Wtf
Thread Starter
Racer
Joined: Aug 2007
Posts: 305
Likes: 1
From: DRAYTON VALLEY ALBERTA
Wtf
OK so I got my Trick Flow 175cc heads 56cc combustion chamber, my comp cam(08-466-8), nothing to radical,1.6 RR, Heddman Elite hedders, and the First Injections Intake, 30lb FRP injectors. I had a prom burned. Fired up with open hedders and it fires/runs like it has a major huge cam in it, kinda spits and sputters then ramps up to like 2500rpm or so,then i shut it off. Whats the deal, anyone.
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
OK so I got my Trick Flow 175cc heads 56cc combustion chamber, my comp cam(08-466-8), nothing to radical,1.6 RR, Heddman Elite hedders, and the First Injections Intake, 30lb FRP injectors. I had a prom burned. Fired up with open hedders and it fires/runs like it has a major huge cam in it, kinda spits and sputters then ramps up to like 2500rpm or so,then i shut it off. Whats the deal, anyone.
So you took a cam with .570/.565 lift, then you added 1.66 rockers to make .608/.602 lift? On trickflow 175s? Oh boy.
-- Joe
Melting Slicks
Joined: Aug 2003
Posts: 3,389
Likes: 391
From: Lakeville MI
From the cam spec sheet, it looks like 0.570/0.565 lift is with 1.6 rockers.
Lobe lift: 0.357/0.354
Reliable sources suggest that those heads stall/swirl around 0.500 lift.
With 1.5 rockers:
0.535/0.531
You may want to consider 1.5s on the intake, but I don't think that's your idle problem. With only 46 degrees of overlap at 0.006, that cam should be pretty mild.
Back way off on the throttle opening if its idling at 2500 rpm. What can you tell us about the chip tune?
Lobe lift: 0.357/0.354
Reliable sources suggest that those heads stall/swirl around 0.500 lift.
With 1.5 rockers:
0.535/0.531
You may want to consider 1.5s on the intake, but I don't think that's your idle problem. With only 46 degrees of overlap at 0.006, that cam should be pretty mild.
Back way off on the throttle opening if its idling at 2500 rpm. What can you tell us about the chip tune?
Last edited by tequilaboy; Sep 24, 2008 at 01:31 PM.
Thread Starter
Racer
Joined: Aug 2007
Posts: 305
Likes: 1
From: DRAYTON VALLEY ALBERTA
I had the PROM burnt from a guy in Tilley Alberta. "Westers Garage" is the name. I gave him all the specs like I did in my first post and he burnt it for me. What do you suggest. I gave him way more detailed specs actually.
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Melting Slicks
Joined: Aug 2003
Posts: 3,389
Likes: 391
From: Lakeville MI
I would suggest that you get an electronic copy of the bin file that your tuner burned for you so that you can read it with one of the commonly available editor programs.
Another option would be to have your tuner simply export the tune to a text file, and send you a copy so you can at least see what you have in the tune.
Tune related items that will be interesting regarding an idle issue:
MAF table #1
MAF scalar #1
Spark advance table
Desired idle rpm table
injector constants
injector low pulse width offsets
injector battery voltage offsets
open loop fuel vs load
open loop fuel vs coolant temp
warm iac park position table
O2 related tables
Car related items:
valve adjustment
installed cam timing (advanced or retarded cam timing)
vacuum leaks?
exhaust leaks
O2 Sensor exposed to air with open exhaust
altitude?
Transmission type (auto or manual)
Fuel pressure (without vaccum)
min air adjustment rpm
base timing with est disconnected
tps voltage with closed throttle
IAC counts in a normal idle
manifold vacuum in a normal idle
correct firing order
Another option would be to have your tuner simply export the tune to a text file, and send you a copy so you can at least see what you have in the tune.
Tune related items that will be interesting regarding an idle issue:
MAF table #1
MAF scalar #1
Spark advance table
Desired idle rpm table
injector constants
injector low pulse width offsets
injector battery voltage offsets
open loop fuel vs load
open loop fuel vs coolant temp
warm iac park position table
O2 related tables
Car related items:
valve adjustment
installed cam timing (advanced or retarded cam timing)
vacuum leaks?
exhaust leaks
O2 Sensor exposed to air with open exhaust
altitude?
Transmission type (auto or manual)
Fuel pressure (without vaccum)
min air adjustment rpm
base timing with est disconnected
tps voltage with closed throttle
IAC counts in a normal idle
manifold vacuum in a normal idle
correct firing order
Last edited by tequilaboy; Sep 25, 2008 at 03:47 PM.
Instructor
Joined: Feb 2008
Posts: 201
Likes: 0
From: The Ham AL
I can attest that a vac leak will do what your saying. I had a major leak and the car would not even idle. Ramped up to 2500 rps and then died every time. I ran a Marlboro Light leak test and verified it. I just buttoned her up last night with new gaskets and all is well.
Pro
Joined: May 2002
Posts: 635
Likes: 6
From: New Jersey
Put exhaust on the car, and see how it runs ,then go through the motions. When a computer car is too lean in closed loop it will try to compensate to get the correct A/F ratio that it was program for. I put 3" exhaust on my car and it leaned the engine out, so open heads will be worst. Check you A/F ratio first.