fm-14 in and car dies ..tuned
11-05-2008, 11:52 PM
#1
10 Second Club
Thread Starter
iTrader: (14)
Join Date: Mar 2006
Location: pittsburgh raceway park
Posts: 246
Likes: 0
Received 0 Likes
on
0 Posts
fm-14 in and car dies ..tuned ok i installed a fm-14 on my 98. it was tuned by bill from custom ls1 tuning and he did a great job with tuning it by mail order but heres the problems im having.
this is before tune.
when cam was installed i changed springs and put a double roller in and lined it up dot to dot, started it up idled nice then when i put it gear let out on brake it dies. fire it up idles ok for a coulpe seconds and dies. we adjusted the idle to 1100 to keep it runing so we could take for a ride. car gets up to 2500 rpms and up its flat and falls on its face when driving.
after tune.
so we parked it sent the pcm to bill, he did one hell of a job on the tune it idles at 850-900rpms. i let it idle for 5mins then jumped in pulled it in drive and set there for another 5mins with my foot on the brake and it idle fine. well i took it to the track and got there and drove it around the pit to warm it up alil make sure everythings ok. get in the line to get my numbers and get checked in left it idle while they put my number on car. jumped in got half way back to the trailer and it goes flat like it wants to die so i give it alil more gas, 2700rpms and its acting like its going to die so i pull in to my parking spot and hit the brake it cuts off. im lost im cussing at the car right now at this time because everytime i touch the damn car something goes wrong, its like the car is messing with me like it wants to **** me off. but anyway, when i start it back up to make a pass it sounds good idles nice so i get to make a pass, i go to do a burn out to get the slicks hot and it gets up in the 2700-3000 rpm range and its flat and just acts like it doesnt have the ***** anymore then 2seconds later its out of the **** and acting like it should. i launched it and it fell on its face and slowly picks up the rpms till 4000 and then it wants to pull but it doesn't pull hard like it used to. the car ran a 14:07x @ 91mph i believe on the mph.
the car feels and sounds like its loading up, because when i clean it out(rev it up), it is fine till i take it back up in the rpms. when i made the pass with it and it will leave hard but once it gets in like the 3-4.5k rpms it falls on its face like there isn't any more horsepower or torque there to keep it going. i know now my stock 98 oil pump is ready to go because its 40psi cold start and 10-15psi warm. i have no valve train nosie what so ever, and i changed the oil twice now and cut open the filter which had no metal shavings in it at all. i bought new cam bearings new oil pump melling 296 and ls2 chain arp rod bolts.
im lost on this i have no idea what i should do next with the car or what i should look for, the springs i used where comp 918's. once the car warms up it sounds and acts more like **** when it goes above 2000rpms. i love the fm-14 cam so im not even trying to say anything bad about FM, im just lost on this one but i do have all winter to mess with it. i thought i would post this up to see if anyone can give me some help as to what the problem is or could be, we're going to be pulling the motor here soon to go over everything, and start on the suspesion but thats just to have something to do over the winter.
this is before tune.
when cam was installed i changed springs and put a double roller in and lined it up dot to dot, started it up idled nice then when i put it gear let out on brake it dies. fire it up idles ok for a coulpe seconds and dies. we adjusted the idle to 1100 to keep it runing so we could take for a ride. car gets up to 2500 rpms and up its flat and falls on its face when driving.
after tune.
so we parked it sent the pcm to bill, he did one hell of a job on the tune it idles at 850-900rpms. i let it idle for 5mins then jumped in pulled it in drive and set there for another 5mins with my foot on the brake and it idle fine. well i took it to the track and got there and drove it around the pit to warm it up alil make sure everythings ok. get in the line to get my numbers and get checked in left it idle while they put my number on car. jumped in got half way back to the trailer and it goes flat like it wants to die so i give it alil more gas, 2700rpms and its acting like its going to die so i pull in to my parking spot and hit the brake it cuts off. im lost im cussing at the car right now at this time because everytime i touch the damn car something goes wrong, its like the car is messing with me like it wants to **** me off. but anyway, when i start it back up to make a pass it sounds good idles nice so i get to make a pass, i go to do a burn out to get the slicks hot and it gets up in the 2700-3000 rpm range and its flat and just acts like it doesnt have the ***** anymore then 2seconds later its out of the **** and acting like it should. i launched it and it fell on its face and slowly picks up the rpms till 4000 and then it wants to pull but it doesn't pull hard like it used to. the car ran a 14:07x @ 91mph i believe on the mph.
the car feels and sounds like its loading up, because when i clean it out(rev it up), it is fine till i take it back up in the rpms. when i made the pass with it and it will leave hard but once it gets in like the 3-4.5k rpms it falls on its face like there isn't any more horsepower or torque there to keep it going. i know now my stock 98 oil pump is ready to go because its 40psi cold start and 10-15psi warm. i have no valve train nosie what so ever, and i changed the oil twice now and cut open the filter which had no metal shavings in it at all. i bought new cam bearings new oil pump melling 296 and ls2 chain arp rod bolts.
im lost on this i have no idea what i should do next with the car or what i should look for, the springs i used where comp 918's. once the car warms up it sounds and acts more like **** when it goes above 2000rpms. i love the fm-14 cam so im not even trying to say anything bad about FM, im just lost on this one but i do have all winter to mess with it. i thought i would post this up to see if anyone can give me some help as to what the problem is or could be, we're going to be pulling the motor here soon to go over everything, and start on the suspesion but thats just to have something to do over the winter.
