Puzzling combination of Type IV issues - it runs this advanced?

[orwell84]

[skills@eurocarsplus]

[Squeeze Cheese]

Orwell, does your engine have a lopey idle?

I’ll be interested to hear how Jmstu does with this 107i cam. Len and I did chat about your engine. Why was the choice made to go with flat topped pistons on a 2.0 with a higher lift cam? I would think your valve to piston clearance would be really tight.

How does it sound at idle with that complete 75-78 exhaust you have? I converted to the 72-74 but it’s no quieter. Better interior heat though!
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63' Ragtop Beetle

78' Dakota Beige Westy. “Skills” EJ25 engine conversion w/ zero mile factory short block, Delta 1000 cams, heater core and modified Gilmore AC. Matt Steedle 091 transaxle upgrade w/ 4.14 ring and pinion, Folts aluminum gear carrier. General Grabber AT2s on stock wheels. Solar powered aux battery w/ inverter.

[raygreenwood]

[orwell84]

I’m glad you got it mostly sorted out. When I chose the Web 73, I thought of it as a very conservative deviation from stock and at worst would not give me any noticeable performance gain. I kept my CR low thinking erring on the low side would keep temps down even if I didn’t get all the good out of the cam. I am happy with the improvements with my bus, though they are modest and it difficult to tell whether it is the cam or replacing my garbage heads with Len’s. I have since realized that my knowledge of this had some serious gaps and the fact that my engine runs decently is because I was more lucky than good.

[Squeeze Cheese]

In conclusion...

I had Len flycut the heads to get me up to 8.0:1 CR, right in the middle of the suggested range for that 107i cam, and reassembled. Thanks for doing that, Len! It seemed to be the fix.

During the course of a few weeks of tweaking, I’ve achieved a pretty strong and good running engine. I found that it “likes” the timing at 34 BTDC max advance hoses off. There’s no pinging and it pulls better than before when it was bone stock. Decent low end, but with a noticeable power band from about 3200-5000RPMs, although I usually shift at 4500. It’s a fast bus around town, the fastest air cooled powered bay I’ve driven. I’m able to easily pass on level ground and maintain speed up hills in fourth that I was having to downshift on before. And it’s running cooler than before. I’m only at around 360-370F CHT at 65MPH in 90F ambient, even with the AC cranked.

Still, in hindsight I would've stayed with the stock cam and the reason is the idle. It’s lopey and that’s just how it is. At 900 RPMs it sounds like my dad’s old panhead. It might sound cool to some but I’ve learned that I prefer the quieter steady purr at stoplights. I’d give up a little performance for a better idle. But, I compromise by setting the idle to 1100RPMs which smooths it out a lot.

Next I have some AFM adjustments. The setting I used when it was stock is now running a bit rich. I’m only getting 14MPG mixed driving. Since I have some CHT to spare, I’ll be hooking up my LM2 and try leaning it out till I find a happy place between good MPG and cool enough CHT.

Hope that helps!
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63' Ragtop Beetle

78' Dakota Beige Westy. “Skills” EJ25 engine conversion w/ zero mile factory short block, Delta 1000 cams, heater core and modified Gilmore AC. Matt Steedle 091 transaxle upgrade w/ 4.14 ring and pinion, Folts aluminum gear carrier. General Grabber AT2s on stock wheels. Solar powered aux battery w/ inverter.

[orwell84]

[skills@eurocarsplus]

[jmstu76]

[skills@eurocarsplus]

[skills@eurocarsplus]

interesting that you guys are having similar results.

wonder if web cam has fucked up the final grind? guess all you can do is compare with a stock and see where they went wrong, or this cam is just a no-no for this application.

not knowing the #'s off the top of my head... .060 deck is huge imho. I usually run .040 and adjust c/r in the heads.

my 1904 (granted, it's a T1) pulls really nice in a westy. .040 deck and 8.1 compression. iirc, 64cc chambers. any time I have pulled apart an engine with huge deck, I just kind of laugh.

nothing like doing a job twice...
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[jmstu76]

SO...

