- Brian EParticipantAugust 9, 2020 at 2:16 pmPost count: 37
Disclaimer……..These are my opinions, based on tons of research, and lots of engine building, head building, experimenting, and trying different combo’s. I have never built the same engine combo twice. I always change at least one thing hoping to make the next combo better, and learn from each combo.
A tight deck is not the cure all for running cool, it is just one of the many things that help contribute to an efficient burn in the chamber. The more efficient the entire combo is, the more power it will make with less heat. It has been known for 100 years a tight deck has many more benefits than a .100″ deck. It is also know that too low of compression will build heat rather than building power. Without sufficient compression the incoming fuel mix is slow moving and collects in the chamber edges rather than staying atomized. This makes for a super slow burn needing way more timing advance, and sends most of the power out the tailpipe in un-burned hydrocarbons. Same reason semi-hemi heads need 36-38deg. advance to make any power. Slow burning flame needs a lot of time to get all of the power out of it.
Lots of guys get into trouble trying to put a w110 cam into 1600 with 8.0cr. The cam is too big for the small CC’s, the low compression makes for a very soggy bottom end and very slow burn. The huge down low load with almost no bottom end power, and a slow hard to light mixture makes it super easy to detonate.
The compression needs to match the cam duration , elevation, octane rating, and intake valve closing point. Along with a tight deck, the higher compression makes the incoming mixture stay atomized in the chamber, and keeps it from collecting around the edges of the chamber and up on the squish bands. This makes for a quick, efficient burn that needs less timing advance, and less advance means less negative work on the top of the piston. Being at high elevation makes the low compression even worse. Not much air up there to even compress.
I always build with the intention of using 91 octane. The higher the compression, the higher the octane needs to be to keep detonation down, but the higher compression also makes way more power, and if it is done correctly the heat isn’t an issue. I think the extra $2-3 per tank is worth the extra power for sure. Low compression, and in-efficiency is causing the engine to work extra hard, creating more heat.
If you run modern style heads, you can have the best of everything. The new AA500 heads, and the CNC panchitos have 60+cc chambers. After un-shrouding the valves on a 40×35 AA500 heads, I end up with 65cc. On a 94×84, .040″ deck, 65cc chambers, you end up with a perfect 9.1cr. This is what Josh B. is running on his bus, and he hauls ass all over in it.
The entire engine needs to be designed with a specific use in mind, and each part needs to complement each other. One wrong component can mess up the whole package. Not all the parts are available off the shelf. I think 1 1/2″ heater boxes would be perfect for a 1968-2180cc bus engine, but you would need to get some, cut them open and add fins to them so they makes some heat. I would not run stock boxes on anything larger than a 1915cc. Too much of a plug, holding too much heat in the heads, and messing up the combo.
Here is an engine load for you…This is a local guys limo bus I built the engine for.
Its a monster, and it weights about 5500lbs, and then it gets 8-12 girls (sometimes “larger” women) added almost every time it heads out. He does wine tours and bachelorette parties in it. He has to pull the steepest longest hill around here to get to the wineries. He also has to run 60mph up and down a highway for an hour to get to Deadwood. He has a big oil cooler under it with no fan. He has been running it for 5 years now, and averages about 10k miles a year. I just took it apart last winter for a preventative maintenance since it is his money maker each summer. I replaced the P&C set while it was apart, and recut the valve seats. This was at 45k miles. That is about the standard service interval for a valve job on a factory VW engine. I did need to do a line bore on the case because of the crank flex from the huge load. The center main started to get looser than I want. I knew this would be a problem when I built it, but we figured by the time the case needs to be cut a few times, the rest of the bus will have fallen apart around the engine. The next one will get T4 main journals on the crank.
Here is the bullet proof combo I did for the limo bus.
New aluminum bubble top case
84mm crank. VW journals
AA 92 Thick walls, grant cast rings
5.4″ Scat I beams
Web 218, set on 106lc. CB light lifters.