11-06-2008, 05:19 AM
#2
Assuming the tune is good I would just check all connections in the engine bay and check the plugs (pull a few), and make sure all coil packs and injectors are connected. Another thing is, make sure all the vacuum lines are hooked- ones in back of intake, side of intake, etc.
11-06-2008, 08:49 AM
#3
On The Tree
it sounds like you are fighting a vacuum leak to me if not a small, pesky electrical problem.
check your grounds and vac lines. if you dont find anything obvious put a vacuum gauge on the car at idle. surely someone here on tech has an F14 that wouldnt mind taking a vacuum reading off their car so you could compare the two.
check your grounds and vac lines. if you dont find anything obvious put a vacuum gauge on the car at idle. surely someone here on tech has an F14 that wouldnt mind taking a vacuum reading off their car so you could compare the two.
11-06-2008, 09:21 AM
#4
11 Second Club
Join Date: Jun 2005
Location: Was New Orleans, but swam to Baton Rouge
Posts: 1,537
Likes: 0
Received 0 Likes
on
0 Posts
Is it loading up or actually going lean? Are you still running the stock fuel pump? And if so have you checked the pressure on it when you increased the rpms?
11-06-2008, 09:34 AM
#5
10 Second Club
Thread Starter
iTrader: (14)
Join Date: Mar 2006
Location: pittsburgh raceway park
Posts: 246
Likes: 0
Received 0 Likes
on
0 Posts
i have the stock fuel pump on it for now, how would i check the vacuum on idle? to me it feels and sounds like its loading up but more then likey its going lean.
i just remembered that the pcv boot on the driver side valve cover is cracked on one side of it on the base the goes in the valve cover, could this be my problem? if so i order the whole kit yesterday.
i just remembered that the pcv boot on the driver side valve cover is cracked on one side of it on the base the goes in the valve cover, could this be my problem? if so i order the whole kit yesterday.
11-06-2008, 09:52 AM
#6
You have a serious issue and it has nothing to do with the cam specs. I went 11.62 @ 119 cam only with the f-14 so it makes power. My guess would be electrical, check all your plugs maybe your just running on 7. It's an easy fix so worth checking, I'm not sure if it would cause the car to run like that though. Hopefully it's not something serious, good luck.
11-06-2008, 04:54 PM
#7
10 Second Club
Thread Starter
iTrader: (14)
Join Date: Mar 2006
Location: pittsburgh raceway park
Posts: 246
Likes: 0
Received 0 Likes
on
0 Posts
checked all plugs and wires and everything is /was pluged in. im goning to pull all the plugs and check them maybe tomorrow or saturday to see how they look. im just lost on this because i dont know what else to do other then pull the motor and check everything and go from there.
Trending Topics
11-06-2008, 05:34 PM
#8
10 Second Club
Thread Starter
iTrader: (14)
Join Date: Mar 2006
Location: pittsburgh raceway park
Posts: 246
Likes: 0
Received 0 Likes
on
0 Posts
what fuel pump and injectors should i be runing with the fm-14 cam? im going to swap in a fast intake and new fuel rails just wondering what you guys think.
11-06-2008, 09:03 PM
#9
You shouldn't have to upgrade fuel if it's just a cam only set-up, I was on stock pump and stock injectors. I didn't touch the fuel until I added boost.
11-06-2008, 09:23 PM
#10
11 Second Club
Join Date: Jun 2005
Location: Was New Orleans, but swam to Baton Rouge
Posts: 1,537
Likes: 0
Received 0 Likes
on
0 Posts
Your stock pump could have crapped out. You need to get a gauge and put it on the schrader valve location on the fuel rail. Go put it on a dyno, or have enough line to place the gauge so you can see it, and see what happens when you get on the car. I am thinking the stock pump is bad, and would approach that angle. I have seen it happen before.
11-06-2008, 11:48 PM
#12
TECH Enthusiast
Join Date: Jan 2002
Location: Helendale, Ca (SilverLakes)
Posts: 531
Likes: 0
Received 0 Likes
on
0 Posts
I think that GM claims the stock fuel pump will go for 90K miles. There must be a way to hook up gauges to check flow and pressure. The PCM may even monitor the flow and pressure. Check for trouble codes.
11-07-2008, 07:44 AM
#13
11 Second Club
Join Date: Jun 2005
Location: Was New Orleans, but swam to Baton Rouge
Posts: 1,537
Likes: 0
Received 0 Likes
on
0 Posts