Camshaft grinds for turbo

[70dragbug]

Me too Wally!

[930]

Hello,

Sorry for bumping up an old thread...

I've read pretty much the whole topic and I would like to get Your opinion / advise on cam selection for the following engine. If possible I would like to stick with normal "off the shelf" cams i.e. no special grinds etc.

*69 C/W crank (stock welded)

* 88mm thick wall AA P&C set (Hypereutic). Stock balanced rods. Whole rotating assembly has been balanced.

* 043 heads. Ported with stock valves. 36cc chambers, deck height 1.5mm = 10.3:1 compression

* Single 60mm TB and 4 x 440cc injectors

* Speeduino DIY ECU

* RE85 fuel

* No intercooler / no water or meth injection

* GT2860RS Disco Potato Turbo.

I am aiming for 0.8-1.0 bar boost max with around 150hp.

The plan is to make an affordable engine which would not grenade instantly. Hence I am sticking with hypereutic pistons as the cost creeps easily when going with bigger forged pistons. Some say hypereutics are fine with moderate boost, some that they will grenade

Any other recommendations are also welcome - even though this thread is focused on cam selection.

Thanks a lot in advance for Your time helping me out.

[Wally]

As for a usuable cam, i'd say anything regular between 250 and 260 degrees @ 0.050" opening reference will work well (iirc a 86b is about 260 degrees).

[Dan Dryden]

The 10.3:1 compression is quite high, especially as you're not using forged pistons. With an 86b cam, I would aim for around 8.5 - 9:1 compression.
The throttle body may be a little large too. A 52mm would probably give better driveability.
To run the boost pressures you're planning I would recommend some kind of charge cooling.

[madmike]

CR is High , but not for E85
W100-W110 or a even a k8

[930]

Thanks for the replies so far, appreciate it.

I don't want to run too big of a deck so adding shims under cylinders is out of the question. I could add copper shims under the cylinders though or I could reshape the chambers a little to lower compression - if that is needed. RE85 is pretty forgiving though?

I do have a small air-air intercooler from a Lancia Delta but I thought to keep this install simple and to avoid any "unnecessary" ducting / fabrication. Based on input provided here and TB size calculators TB is a bit too big for my application - as I got it cheap I'll run it and worry about changing it later

I checked 86b and aircooled.net has it available with 112 lobe centers for a pretty small fee - should I opt for this or just get a W110 with 108 LC and call it a day and see how it runs? I'd rather get a decent cam the 1st time as changing requires a bit of work

Keep hints and suggestions coming. I don't intend to hijack this thread so send me a PM to avoid polluting this excellent thread. I'll start a build thread of my own pretty soon though.

Thanks again!

[Clonebug]

I'm running a W-100 cam with stock 1.1:1 rockers, solid shafts and single HD springs.

With my turbo setup it will pull hard to the self imposed redline of 5200 rpm and I have had it to 5800 accidentally.
At 5800 it maxed out my 32# injectors at 95.3 percent. It is still pulling hard and I am sure that is where I will gain the hp if I rev it higher.
My injectors will support 230 hp at 100% so the power potential is there.

I have a set of 45# injectors hanging on the wall in my garage to install this winter.

I am running a stock German FI TB at 45mm and it has great throttle response. I used the German plenum for one season and was not impressed with the throttle feel. The linkage made it really sticky and it was either on or off.
Check my build... I built my own intake out of I think 1 3/4 inch tubing. It was the largest that would fit under the alternator mount without making it a PITA to install or remove.

[petew]

Sorry, if this is slightly off topic... but I'd plan for an intercooler of some sort if it's a road car.

I've to a stock 1600 with an Engle TCS-10. Like a 110 but with less overlap. Works well, but I'm no expert.

[GARRICK.CLARK]

Hi guys.
Can someone do me a favour.
I'm using a web 86A cam on my turbo type 4.
I'm getting either intake backfire
or exhaust after fire.
Is the spec of my cam wrong for turbo use.
Thanks for any advice.

[woodsbuggy1]

Your problem is not the cam, check timing, AFR, basic tuning.
Good Luck
Kenric

[Piledriver]

Mr. Clark is still "tuning" sans Wideband O2 sensor, which means "I'm guessing" at the AFR.
Hopefully Santa will bring him one for Christmas, an SLC-Free is only $35 from 14point7.com
(The sensor costs more) PLUS it can read/display sensor temperature for a sanity check.
Lots cheaper than pistons/jugs and heads, (if you are lucky.)
A dropped exhaust valve can reduce it ~all to scrap metal in a few milliseconds.

Webcam nitrides their cams, AFAIK no other aftermarket VW cams are nitrided.
The stock cams are IIRC induction hardened, which works for mass production.

Thats the extra $ for a Webcam.
(Google for why you really want that)

[advinnie]

Hi all I’m sorry for bringing an old thread back to life
I’m running a 1600 draw through turbo set up in my bug with a stock crank so my max rpm limit is 5000rpm, the cam I’m using is a engle 100 with signal HD springs and stock push rods. Now my questions to you lot are are should I run 1.1:1 bolt up rockers or 1.25:1 rockers?
Second should I use the stock push rods or the steel ones I have ?

[madmike]

I doubt it will make any difference
are you having issues with the clips breaking on the rockers?
If so, then swap them out for bolted shafts and Yea I'd run the chromoly push rods
and you do know u will have to set up the rocker
"Geometry"

[woodsbuggy1]

Great to see this brought back to life, look at what the experienced guys are using not so much what the "experts" recommend. If you like a cam NA, then you will absolutely love it with boost! . I am not at all claiming to be experienced or an expert, but I have learned what advice to listen to. Thanks for all of the great info.
Kenric

[madmike]

Yea I've always been a small cam guy (w110-w120) never tried anything big until I was talking to a few guys and the fastest guy east of the mississippi told me: "just try it 'You'll like it" spot on Mikey like's it (FK 10)