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You know Larry Widmer said that he read every paper on "Combustion" he could get his hands on?
318 MAX fuel economy builds?
- Thread starter gagembassett
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You know Larry Widmer said that he read every paper on "Combustion" he could get his hands on?
Mike I am really interested in this set up. Is it just a matter of cutting the grooves and extending the holes of the spacer down lower into the intake plenum?
What kind of results did you see with the motor home engine? I am building a 440 with 413 RV heads now for my Travco RV. This MH engine has coolant flow through the intake and crossover ports in the heads. I was thinking about blocking this off to help keep the fuel and air charge cool to help prevent detonation.
Seems from reading your posts I might be better served to keep the coolant flow open to help atomization of the fuel charge and suppress detonation that way.
Ok what can you tell me about the 302 castings? Are they 318 Port? Can they be made to flow decent enough for a 360? Not 400 hp but strong 300 325 hp with a 220 @ .050 cam assuming proper parts used to compliment them? Are they hard to find?
I would keep the coolant cross-over, but dimple the floor of the plenum under the carb. Keep the intake ports as rough as possible. There is a thread somewhere on this site about slightly bending a carbide bit and having it chatter across the surface to tear it up. Wet flow provides a unique opportunity to give the fuel more time to vaporize (or fall out of suspension if not done properly). Here is a SBC intake with the sides carved with Powre Lynz and the floor dimpled.
Those marks look like the ones in the new TF 190 power port heads. Interesting.
Thank you sir. I would love a chance to bend your ear about my build, but I don't want to hijack this thread either. Any chance that your class would be available remotely by skype or something similar?
The 302 ports are almost identical to the older open chamber versions. The major difference is in the combustion chamber. It has a squish pad that looks similar to the older 273 heads; except the 302s squish pad is heart shaped, and the 273 squish pad is more squared off. Anything you've learned about the older 318 heads pretty much apply to the 302's as far as larger ports/valves etc.
As for availability, they were introduced mid-year 1987 (I seem to recall) and ran to the end of LA 318 production, 1991. I have a set in the garage from my dad's '90 Ramcharger.
No promises, but a recorded/edited version is planned.
I installed Pulstar plugs, no other changes, & my idle rpm increased. There is mileage & power in ign. After having the plugs in the engine for a few months, the engine dropped a cyl. One of the Pulstar plugs failed. If a more reliable version was available, I would use them. Thank Allah that people are willing to try new things, otherwise we would still be using the two piece, 18mm plugs that my vintage Harley used.
The Pulstar Plugs incorporate a capacitance effect by making the ceramic thin between the hex and the conductive interior. That thin spot is where they crack. The newer versions use an aluminum oxide ceramic which seems to hold up better than the older ones. Also, anybody that tried the Platinum Pulstars, don't hold that against them. The Platinums sucked, and Lou (CEO) knew it, but was pressured into putting them out anyways. Right now Pulstar showcases their Iridium plugs on their site. If you want a bit more punch, call them and special order their CNG Plugs. Those are copper core inconnel electrode versions, similar to our familiar Champions, but have the built-in capacitor. That is what my team runs.
Awesome. I'll hunt for a set of those then. Thanks for the time and help.
Mike I watched a youtube video about these plugs. Looks like it would be counterproductive to run these plugs with a multi spark ignition.
Are running pulstar plugs a better choice than an old school jacobs or MSD ignition system?
It once was believed that you could improve combustion by extending the firing line. Later it was discovered that extending the firing line was like tossing matches on a forest fire -- the fire was already started! Instead, the intensity of the HV spike is where it counts. Multi-spark (MSD) sends a 2nd, 3rd... spark into an already-burning ionized path. A single more intense spark will do more good than several weaker sparks. If you want to know how deep the ignition rabbit hole goes, look up Plasma Discharge Ignition (PDI). Arvind Servanisand created the Aqua Pulser ignition system that blows Pulstar away. I played with the Aqua Pulser for about a year, but couldn't keep spark plugs alive. Initially it would just burn the electrodes (like an arc welder). The last attempt used Brisk electrodeless (aircraft) plugs. It didn't burn the electrodes, but burned right through the ceramic! I still had misfires!!
I've seen YouTube videos of guys adding PDI to small engines and running them on water (thus the origin of the Aqua Pulser name). They don't run very well, BUT THEY RUN ON WATER!! The only modification is the PDI; no internal engine mods.
I've seen YouTube videos of guys adding PDI to small engines and running them on water (thus the origin of the Aqua Pulser name). They don't run very well, BUT THEY RUN ON WATER!! The only modification is the PDI; no internal engine mods.
I thought they had to super heat the water to get it to separate. Like running it in a tube in the exhaust before feeding the metering system?
You're thinking of the GEET Fuel Processor I believe. That was a totally different technology. It seemed to work best running on crude oil for fuel. It would also run on Mountain Dew (soda), used engine oil, and a host of other "fuels".
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Just to be technical the Carb "atomizes" the fuel but as it leaves the carb and into the manifold where vacuum plays a big part and travels to the cylinder and past the valve and into the chamber to where it gets compressed during the compression stroke all contribute vaporization and homogenization.
I bought a sp2p manifold for the 440/413 industrial head motor I mentioned earlier. Both the intake and heads have tiny ports for the cubic inches, similar to what a 360/ 318 head/sp2p combo would have. 413 industrial heads have 1.88 intake and 1.5 exhaust valve in a big block head!
If your first priority is fuel mileage, then I would start with the sp2p (unless I had something else on hand to try of course).
Just be aware that the combo of the small 302 heads and sp2p intake will limit the rpm of your 360.
I doubt my motor will ever have need to spin over 4k in my application. Peak torque will be somewhere around 2300 to 2400 rpm, and plan to gear the MH to lumber down the road at less than 2000 rpm @65mph.
Whatever else you do make sure you get the piston/gasket/head combo to give you good quench about .035 or so depending upon how much piston rock your short block has. Number one priority in my mind if seeking efficiency and detonation resistance.
According to Diamond piston calculator I'm looking at .039 Quench. I think I'll stick with an Edelbrock Performer manifold. They are easier to find and the ports look smaller than the 8007.
I say smaller but the port look like they are about the same size all the way to the head. The 8007 looks like it has fat areas where the fuel would just fall at low rpm use.
Just know going into it that your block will almost certainly need to be decked to get the quench number they claim. You can cheat it .010 or so using the Mr. Gasket thin head gaskets. Gotta measure everything out because getting anything above the effective quench range (about .055 to .060) will likely make your engine a detonation monster.
They don't claim anything. I assumed the deck height was factory. Then everything else had specs I entered. If I have to deck the block I can always use a thicker gasket and still be in pretty good shape. I figured .039 was pretty good from what I been reading.
.039 is a good number to shoot for. What i was trying to say is the deck heights on the blocks are all over the place and you don't know what you have until it is measured.
Most of them are much taller than the claimed stock spec so they have to be cut down in order to bring the piston crown at or close to zero deck.
Got ya.
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