Type IV rebuild / refresh thread. Nothing ground breaking., Changing cam in low mileage rebuit 1.8, making it a little hotter! Oh yea! Options

[Mark Henry]

Don't used straight cut gears, my great big engine in the bug still uses a stock gear.
You can reuse the gear but you have to face the holes and sink them a bit to clear the pump, but really a new gear is only something like $30.

Use the extra thrust bearing on the cam. BTW type 1 and 4 use the same thrust bearing.

[DavidSweden]

Use the extra thrust bearing on the cam. BTW type 1 and 4 use the same thrust bearing.

Extra thrust bearing? Please explain

[Mueller]

Don't used straight cut gears, my great big engine in the bug still uses a stock gear.
You can reuse the gear but you have to face the holes and sink them a bit to clear the pump, but really a new gear is only something like $30.

Use the extra thrust bearing on the cam. BTW type 1 and 4 use the same thrust bearing.

Thanks, I'll do more shopping around.

^ditto on "extra bearing" (IMG:style_emoticons/default/blink.gif)

thanks

[Tbrown4x4]

Only 1 half of a cam bearing has a thrust surface. You buy two cam bearing kits and use two thrust bearings to increase thrust surface area.

[Mark Henry]

On the double thrust cam bearing couple ways to go about it:

1/Buy a 2nd set of T4 bearing use the DT and toss the rest.
2/Same thing with T1, same bearing as T4, but you can get a DT set that has two DT and save the 2nd DT bearing for later.

3/ buy a set of porsche /6 intermediate shaft DT bearings, they are the same but the oil hole is in the wrong place. So make sure you use one T4 with the correct hole and the other half can be the /6 DT. You could drill the /6 bearing and use both, but I've never done that

Sometimes you have to mod the bearing by filing off the lock tang, the lock tang isn't needed, I've never seen a spun cam bearing.

[Mueller]

Looked at the bearings I took out of the motor, makes sense now.

Only one shell has the thrust surfaces, middle bottom shell.

Bearings not shown in assembly order, the pair that has one thrust bearing surface is the 1st bearing in the motor. The middle is a tad narrower than the rear bearing.

[Mark Henry]

If that used DT bearing has a copper face and is in spec you can reuse it for your 2nd DT half.

[Mueller]

If that used DT bearing has a copper face and is in spec you can reuse it for your 2nd DT half.

Yes on the copper face and all the bearings and surfaces look perfect, but I'll still measure here and there.

[914werke]

Do I have to buy a new gear for the cam or can I remove the rivets on the original cam and the use bolts?

I saw a straight cut gear in the classifieds....too loud?

What about cutting a groove in it?

And if I do use my original cam gear worth making it adjustable able?

I also was curious about a straight cut cam gear. I happen to have one (IMG:style_emoticons/default/confused24.gif)
Whats the advantage, if any?

Also as Mike queried anyone made an adjustable gear to index the cam in the eng?

[McMark]

Do I have to buy a new gear for the cam or can I remove the rivets on the original cam and the use bolts?

I saw a straight cut gear in the classifieds....too loud?

What about cutting a groove in it?

And if I do use my original cam gear worth making it adjustable able?

I also was curious about a straight cut cam gear. I happen to have one (IMG:style_emoticons/default/confused24.gif)
Whats the advantage, if any?

Also as Mike queried anyone made an adjustable gear to index the cam in the eng?

Straight cut cam gears are much louder, but take less HP to turn. The helical gears on a stock cam gear keep some tension on the system (hence the thrust bearing) as well as ease the contact between teeth by gradually bringin them together.

There are adjustable gears available as well. But from what I've heard they can lose adjustment or go loose. If I wanted an 'adjustable' cam gear, I would buy one of the cheap ones, find the timing I wanted, and then index a regular cam gear to that new location.

[colingreene]

I have a straight cut cam gear, its not honestly all that loud.

[Mueller]

I have a straight cut cam gear, its not honestly all that loud.

thanks, I've watched a few youtube videos and with rest of the Type IV engine sound (mechanical, intake and exhaust) the cam gear doesn't seem that bad.

Makes it sound a little more /6 engine'ish (IMG:style_emoticons/default/smile.gif)

[Mueller]

Still trying to find some input on whether or not the stock L-Jet will work with this 9600 RAT camshaft? (IMG:style_emoticons/default/smile.gif)

Dual Webers are calling my name, trying to avoid spending the $$$ and joining the darkside.

[McMark]

Induction is easy to change. Run the L-Jet and see what happens. (IMG:style_emoticons/default/tongue.gif)

[Mike Bellis]

Run the L Jet and put a piggy back system or full ECU swap on it.

[colingreene]

the right and best way to do modern ish fuel injection on the cheap would probably be Megasquirt.

[Mueller]

the right and best way to do modern ish fuel injection on the cheap would probably be Megasquirt.

Just nervous with a fresh rebuild, what if it doesn't start right away or stalls too often?

Will I screw up my new cam if it takes too long to get it running longer than 20 minutes or so?

[colingreene]

You might want to talk to Mark on here about it, or read through some of the builds using it.
Worst case start it and run it on a carb to break the cam in.

[McMark]

The cam assembly lube sticks around for awhile. And if you run closed loop and autotune you can get it to rev to 2000-3000 pretty easily and be sure you're not flooding the motor.

With no load on the engine, your mixture and timing isn't nearly as critical. So you run the engine, rev it up, keep an eye on the mixture, but keep it running/rev'd until the cam break in is over. Then move your attention to tuning.

Also, this is the part where I praise the gospel of dyno tuning. Pay the money. Get it done first, not last. It's worth every penny.

[jim_hoyland]

Any updates Mike ? I am looking at upgrading my L-Jet as well. Currently, it has the 94mm pistors and 2L crank shaft. I have a set of stock heads that are resurfaced and and new valves added- no mods though.

My local indy is going to replace the heads and suggested adding 96mm pistons. Since you drove my car at the WCR 2015 at San Simeon, I thought you might have some useful suggestions. And. it hasn't pinged again... (IMG:style_emoticons/default/smile.gif)

Gonna stay L-Jet