On stock rockers?

 

Stock rockers? Can't run those with this cam either. This is standard max preload for the LE/BRE cams.

 

I meant on stock lifters... sorry for confusion. Stock lifters require 1/4-3/4 turn preload.

 

Even they will work best with as little as possible.

Bret

 

I went 1/2 turn on mine.

 

I am sorry that you are having problems with the stuff you got from me but as everyone else has said i am sure that the problems don't lie in either the heads or cam. I gave you the Fel Pro gaskets with the heads but recomended the Mr.Gasket 5716's instead with the stock bottom end. I would imagine that the other supporting mods you are lacking and the low CR and DCR, and any other bugs that havent been worked out are why your power is low. The converter recomended to me was for street/track duty was a 4000-4200 by 2 different converter companies, and a 3600-3800 for my setup on the bottle. On a side not, regardless of preload I don't believe the stock lifters will survive awful long with the spring pressure of the 26920 springs.

 

realistically, you should spend some money and get yourself a set of high quality lifters. Sure there are alot of people using stockers on the LE stuff, but Bret and LE advise against it for a reason ... Theres also enough people that have lifter/vavletrain problems and its just not worth skimping the extra couple hundred bucks.

 

Hey Kyle, I'm def looking into a 4000+ converter now and some better lifters. I guess I didnt realize just how high this cam had to wind to see its power. We're going to try and play it safe and shut it off around 6500.

They found out today the coil was bad so that was not allowing the car to start. That also explains the popping. Tomorrow they are going to throw in the stock injectors and see if it runs better.

 

Don't buy the converter if it doesn't multiply torque. From what I understand, the good ones do this at a 2:1 ratio (200ft-lbs at the flywheel=400ft-lbs at the transmission input shaft)....

http://www.converter.com/torqueratio.htm

You really think oxygen can travel several feet from a pinhole in the exhaust, back to the sensor? The car runs open loop and mafless. So there is little room for "false corrections". BTW, I totally agree with you on preload. I usually go 1/8th turn or slightly under. Never over 1/8th...

 

The tuning file was e-mailed to me and there is a problem in the lower kpa settings below 2800 rpm. It has 23 degees of advance @ 100 kpa and only 400 rpm. The stock setting at the same rpm/kps is 6 degrees. MTI has 3 degrees in the same range. Others in the below 2800 range are off too and that is the source of the surging.

In the 4000 – 7000 range with a couple of exceptions is a virtual match to the MTI program that has circulated the internet. Checked the Wot fuel/air tables comparing them to both stock and the MTI program and they have been custom tweaked so perhaps that accounts for the 420 rwhp (which I think is good).

Get the lash right, correct the timing tables with other tweaking and the car is probably good to go. I always replace the 02 sensors before a major tune and that almost always seems to help along with checking everything else to make sure the car is 100%.

 

What difference does it make what the WOT timing advance is at 400 rpm?? As long as the car starts (w/out having to hold the throttle all the way open), it should never see that part of the table and certainly is not going to affect the way the car pulls up top.

Surging is something that needs to be corrected while driving the car. Every car (especially with different cams) is going to be surge a little different and is going to need different amounts of timing in that region to get rid of it. I haven't seen the tune, but unless the timing is way off in the cruising area, you can't say how much retard/advance it would take to cure the surging.

Also, nothing was said about surging. The car is stumbling (back firing) around 3000 rpm. I didn't read anything about surging, unless I missed something.

The a/f tables you are looking at are not what was adjusted on this car for the a/f. This car has a speed density tune and all of the a/f tuning is done in the VE tables.

And what car had 420 rwhp? The MTI car?

 

I'm going to have to say: Whoops! Posted on the wrong topic. Sorry guys but I got two confused as to which was which.

In terms of generic tunes......yes if the advance is way out of wack at lower rpms' (was was at several points not just 400rpm and 100 kpa - I posted that because it was 20 degrees of at that point along with others) it will effect drivability. In the other case there was an idle/surge issue.

Also, the 420 rwhp was from another post that is somewhat similiar. My fault.

This time I'm not even drunk. Give me a few hours.

 

I was wondering what was going on.

 

LoL As I said before you are a stand up guy !!

 

Maybe stand-up......just a little confused at times.