tjwong

This evening I worked late finalizing a tune on a head, cam, header and a Cory special ported LS2 intake combination. Here are the results:



The cam is a LPE GT-11 with the following specs: 215/230 duration .631/.644 lift ground on a 118 LSA. This cam has a near stock idle quality so drivability is basically like stock. As you can see I gained nearly 100hp with this combination. The heads are 243 LS6 castings with 2.05 intake valves and PRC gold springs. The porting is on the mild side but flow numbers indicate that they would equal other aftermarket heads easily at a considerably lower cost when compared to name brands such as ETP, RHS or AFR. The headers I used are American Racing headers that flow into a stock rear muffler section, CATs are used and supplied by ARH. I don't now how much Cory's ported LS2 intake added to the gains.

Also this car is a A6 car and the test was conducted in 3rd gear, the numbers are basically unchanged when tested in 4th gear. I was impressed with the numbers, and overall OE drivability. Just a few months earlier I dyno'd a 06 C6 Z06 that made 446 to the wheels as a baseline! This car now almost makes Z06 power output which I am are very pleased with. I beleive if this car had a Corsa or other aftermarket rear muffler section there could have been another 10hp to be had!

CHarris

iTrader: (5)

Great results, Tom. Especially from an A6. A6's always seem to post up low on the corvette forum. It's great to have been able to contribute to this car.

Tell us more about the heads...


I hope Ray brings it back by when he drops off the core so I can get a ride

BTW... we've seen an additional 5-10 rwhp from my ported LS2/LS7 TB's as well.

CharlieCobra03

On a Mustang Dyno no less.

Mikey 97Z M6

iTrader: (37)

Great numbers!

I wonder how long those springs will last in a daily driver, with .640" valve lift..... Jeeezus, that's nearing MS4 territory for lift.........

Mike

Ryan'sSS

iTrader: (15)

Excellent #'s.
With those lift #'s I would think the cam is on a LSK lobe.

Spinmonster

You picked up power even as low as 1500rpm! Good job.

tjwong

That is exactly what the customer insisted on. I put my **** on the ledge on this one by promising him gains under the curve! I did some research on this one via old magazine articles and speaking in depth with the LPE people who are known for making big numbers and having to pass emissions and without big cams. I use a similar cam in pick up trucks and SUVs that make similar gains but of course not as high peak numbers in the 5.3L trucks. However I am about to embark on a 07 6.0L H2 Hummer with the same package to see how that is going to work. I am hoping to make a Cadillac Escalade killer out of that Hummer!

99blancoSS

iTrader: (115)

My guess is the lobes are mild. Similar to mine. Or maybe less aggressive is the best term.

Mikey 97Z M6

iTrader: (37)

Actually it's just the opposite. The longer the duration per given lift, the easier the ramps will be on valvetrain components. Less duration and more lift (like this cam), means the ramps are SUPER steep, and very hard on valvetrain components. I'd give those springs about 6-8k miles before they start showing signs of giving up.

When I first saw the specs on that cam, I thought it was a solid roller.......... Impressive, but not what I'd call "small", and certainly not practical daily driver.

Mike

CHarris

iTrader: (5)

I don't think its nearly as hard on springs as you believe. LPE isn't big on failed engines from their shop. They tend to make everything that's a "off the shelf" part very safe and reliable. I'm sure this cam falls into that safe category.

tjwong

Exactly, in fact this is the very same cam that LPE uses in their 500BHP LS2 package that they warranty for 2 years!

jimbob

iTrader: (4)

Great job Tom and Cory.....Now Cory, if you would just advertise to those Corvette guys.....

jimbob

iTrader: (4)

TJ...
You and Cory sure made some good power....Cory needs to step up into the Vette arena. To bad they cost so much for advertising....

Mikey 97Z M6

iTrader: (37)

First of all, Tom/Cory, great job with this setup. It obviously works, and if the customer is happy in the end, you did well. There's only a small handfull of shops/people that I would publicly recomend to anyone, and you're on that list.

LOL,,, let's not change the topic here; I didn't say anything about reliability, and it probably is "safe" as far as reliability goes. Typically an engine won't "fail" because of worn out spring pressures unless piston to valve contact. I ran my comp 987's into the dirt, 310 nose pressure new, 230 nose pressure when I tossed em in the garbage. I didn't suffer a failure with mine, but power was down considerably because of valve float above 5700. But, they also had over 35k miles on them by the time I replaced them.

I'm not saying that cam won't perform well, or saying anything bad about Lingenfelter, or trying to discredit Toms hard work. All I'm saying is, if you're going to play with a hydraulic roller cam that has .640" lift, and expect the springs to live 16-20k miles, then you must live in a world where the laws of physics don't apply.

People are typically getting 16-18k (+/-) out their springs on cams with FAR less lift, and more duration (which actually helps the springs because of ramp speed) than .630 -.640". Now take into account that 215 degrees of duration is a very short amount of time to flick a valve open to .630", then snap it back down shut. Those must be some wicked ramps.

Here's the deal, I personally don't believe those springs will last over 8k miles with that cam, and still produce the same power it did on that dyno. I'm going to make a highly "grasping in the air" prediction and say that it'll be 25-35rwhp down by 8k miles on the same springs. Just a prediction, and just my opinion.

Just in case anyone has forgotten just how much lift .640" is, here are some popular cams w/specs.


Comps 224 .581/.581 112
TSP 231/237 .598/.595 112+2
G5X2 232/240 .595/.609 112 or 114+4
TR Trex 242/248 .608/.612 110+2
FMS FM 13 230/232 .591/.585 112 or 114
LPE GT2-3 207/220 .578/.581 118.5
TSP 225/225 .589/.589 112
TSP 233/ 233 .595/.595 112
MS3 237/242 .603/.609 113+0
TSP 233/239 .598/.603 113
FM14 232/234 .600/.600 110, 112, or 114 lsa

It's late, I'm tired, and I still have more homework to finish.
Mike

LSxChevelle

iTrader: (4)

Nice job guys!!

99blancoSS

iTrader: (115)

SO Mike your thinking I should be looking at and pro'lly changing my springs around 8000 miles as well? I've got a cam motion 234/240 with .637 and .641 lift. running the PRC doubles rated at .660 Thats if I ever get it back.

Mikey 97Z M6

iTrader: (37)

Would I suspect that you'll be down on HP? Yes. But even your cam is not as radical, "lift wise" as that Ling. cam, because you have enough duration for a decent duration/lift ratio on the ramps.

Mike

CHarris

iTrader: (5)

I had very little to do with this combo. The credit belongs solely to Tom. I was just able to put a little icing on the damn good cake that Tom cooked up. Ya'll didn't know that he could bake did ya?

Good work, Tom. I'm happy one of my intakes could sit on top of your well mannered monster and feed it better!

Layn_Low_247

iTrader: (1)

Great work as usual Tom!

CHarris

iTrader: (5)

Got to go for a ride in this car today... Lets just say it was quick trip.

It's also really deceiving as it sounds like a headers only car. Seriously... it idles at about 650rpm. You'd never see this train coming.

Congrats on the car, Ray!