TracyRR

iTrader: (8)

How much seat pressure should i run with this XER cam - 238/244 .612/.610 lift? I can tell you i am having valve float right now over 5200 rpms with only 13 pounds of boost. I checked springs pressure today and it has approx 130 on the seat at 1.78 installed height. I plan on cranking this thing up well over 20 pounds when i hit the track. Just trying to figure out if these springs can be shimmed enough or am i going to have to buy another set of springs. The Trick Flow springs i'm using now are supposed to be 150 pounds at 1.80 and 438 pounds at 1.20 open. I'm using comp replacement lifters, trick flow valves and yella terra shaft rockers. Any advice would be appreciated. Thanks

Nitroused383

iTrader: (10)

Depends, what valves and rocker arms? I would run HUC lobes as XER lobes are not the most stable lobe and the stock trickflow valves are heavy. Maybe talk to TEA about turning a set of LS3 valves down for you, its a good upgrade for valve train stability. Probably need 170-200 lbs depending on the variables especially if you're not running stock rockers.

Does your map sensor get wavey when you think it's floating the valves? Car probably stutters too, right?

TracyRR

iTrader: (8)

hey nitroused, i updated my orig post with more info. It has yella terra shaft rockers and stock tfs valves. When it floats the valves (still assuming it is float at this point), it will not pull past 5500ish rpm's. It pulls real hard till about 5k and then kinda hits a wall after that. I have read that xer lobes require more seat pressure. If at all possible, i would rather not pull the top end down to correct this issue. These new tfs heads can hold a much larger spring. The spring pocket is close to 1.50. Thanks for the reply.

Nitroused383

iTrader: (10)

No problem, you might want to PM Brian Tooley as he will have some great info and steer you in the right direction. I know he frequents yellowbullet but I'm not sure if he's on here much.

stevieturbo

Brian is no longer at TEA/TFS as far as I know.

5500rpm seems very low for it to be a valvespring problem. Although it is possible. What sort of mixtures are you seeing before and when it happens ?

Shawn @ VA Speed

iTrader: (3)

for 20 lbs of boost and the parts you have i would look at a PAC or Manley spring. The std trickflow springs really aren't happy with those pressures. I would shoot for 180+ on the seat. Just be sure you have your valvetrain geometry dead on and you will need a pretty robust pushrod-with the trickflow heads you usually can't fit a 3/8 with doing some grinding so I would use a 5/16 .120 wall.

TracyRR

iTrader: (8)

hey stevie, the afr is in the mid to upper 10's before and after it occurs. I don't feel it missing, it just hits a wall and doesn't make any power over 5k and won't rev.

hey shawn, yes, my swipe on my valve tip is super tight and i was about to call manton for some pushrods. My pushrod length is 7.425 but i only have at quarter turn on the preload (comp replacements) so i guess i'll go a bit longer as well. Thanks guys!

Nitroused383

iTrader: (10)

You can get manton push rods in 11/32 that fit on trick flow heads. I wouldn't expect heavy tfs valves with roller rockers and 130lbs of seat pressure to pull past 6000 rpm on a n/a setup with xer lobes.

ablakez28

iTrader: (9)

This is EXACTLY what my car was doing on the dyno today. Sorry to intrude on your thread but I need to know where to look as well. Only thing is on mine it pulled really nice and smooth on the street then i put it on the dyno and this happened!!!! Ughhhhh almost exact same rpm too. Around 5k in 4th. Any help would be appreciated guys. Im dying here.

TracyRR

iTrader: (8)

Calling for manton pushrods today, thanks

Best of luck

ablakez28

iTrader: (9)

Just to update I had my map scale off. I had it for 3bar and I have a 2.5bar.

TracyRR

iTrader: (8)

Update for you... i installed some k-motion k800's. No more valve float!! I installed them at 1.84 installed height with around 170 on the seat and now that bitch buzzes. But....now it appears that i'm maxing out my 80 injectors.... 127 duty cycle at around 6k rpm with 13 pounds of boost. Base fuel pressure at 58 with a 1:1 aeromotive regulator. Specs in my sig. I will double check fuel pressure while blasting tomorrow but both deatchwerk 300+ pumps appear to be working properly. I was hoping that the 80's would get me in the four digit wheel hp area (without meth) but it doesn't appear that they will. I have meth but have it turned off on these low boost tuning blasts.

What size injectors should i go with to max these turbo's out (1200 - 1300 rwhp)?

I'm new to efilive tuning so i'm taking my time. I'll update tomorrow. Thanks for the great advice on seat pressure!!

Nitroused383

iTrader: (10)

I'm glad you fixed your valve float issues! I hate swapping valve springs on the car, hurts my back thinking about it. Did you get a new set of pushrods? How do you like the DW301 pumps, are they quiet? Are you leaning out on the top end, I wouldn't think 80lbers would be maxed out @ 13lbs of boost with a 1:1 regulator.

TracyRR

iTrader: (8)

I bought the new LSM valve spring compressor and it made it very easy!! I had another brand name tool but did not work because of the different valve angle of the tfs heads. I highly recommend the lsm tool.
Yes, new manton pushrods 11/32 and .120 thickness. Very nice pushrod!
I'm going to hook up my mechanical fuel pressure gauge so i can see what it is doing. I was blasting with a 1/2 tank so i will fill up to make sure i wasn't uncovering the pumps. I'm kinda hoping that is the problem because i just priced new big injectors....ouch, sticker shock! Looking at my log, at 5000 rpm's, my duty cycle is 95% and it goes to crap from there as rpm's increase. The dw301's are supposed to be bad *** and yes they are quiet....i can't even hear them but my car is kinda loud. Thanks man, i'll update the thread today with more info.

TracyRR

iTrader: (8)

ok, i think i'm alright for now... I was having issues with the signal on my aeromotive boost regulator. I changed the source and it is an improvement. Now i'm at 90% duty cycle at 15 pounds of boost. Still not great but better. Thanks for the help! tracy

TracyRR

iTrader: (8)

Update....i changed to manton 11/32 .120 wall pushrods and k800 k-motion valve springs. The seat pressure is approx 175 at the seat (1.835 installed) and 495 open. The motor pulls really really hard but still hits a wall at 5600 - 5700 in second gear. It will basically hover around 5800rpm's no matter how long i keep it down. To complicate matters, it will pull hard to 6600 rpms in first gear (although it has tire spin). I checked back pressure and it was a good 1.25 ratio at 15 pounds. A well respected racer recommended i try a stock rocker (versus the ultralite yella terra's i'm using) to rule out excess weight on the valve train which i will do... but while i'm waiting on some stockers to come in, i wanted to see if you guys had any other suggestions. I inlcuded an efilive log. You can go directly to frame 2555 in the log. Thanks

Nitroused383

iTrader: (10)

Does it happen if you turn the boost down?

TracyRR

iTrader: (8)

The lowest i've lowered it has been 13 pounds. I have an RJC valve on it but i will lower it to see what happens. thanks

Chris@CBR

If the all else fails don't over look the plug gap.
I've seen motors lay down like this due to spark blow out.
It gets worse and happens sooner as you turn the boost up.
Don't be scared to gap the plugs in the mid 20's.

This may not be the issue but it's easy to gap the plugs and rule it out.

TracyRR

iTrader: (8)

Yes, they have been gapped to .022. I change plugs every couple of months just to keep an eye on things and the plugs have looked pretty nice. Thanks chris