Cam timing Part 2, wierd "stock" T4 cam, JAKE??? Anyone??? too high of lift??? Options

[Mark Henry]

This is my last post on Dylan's original thread, he thought that he installed a NOS VW/Porsche cam in his new rebuild....

Dylan's getting .330 lift at the cam. I measured a new Web 73 and I get .320 lift
On the stock (used) cams I have I get about .275 at the cam, even less for a hydro.

It does have a rivet on gear and I’ve never heard of an aftermarket cam with a rivet on.

I’m at a total loss on this puppy. I’d hate to have Dylan rip out an OK cam, but things smell real fishy.

This cam has me going WTF! (IMG:style_emoticons/default/unsure.gif)

Is it a hipo regrind on a stock cam?
His new engine with stock FI will not idle below 1500rpm

You can read the original thread here:

http://www.914world.com/bbs2/index.php?act...=ST&f=2&t=14964

[F4i]

Measured more accuratly It's .320 at the end of the pushrod. It did have a stock riveted gear.

[F4i]

912 cam? Euro carb motor cam? A metric speedo came with the parts lot I got the cam with.

[F4i]

More specs on the mystery cam. This is measured to the best of my ability.

Gap @ .040
intake opens 20 BTDC
lobe center 106 ATDC
intake closes 52 ABDC

exhaust opens 53 BBDC
lobe center 73 ABDC
exhaust closes 14 ATDC

Lobe centers shold be very accurate.

Lobe lift at the pushrod is about .317
With the adjuster screwed in ti just touch the valve (no clearence) I got a lift of .411

So that leaves me totally confused as to what cam this is. It does go a long way in explaining why i cannot get the sucker to idle. Help??? Jake?? Anybody??
(IMG:style_emoticons/default/idea.gif)

[Brad Roberts]

I know of at least 3 places that hard weld cams (with the stock gear in place) I'm betting it is a Elgin cam. Any weird numbers on it ? (on the end with the gear..hand scribed with a etcher) ??



B

[Brett W]

Here are the specs based on the info you have given me.

Overlap: 34.00 degrees
Intake Duration: 252.00 degrees
Exhaust Duration: 247.00 degrees
Intake Installed Centerline of 106.00 degrees ATDC.
Exhaust Installed Centerline of 109.50 degrees BTDC.

Look on the flange end of the camshaft and see what it says. In my opinion not the best cam to be running in a stock T4 with out extensive head work Way too much for Dject.

[F4i]

Its still in the engine. I can pull the oil pump and have a look. Question is will this work? And will it work with the stock injection? If not should I 1. Make it work with aftermarket FI or 2 Replace. I do appriciate any help. I have been fighting this for weeks now.

[seanery]

Cam and lifters about $300. Cheap enough insurance for me.

[F4i]

Have the lifter issues been resolved? Plus if its a good cam I don't have to tear down the engine. And I can convince the wife I NEED Kits or SDS. The smart money is a new cam though if the lifter problem is resolved.

[F4i]

Going by what brett is saying (thanks for doing the math on it) this cam won't work without some head work. As well as carbs or new FI Correct?

[Mark Henry]

Anyway you look at it, there is no easy or cheap solution to your problem.

Cam and lifters... Ceramics are the only way to go at this moment. Unfortunately the supplier is very slow, Charles (LN) is now getting a trickle of them in, but you will be on a waiting list with at least 30+ sets ahead of you. You would have to email Charles to confirm the wait time.
You have had the engine running, so I would take the lifters out (keep them in order) and look for wear, just to be safe. Do this before before you spend the coin on the SDS.

Carbs may have an issue without headwork, but in my junkyard 2.0 engine with a scat cam that has .430" x 276 Degrees, SDS had no problem running it. The only real head issue would be how long will the stock springs last if you start honking on it.

If you did go for SDS here are the main issues,

1/For FI only (D system) you will have to upgrade your dizzy eventually.

2/For FI/MSD (E system) It's programmable ignition, but you need the MSD box/dizzy.

3/For the FI w/Crankfire (F system) the engine must come out, fan shroud off and you must custom fab the trigger mount.

The "D" system can be installed in a weekend, the "F" might take 3 weekends. I already know Dylan has access to the equipment needed for the install and the more he could do at work, the less time on an "E" install. These times will not be a "squared away" install but it would have you up and running. I can help you a bit if you do go with the SDS system.

The Kit Carlson system is still 4-6months away from production.

[Rusty]

Well...

[F4i]

Lawrence The bunny is just what I need right now. (IMG:style_emoticons/default/laugh.gif) Thanks.

Mark You brought up a good piont on the springs. With that much lift it must be killer on them. I would be looking at possible valve float or just breakage. What springs are you running? You are correct in assuming I could hook up SDS in a short period of time. The resources are in place for that: I have a shop at my disposal, SDS is down the street, I know somebody who has made it work (you). Is it correct that it tunes as you drive with a built in mixture moniter?

Megasquirt and spark could be an option as well. I am not an EE but can figure out most things electrical. I do not have easy access to a scope however. Any of you guys who have done it have any input? Build time? Hapiness with the system? I understand dyno tuning would be a must.

I thought Jake had another lifter solution. Anybody know? Is this cam worth the effort? I don't know what this setup will yield. I may be throwing power away. Moving the power band up too high? I am not familiar enough with the dynamics of this motor to tell. Any insight here would be helpfull.

Thanks for all the help guys. Special thanks to Mark for talking me down off the roof. (IMG:style_emoticons/default/laugh.gif) Sorry for the long post.

[Mark Henry]

I'm just running HD single springs, my engine is totally low-budget, I'm spending the big coin on my 2.6 nickies engine.

SDS does not tune itself!
It will come programmed roughly in the right direction, but you will have to fine-tune it yourself. One man can tune as they drive, as it has a very simple controller. You will need a lot of open road to do it this way. I had mine programmed pretty good in 2-3 hours.
A rolling road dyno would most likely be faster to program. Once programmed you can lock it down and remove the controller. If you were to get it done on a RR dyno (couple of shops in Calgary), you don't really need an A/F meter as the dyno shop will have a WB unit, but they're nice to have.

Mega squirt will have more build/install time and dyno time is a must.

Jake's first lifters have failed and they have gone back to the drawing board, no ETA on them at all. His lifter were going to be $350 vs. $450 for the ceramics.

No idea on the cam, it's hipo, but it's also an unknown. My scat cam has the same lift, but more duration and it seems to run OK. The SDS will run it, but how good is the big question. I would take out the pump and see if there is a number on the end of the cam.

[F4i]

Sorry I didn't mean SDS tunes itself. I meant you tune it as you drive. Sounds like thats correct. Sucks about Jakes lifters. I will pull the pump and see what I can see. You are using standard HD VW springs? I think I can get these at the local VW shop.