heat up 2 chambers at a time and work along the head.
When is this experimental engine going in? You should really dyno your stock engine and then this one to get some good comparable before and after stats.
- Thread starter
- #272
I aim to have the mechanical stuff all together within a week or two. When it will go in is a question mark. I'm looking at moving the end of next month, and spending some time out of town between now and then. So I suspect it will be moved on a cradle and installed when I get settled in, but.... I may be struck by the urge to do a quick swap if it comes together quick and smooth.
The shop I had the head done at has a chassis dyno, so it would be a possibility to do before and after pulls (if they can get a good read out off of an auto, I assume they must be able to).
Looking at your crank i am guessing you have not read Vizards book on modifying pistons rods and cranks.
Not really surprising though, i found only four used copies on the web ranging from $139.oo to $201.oo.
I think i might sell my copy!
I ported and coated the exhaust ports in my 3B head but have not yet run it, i am waiting to see if it was worth it.
Not really surprising though, i found only four used copies on the web ranging from $139.oo to $201.oo.
I think i might sell my copy!
I ported and coated the exhaust ports in my 3B head but have not yet run it, i am waiting to see if it was worth it.
- Thread starter
- #274
Nope, just his "how to build horsepower" books. What are the big things he suggests in this book? Knife-edging and such? Or do I want to know at this point?
Yes knife edging de buring, polishing and drilling out the throws to lighten it up.
Does nothing for steady state HP but frees some up as the RPM increases.
In the case of a 383 goes a ways towards internally balancing and reducing the coupling effect of externally balanced cranks.
A good read but if that's what a used copy is going for i suggest renting one!
Does nothing for steady state HP but frees some up as the RPM increases.
In the case of a 383 goes a ways towards internally balancing and reducing the coupling effect of externally balanced cranks.
A good read but if that's what a used copy is going for i suggest renting one!
- Thread starter
- #276
Hmmm.. posting updates is getting a bit overlappy now that the this and the 2FE thread are converging. Some pics of recent developments.
Head blasted... will coat and bake tonight.
Piston all coated and assembled ready to install.
Bores glaze-broken and burnished with the PKSX powder (near cylinders done, those in the back not).
Pistons installed and bottom end covered up waiting on the cam to arrive.
Head is coated and baked
Head blasted... will coat and bake tonight.
Piston all coated and assembled ready to install.
Bores glaze-broken and burnished with the PKSX powder (near cylinders done, those in the back not).
Pistons installed and bottom end covered up waiting on the cam to arrive.
Head is coated and baked
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PabloCruise
SILVER Star
How did you end up baking the head? half way in the oven, halfway out?
What did you decide about the valve seals?
What did you decide about the valve seals?
- Thread starter
- #278
I ghetto-fabbed something involving a propane heater, an old oilpan, a heavy duty foil roasting pan, a piece of HVAC ducting.......
Only the face of the head was exposed to the heat. I used a spray bottle of water to keep the spring/valve assemblies cool on the other side. Maybe I'm wrong, but I would think enough heat would travel up the stem of the exhaust valve to the seal that they would have to handle 300*F normally anyway. Rather than risk it, I kept them cool.
- Thread starter
- #279
Did the exhaust manifolds this afternoon. Cilgen Satin Black thermal coating from TechLine. This stuff is solvent-based, so a respirator is needed. Decided I would do at least the base portion of the intake manifold too... if it seems to have adhered well once it's dried/cured I'll likely do the upper portion too. This stuff is moisture cure by the sounds of it. Can bake it to get it to dry faster, but it's a bit unclear if it needs exhaust heat to fully cure, or just goes through a slow cure from exposure to moisture in the air (seems I've read both in different places). Started tearing down the 3FE that will donate peripheral parts too. The harness on it seems a bit rotten, so I'll dig out a spare I have buried somewhere and decide which is in better shape. Still waiting on the camshaft.... probably sitting at customs
