Burken01

iTrader: (88)

hey all, I want to see what some of you XER cam lobe guys are running as far as valvetrains... which rockers, pushrods types (which brand, OD, etc...) lifters, valve springs and what spring pressures they are at?

I purchased the "TU1" speed inc cam (225/225 .581/.581 113+1) and never payed attention to what lobes it was ground on... I recently found out about how aggressive XER lobes are and in boosted app's that it isn't recommended by alot of builders.... But some have run them with sucess so I would like to hear about your valvetrain your using to keep them under control..

my setup is:

- 317 heads + Stainless Steel 1 piece valves (Intake 101 grams, exhaust 90.5 grams)

- BTR .660 platinum springs w/Ti retainers installed per specs -Spring specs are 155 lbs @ 1.780", 380 lbs @ 1.180", 400 lbs @ 1.130, coil bind @ 1.070"

- Stock Ls rockers with the CHE bushing upgrade

- Lingenfelter Performance HD steel rocker stands

- ARP rocker arm bolt's

I have not purchased lifters yet, but I'm almost dead set on morel 5206 link bars unless if some more experienced people say otherwise...

How stable does this setup sound on a 76mm turbo Iron 347 and hoping to boost between 14-18 psi?

this is my first turbo build and the shortblock is being built as we speak but I can still make a cam change, lifter change, etc.. at this point in the game..

Id like to keep the TU1 cam since I just got a converter spec'd to my setup but I'm open to ideas, insults, criticism,

I do not have pushrods yet as I'm waiting to measure last, but I was looking at bigger OD manton pushrods but kinda don't want the extra weight on the valvetrain but then again I'm still learning about that lol

Wicked69

I was running the XER273 224/230 .581/.588 114. Stock everything on a 179,000 mile 6.0 with 5.3 stock untouched heads and patriot gold springs to spec. I ran some low 6.0's in nearly 4,000lb Chevelle. No issues with the stock valve train. Just to see if I am leaving anything on the table I am getting ready to try one of Martin's custom cams and aftermarket pushrods

Burken01

iTrader: (88)

sweet, nice to hear that it worked fine... yeah I'm interested in seeing the change when you switch to the tick cam...

quik67

I used a MS3 cam 237/242 .603/.609
I used Lunati .660 duel springs.
regularly spun it to 6700 rpm with 15 psi boost.
I used this cam for 3 years, no problems at all.

Burken01

iTrader: (88)

^^ nice nice, stock rockers I'm assuming?

hellbents10

iTrader: (10)

I think you will be just fine, I have not had any issues under 22psi with them.

qqwqeqwrqwqtq

You will run out of usable RPM range of your turbo long before stability becomes a problem. I would shim the springs for 175-180lbs on the seat.

That's probably the most common problem with valvetrain that I see. People look at the spec's of a valvespring but don't actually measure installed height or shim it to achieve the proper pressure.

EDIT- corrected information

quik67

yep, stock rockers

Ryans99ls1

iTrader: (16)

mine does fine with XER. stock rockers, Comp 921 valvesprings and TSP pushrods. vavlesprings were on a few thousand miles before boost and have since seen a couple thousand more

Burken01

iTrader: (88)

heres the cam card



I keep hearing XER since the grind # is 3722R/ 3722R, I tried looking up the grind # on comps website but that website is hard to navigate since Im a cam noob...

Ok so I need to shim my springs to 180? thanks I just talked to my builder and will get that done soon, I shoulda known better to just get the springs installed per what the spec sheet on them say , just a small road bump..

I'm still learning everyday..

Burken01

iTrader: (88)

yeah I guess i just need more than 155# spring pressure to make them more stable....

qqwqeqwrqwqtq

You are right, I stand corrected. TU1 is XER TU2 is Xtreme RPM.

Regardless, most of the stuff we use the TU1 on doesn't spin much past 7k rpm and we've experienced no valvetrain failures or any hint of instability with it.

Burken01

iTrader: (88)

sweet thanks!! Yes I plan to shift around 6600-6800... how does that sound?

qqwqeqwrqwqtq

Sounds like it will work out great, just set the springs up correctly, run some good pushrods and personally I aim for around .070-.080 lifter preload.

Burken01

iTrader: (88)

what brand and thickness pushrod would you recommend?

And I kind of want to get rid of ls7 lifters because of the plastic lifter trays, what do you think of the morel 5206 link bars? or do you have another recommendation..

thanks for the help

Wicked69

I set my springs to specs on the sheet. No problems and spun the motor to 7k pretty easily. Why the higher seat pressure? Is it only necessary with XER lobes?

Burken01

iTrader: (88)

I talked to Brian tooley this morning about his springs, he said that the 155# seat pressure should be fine, but since speed inc uses that cam all the time Ill prob shim them to 180...

Any down side to running higher spring seat pressure? 180 vs 155