Aluminum push rods
CB CNC panchito’s heads. I swapped the springs to a single with a flat wound inner damper.
40mm IDF’s w/ 34mm vents
Stock flywheel, KEP S2 plate
1 5/8″ header
26mm oil pump
8.7cr, .045″ deck, 63cc chambers, 2cc dish in the pistons.
It starts making power as soon as the clutch is let out, and it’s done at 5200rpm. Peak torque is made right at 4000rpm…just over cruising speed.
A similar engine in John’s bus would be amazing.
So……build it how you want….but take each part into consideration. All parts need to work together within the same power band, and they all need to work together. Take the time to modify some parts if needed. The power is in the heads, and any one wrong part can screw the whole thing. You cant just toss a part into the mix because you used it in the past, or you have it on the shelf. Don’t just use a cam because that’s what everyone is using. Get the combo right, and make sure all the small details are put into the build, and it will live a long, powerful and cool life. An oil temp gauge also helps you get there….. 😉
Its all in the part combo…
BrianJohn JonesKeymasterAugust 11, 2020 at 9:03 amPost count: 6723
Lot of info there… long read. Thanks… I bet I am at almost 20k. Just this year… and some of them miles off-road, Shasta style miles😁😁😁😁😁😁.
It all works… some better and longer, but it all will work.. and as long as I can keep having as much fun as I have been having the last few years in my bus, I will continue to search for the perfect set up for me. My insistence to have stock heater boxes is going to limit me, and I can’t be holding my shit at full throttle and accelerating up hills😁😁😁😁😁😁😬😬😁John JonesKeymasterAugust 11, 2020 at 9:08 amPost count: 6723
A few days back I was feeling pretty good and decided I could sweep up out back and pick it up and put the garbage in cans… BAD idea… that set me back about three days with fairly bad pain with almost every step I took… 😟😟😟😟😟. I finally this morning can walk again!!! Fuck my shit is sensitive right now…Pat KKeymasterAugust 12, 2020 at 12:51 pmPost count: 1413
I’ve only met a hand full people that deserves more rest than you, couple of them are dead.
We will build it if it comes.John JonesKeymasterAugust 19, 2020 at 8:16 amPost count: 6723
Driving the kombi this last trip… was nice!!! I think the straight axle makes a big difference.. and I think the kombi is built more like what Brian E would build.. I know I was traveling light also.. Gretchen mentioned it took a whole nother bus to load up what she used to put on the Pamper roof😁😁😁😁. Zack drove the vanagon subí swapped a Goldie … what a disappointment it still isn’t right and acted overheated all the way home… I drove back from delta in third gear☹️☹️☹️☹️☹️☹️☹️☹️☹️☹️☹️☹️☹️☹️☹️☹️☹️☹️☹️WillyModeratorAugust 19, 2020 at 11:57 amPost count: 1141
Summer heat in Western Colorado is tough on VWs…BBWBParticipantAugust 19, 2020 at 1:13 pmPost count: 839
Summer heat in Western Colorado is tough on VWs…
I’m doing just fine with southern AZ heat. Just did a trip to Ely, NV and back. Over a 100 degrees the whole way there and back. I think something is wrong with Goldie. Wish I had the means to acquire her.
