[leec4391]

Hello,

I am currently preparing a d16y3 (read d16a6 with z6 head gasket) for an engine swap. I bought a delta 272 cam as an upgrade as they're relatively cheap and meant to be pretty good.

Now i've got an adjustable cam gear and went about degreeing it in today using the following cam card(as most know delta don't seem to supply them with their cams which is odd);

Now that cam card states that at .050 of lift(opening and intake) the cam should sit at 4.5BTDC of which it does now after some minor fettling, it also closes at the correct crank angle 32 degrees ABDC.

How ever i proceeded to measure the lift at .050 intervals like the cam card to check the specs of the cam and after 0.050 it all went a bit tits up. My findings went as follows;

intake cam opening(BTDC);
0.100 - -12.5
0.150 - -25.5
0.200 - -38

Intake cam closing(ABDC);
0.100 - +16.5
0.150 - +5
0.200 - -6

They are way off what the cam card says it should be as the lift gets higher the gap gets bigger. Also the lift measured from the top of the retainer was measured at 0.361" when it should be 0.394" according to the cam card.

The exhaust was even worse, it didn't even match up a 0.050" which i can't adjust as according to the intake side its zeroed.

Exhaust opening (BBDC);
0.040" - +46.5
0.050" - +36
0.100" - +23
0.150" - +12
0.200" - +1

Exhaust closing(ATDC) sorry i only have from 0.006"-0.050" of lift.
0.006" - +2
0.015" - +0.5
0.020" - -7
0.040" - -14
0.050" - -17

Now the exhaust closing isn't too bad(in comparison to opening) with specs being only approximately 3 degrees out. But opening at .050" is almost 14 degrees out from what the cam card says it should be.

Also i measured the lift to be .380 - 0.010" more than stated on the cam card.

This was my first time degreeing a cam but i have done lots of research towards the subject. TDC was found using a piston stop and valve lash was set to zero.

Now can anyone explain why my results are so far from what the cam card says they should be?

Bad regrind?, maybe im doing something wrong? The dti was put on top of the retainer ensuring it was at the same(or as close to) the angle of the valve.

Any info would be great,

Lee

 

[TheToaster]

Delta Cam is Fucking Stupid, and their Products are Shit.

Old Dog using Old Tricks

He uses an ancient ford grinder and claims to copy profiles

The place is a gimmick, makes your car run like shit so you think its faster

He doesn't even know what he's doing with modern cars

Just making money and designing cams like it was the 70s.

They love making money off of people looking for the cheapest product where the standard is low. You get what you pay for. Widely used, does not mean good.

Find someone that cares about how the engine runs.

 

[leec4391]

So are you saying it's a bad grind?

As most of that post was a huge rant.

 

[transzex]

You are using an example cam card from 7.5 years ago?

Jon is on the FB page, I just approved him the other night.

 

[leec4391]

This I'm aware of but it's all I've got.

Plus I don't know how old the cam is I bought from a member on here last year, and he never used it himself.

Jon from delta? Also I assume you mean the d series .org page? As I am not a member, will sign up now.

 

[transzex]

Approved....

 

[leec4391]

Cheers bone. I spoke to Jon and this is the response I got...

"The cam card is produced by computer with only 2 points of measure. Lift and rotationThen those 2 gauge readings are computed and a theoretical card with data is printed. The most accurate is to degree it in your engine, with proper lash."

I then asked how the cam card being computer generated affected my findings.

"No not ignorant at all..... the specs in duration are measured in crankshaft degrees, .002 milled off block deck and the numbers are no longer 100% accurate"

"Same if head is surfaced or aftermarket gasket is used, anything to move the cam centerline in relation to crankshaft centerline will throw numbers off"

"You are checking it correctly by the .050 lift to .050 close method and that's set for .006 int, .008 exh. All of our regrinds are done at factory 0 to maintain base circle material. For every degree we " move " a lobe is generally .020 material removal just for stock grind"

"0 lash will give over all duration, but I prefer to know exactly what specs are in running condition, so when I'm building my race engines I check at lash."

So as of yet I'm still none the wiser as to how I should properly degree this cam shaft. I need to do some more research to find out how to degree a cam shaft when you have no cam card.

 

[TheToaster]

Watch the Ledge develop where the untreated metal meet the OEM surface.

Try to tune, and adjust lash for that. Worse than a pitting cam.

 

[transzex]

Install cam straight up, adjust cam gear, readjusting base ignition timing as well to get desired powerband.....

I tend not to overthink things

 

[leec4391]

That is the way its going to pan out by the sound of things bone.

I just wanted to learn a new skill that will help later on in this build or others. Unfortunately it hasn't worked out so well.

I always planned to go for a more aggressive cam from 'Cat cams' as it is so maybe i'll have better luck next time.