I also just built an FI type IV.

stock case
Stock throw crank (71mm) counter weighted
Stock length rods (H beams) using type IV bearings
96mm KB flat top (no dish) pistons
Hoffman stock heads (not camper specials) with the coatings
Webcam 107i cam and webcam hydro lifters
bone stock FI with new geebee silicone hoses
'76 stock exhaust, F pipes, U pipes, boxes, Crossover, J pipe, cat delete, Muffler and tail pipe. (all previously ceramic coated)

When I was going to set the deck height, Len warned me of a customer running the same cam and the CR was too low, He wanted to flycut my heads. I explained that I was using flattop pistons. I was shooting for a CR of 8.5/1. This called for a .050 shim at the base of the cylinder. Since no-one makes a .050 shim, I opted for a .060 giving me a little lower CR.

I had set my Throttle body bypass screw the same as the previous engine which was bone stock everything. 2.5 screws out from all the way in.

Well guess what happened at first start up?

it fired right up after getting positive oil pressure. now I immediately went to unscrew the by pass screw to raise the rpms to break the cam in.

No change, so we rigged the gas pedal to hold the rpms for 25 minutes of cam break in.

After cam break in, I set the timing at 28 degrees btdc at 3k rpm with hose off and plugged.

it ran super smooth and quiet but had NO low end power (sound familiar...)

Then I found this thread. Len never told me who was having this problem btw.

I sure wish I would have researched that cam more. I tried to buy the very best but I feel like maybe I was mislead. I bought directly from Webcam because other online suppliers wouldn't give me a date when it would be "in stock"

So I should have the required CR to run it. I did bump my timing up to 34-36 degrees btdc. It runs good with no pinging that I can detect.

The thing is, I only have barely 200 miles on this engine. I'm sure the rings are fully seated.

So I can assume the CR will rise as the rings seat and I need to be careful not to over advance the timing with higher CR.

I wish you luck with your remedy. I hope this combo ends up working for me.

So I have build a 2056. My friend built a 2182 with a 78 mm cam, torque special cam and dual webbers. The thing pulls like a train. So much low end....
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James

'76 Deluxe Sage Green Westy
2258 cc GD case 78mm CW crank, 2.0 H-beam rods 5,325” 22mm pin, JE forged pistons with 15cc dish, JE rings, type 11 clearanced oil pump, CB Eagle 2205 Type-2 “Torque Special” hydraulic cam with matched lifters fed by CB Dual Weber 40 IDF MX with 6” foam air filters, currently 55 idle, 130 main, 200 air correction, 32 mm venturis. 27in General Grabber AT2 All Terrains, Berg Shifter, stock '76 exhaust HPC Ceramic Coated. 11/18/2020

[raygreenwood]

[Clatter]

Don't fly-cut type 4 heads if you can avoid it.
They need the meat/support, and the exhaust studs lurk right below the seating surfaces.
You want as many opportunities to surface the heads in the future as you can.

Remove base shims, or shorten cylinders.
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Bus Motor Build

I have excellent news for the world...
There is no such thing as patina.
It does not exist!

[Clatter]

I'm of the opinion that you might just have something simple going on.

Even plastic timing scales can be a few degrees off.. Sometimes 4-5-6 degrees.

When you are checking for TDC by sticking something down the plug hole,
it might not be that accurate as well.

Are you -sure- you are 100% accurate in your TDC measurement?



Give the motor what it wants.

Some of the best builders might tune by 'ear'.
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Bus Motor Build

I have excellent news for the world...
There is no such thing as patina.
It does not exist!

[Squeeze Cheese]

[Amskeptic]

[Amskeptic]

[raygreenwood]

[skills@eurocarsplus]

Vanagon=different animal....

77 bus...carbs or FI? you'll never know the build specs. I feel for you steve, really. sucky situation for sure. but as you see by my photos, a well cared for but used 2.0 had almost (almost) twice the compression you have....

compression isn't a dirty word when done right. iirc I am running a tight (.040) deck on my 1904....different animal for sure...

bring it up. I have 2 swaps going on now, what's another

no joke...dumpy busses owners just got back from TN. it hasn't had an oil change since I built it in '16....that is the God's honest truth. I talk to the owners all the time....I haven't been under the bus since the build
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