I'm at the age where "fuck off", "fuck you", and "fuck it" answer most questions.RustabusParticipantAugust 20, 2020 at 9:03 amPost count: 1967
Damn!!! Guess some VW’s just gotta fight you the whole time!!!☹️Glad you’re getting out though!!!😀John JonesKeymasterAugust 21, 2020 at 11:23 amPost count: 6723
Oh it’s my fault Rusty… I over load it… I run it too hard and I like to use it like a work truck!!!! 😎 I need to slow down on hills… and learn how to pack a little bit lighter.. 😎 I’m gonna go down to a 2007cc… Thats the combo Steve at Wolfgang has always preached… I am listening now… 😎 😎
I’m like 8 or so maybe even 9 weeks out of surgery now..I am feeling like I want to do something…. But know it’s a bad idea… 😎 I wanna start tinkering with my projects…… My Pamper motor needs to come.. My sand rail is ready for it’s real transmission and a motor…. although I am not sure my back is ready to bounce around in a sand rail.. 😎 Maybe by the time it cools down?? 😎 Dually always needs something. dumb ass cool ass truck. 😎 Oh,, and my kombi needs stripped and the whole process over back like it used to look… 😎 I wanna redo the shitty plastic interior too.. it sucks. 😎 Plastic can’t handle the extreme heat around here!!!! Not much can.. 😎 I want to leave it lowered, but a decent camper interior.. 😎FranzKeymasterAugust 21, 2020 at 8:25 pmPost count: 3630
When do you start rehab? I mean like going to the gym and on walks n’ stuff. Surely your doc is going to want you to do that before starting hard work again.
We can get the bus engine out and Blaine on the turbo prep.John JonesKeymasterAugust 22, 2020 at 8:30 amPost count: 6723
I have a doctors appt Wednesday so I will ask. I’m feeling pretty good… I did a lot of sitting around yesterday, so I feel great this morning… I can almost get out of a chair without tightening up my whole torso👍🏻👍🏻👍🏻👍🏻
My 2007 is done at painters and kangaroo called.. I noticed there is a pair of 36 dellorto’s sitting all lonely out in a bus.. I think I am going to enforce a “storage fee” and use them… that’s the perfect carb for “project 2007”….😀😀😀😀😀
2332turbo for the sand rail!!!😀FranzKeymasterAugust 22, 2020 at 9:30 amPost count: 3630
Yeah, I think Will owes us all a pain in the ass fee. 🤑John JonesKeymasterAugust 24, 2020 at 9:23 amPost count: 6723FranzKeymasterAugust 24, 2020 at 11:01 amPost count: 3630
If I know you, you’ll be bent over trying to block sand rockers and lift 100 pound sand bags today. 😉
Take it easy for a while longer. We can help you do stuff.Pat KKeymasterAugust 24, 2020 at 11:30 amPost count: 1413
Yeah, I think Will owes us all a pain in the ass fee. 🤑
AMEN to that!!!!! 😎 I feel dangerously good today!!!!!! I can walk without pain!! WHAT!!!! I haven’t felt this good in like 8 years or so…. 😎 😎 I’m feeling like kicking some ass…. 😎 😎
Take it easy bro! I don’t know anyone who deserves it more!
We will build it if it comes.RustabusParticipantAugust 24, 2020 at 12:04 pmPost count: 1967
Slow down Jones!!! No KCW work!!! Take that Lady of yours out to lunch in Palisade and RELAX!!!!😀CorporateModeratorAugust 25, 2020 at 1:55 pmPost count: 863
Yay!!!! New motor for the Pamper🥳🥳🥳🥳🥳🥳🥳🥳🥳🥳
I love going on adventures in our bus!!!ColeBModeratorAugust 26, 2020 at 11:59 amPost count: 1649
oil cooler the issue?
your new 36 hp Motor will last a lot longer than that damn 2332😘John JonesKeymasterAugust 26, 2020 at 4:58 pmPost count: 6723
It looked like it was leaking from the cooler… but hard to tell… I threw the bitch in the trash and went out in the trailer and grabbed and GERMAN made oil cooler…. 😎 😎 It should get warm enough during break in to show many any leaks… 😎 we got some zinc add and 30weight…
Bam, out with the old, in with new!!! and….. it’s about to time to break it in…. 😎 New 2007, stock heads this time…. w100 cam, 36dells…. 😎 8.5 compr… simple motor.. 😎 reused alot of my stuff , now 2332 will be rebuilt for sand rail!!!!!!!!!!
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