 

[88cr-rex]

My 272 is the exact same . . . numbers were close-ish to the cam card.

Definitely some "room for error" over there at Delta.

I was building my dragster motor at the same time as my SOHC zc hodge podge and it was rather funny to me to have a gear drive setup in a 1950s designed engine be dead nuts on the cam card with a simple dot to dot lineup and be not even close with a "modern" engine, belt drive, adjustable gear, etc.

Spent 2 minutes on the sbc and 20 minutes playing around with the zc

 

[buzzbomb]

my 272 came with a cam card, maybe I should complain.

 

[leec4391]

Buzzbomb any chance you could take a picture of it or scan it and post it up?

It would be of great help, even if its just to see if its the same as the one i used.

Also did you dial yours in? Using the cam card.

 

[buzzbomb]

Buzzbomb any chance you could take a picture of it or scan it and post it up?

I took a pic when I got it, I'll see if I can dig it up.

Also did you dial yours in? Using the cam card.

lol, no, just dropped it in with the stock cam gear.
gave it a street tune, with ebay header, intake and 2.25 exhaust.
took a whole second off the 1000' mark (maybe it was my t00nh34r: )


edit:
I remember there was a big stink about Bisi not giving his customers card for his cams but Jon was always forthcoming. Talking to him on the phone was the best way to communicate with him.

 

[leec4391]

If you could find that pic that'd be great bro!

I'm running carbs and vac advance dizzy so tuning fuel there will be no problem i may be some what limited to tuning ignition but it is adjustable.

Only problem with calling jon is i'm in the UK and its would cost alot to call internationally. I did contact him over facebook, but i'm still none the wiser to be honest.

 

[TheToaster]

Jon is forthcoming with quantity

but not quality.

Easily impressed.

 

[HiProfile]

What is the purpose of degreeing the cam? Making it agree with some numbers on a piece of paper?

Honestly I'd rather have a different set of numbers as my goal - meaning I place more value on where the cam makes the best powerband on the dyno. Degreeing is crucial for DOHC's in finding "zero" and what various adv/retard angles provide clearance issues. For a SOHC get the lobe centerlines close, tune it halfway decent, then play with cam angles. Pick your powerband then fine-tune the maps.

Toaster I don't see people bitching about Honda's shitty quality when the stock motor they boosted blows up. The 272-2 is just too aggressive for anything besides a few dozen sprints down the track. Meanwhile the 260 & 272 grinds have been used in several dozen motors, if not hundreds, w/o issue. I won't defend their noted quality issues, but they will also take care of customers when the customer comes to them. That's uncommon even for cams that cost 5x as much.

One more thing, most are also being installed by amateurs. Wrenching on a car is like sex, most guys thing they're great at it.

 

[buzzbomb]

hope that helps

 

[leec4391]

What is the purpose of degreeing the cam? Making it agree with some numbers on a piece of paper?

Honestly I'd rather have a different set of numbers as my goal - meaning I place more value on where the cam makes the best powerband on the dyno. Degreeing is crucial for DOHC's in finding "zero" and what various adv/retard angles provide clearance issues. For a SOHC get the lobe centerlines close, tune it halfway decent, then play with cam angles. Pick your powerband then fine-tune the maps.

I did think of it like that, as i remember a thread where someone was asking if degreeing a D series cam is really necessary when you only go and change it on the dyno to tune the power band anyway.

Honestly i did it more to learn a new skill, not so much because i thought it was necessary. Lets be honest it was inevitable that i was gunna run it anyway, and thats exactly what i've done. Got the engine firing yesterday afternoon, let it sit at 2K rpm for 15 minutes while the coolant bled and i've been beating on it since.

Feels great a pulls well, its light years ahead of my d14 with an a6 cam.

Also buzz bomb i appreciate you searching for the cam card but it says it for a Vtec, i shall rep you(if i can), Thanks man.

Lee.

 

[Custom Import Heads]

Toaster,
your constant rant about our quality shows your not a rational person and people like you give the " Honda" crowd a bad name. Your received 100% refund because I couldn't resolve your issue. The cam card posted by Buzz is for a SOHC Vtec different head series. Im headed back to the shop and will post a picture of the computer used to read specs off cams. As stated, the computer reads lift & rotation only, then drops the info into the hard drive and generates theoretical duration, and open and closing events, all of which are measured in crankshaft degrees which clearly I don't have hooked to computer. ANY REAL ENGINE BUILDER KNOWS THE ONLY TRUE SPECS ARE WHEN THE ENGINE IS ASSEMBLED AND DEGREED. Camshaft centerline to Crankshaft centerline will vary with milling, decking, aftermarket head gasket, none of which can be " computed " with any accuracy. Degreeing this build set cam gear at zero and get your specs.