JeremyF

iTrader: (23)

Here are the results of our LS4 intake manifold porting before and after testing. We did this on a 100,000 + mile 2005 Grand Prix GXP with typical bolt on's like CAI, Catback, and also a 3400? stall converter and just installed rockers and LS6 Spring. We were battling sweltering dyno conditions of 95 degrees, very high coolant and IAT temps, which - when coupled with the big stall converter -explain the lower numbers for this car. We also installed a ported throttle body, but that has no additional horse power gains.

Bottom line: the intake and tune netted an increase of 30 rwhp and 18 rwtq gains.



05 GXP on the Dyno:


The LS4 intake that was removed:


Another:


The ported one being installed:





Run # 4 shows the car with a rough tune (eliminated spark knock found on previous runs and very rich) prior to changing the intake out with our ported intake.

Run # 6 Is with the intake swapped (on the dyno -VERY hot) and the tune being cleaned up some.

Run # 8 is the final tune with the intake. Did a drivability tune after that and then a street tune to make sure everything is in order.


The end result:



Thank you BJ for making the very long road trip to get this done, as it was great meeting you and your dad.

If anyone is interested in having their LS4 intake and throttle body ported pricing is as follows (on an exchange basis):

Porting the intake and TB $400 ground shipped back-48states
Porting the intake only $300 ground shipped back-48 states
Porting the TB only $125 ground shipped back to the lower 48

Dyno tuning is $400.00 plus cost of the dyno (in this case it was $80.00)
Street tuning is $300.00
Mail order tuning is $275.00

www.fasterproms.net

fastproms@tampabay.rr.com


Thank you!

Dan
Fasterproms

ImpSS07

iTrader: (3)

So overall after everything was put on and tuned the highest HP you got was 250.2? Explain where the 30hp increase was? Our cars should be close to 250hp to the wheels with just a cai and exhaust.

neilownz

Interesting starting numbers. It jumped from 220 to 250 at the 5700rpm line. That's where 30hp is made. Wonder if 06+ would have better numbers becuase of the new map sensor etc.

slomaro2

iTrader: (4)

Hi All.

Thanks again Jeremy, you guys were great.

I have to vouch for Jeremy, Dan and Laz. These guys worked very hard and were extremely hospitable.

Anyhow, the initial numbers were way lower than I expected, and I'm hoping that's mostly attributable to the extreme heat and my higher stall converter. I tried not to focus on the starting point (I'm well aware that with my starting point with all the bolt-ons was lower than most people's stock numbers--I'll have to figure out what's going on there.)

I stood there and watched Jeremy and Dan swap out my stock intake and TB for the ported units and, with no other changes, the first pull netted a 30 whp increase. It pulls like a raped ape up top. These guys and the intake/TB combo is the real deal folks. By my estimation this is the best bang for the buck mod for our cars. If you could've seen in person how much material is removed from our stock manifold and how much work goes into these, you'd understand how.
Again, please take into account the percent gained, not my uber-low numbers (that was a kick in the twins that I'll have to figure out.) I honestly expected to start off around 260whp and then fully expected to pick up another 20-30 for the intake. I was beside myself when I saw the low starting point, but the dyno doesn't lie and I'm a big boy, so it is what it is. It did cheer me up when we picked up the extra thirty ponies with the intake.

Also, Jeremy's tune turned the car into a beast. Suffice it to say, sleep deprivation not withstanding (I worked a long day on Wednesday then picked up my Dad an hour from here, then we drove straight from Houston to Tampa--about 990 miles one way.)

Thanks again guys.

For anybody reading, I don't see how anyone could skip this mod, especially for the price.

Also, I'm wide open to any thoughts on what's up with my car.
Many thanks,
BJ

Panther427

What kinda Dyno do they have?

slomaro2

iTrader: (4)

it was a dynojet.

neilownz

You can see how much is removed by looking at the green gaskets in all of the pictures.

Corny40

iTrader: (7)

Why on earth would you drive all the way to Florida to have this done? There are tons of speed shops in Houston, many of them ls1tech sponsors too. I'm sure you could have found one to do this for you. :?

slomaro2

iTrader: (4)

Hi Corny.

I drove to FL because these guys have a good reputation for their tunes and port work (after some of the experiences I've had in the past, I won't go near a shop that doesn't come highly recommended.) The half-off offer didn't hurt either.

Also, it was a good opportunity to take a road trip with my dad, which kinda' something we've done a few times in the past. We had fun.

Thanks,
BJ

LS4SPEED

iTrader: (3)

That's an awesome increase to the wheels! I still wonder tho how much actual power just the porting increased without the tune. Or should I put it this way, how much hp could you have gotten out of the tune without the porting? I believe you prolly could gotten close to 30 hp with just the correct tune. Not knocking the port job, just curious.

It's always nice to spend the time with the old man, that would have been enough to justify the road trip. I bet the ride home didn't take as long as the ride there, did it?

slomaro2

iTrader: (4)

We did make a bit better time on the way home. It's been awhile since my dad and I took a road trip and this was a perfect opportunity.

As for the tune vs. the porting, the difference between run 004 and 005 was only the addition of the ported items, which netted the 30 hp. We had a total of nine pulls and the tune by itself was substantial.

I still have to figure out what is off on my combo, of course. Judging from the other combos and dyno sheets I've seen, I think I should be closer to 300 whp. I'm going to run the car with my dynolicious software, clean the MAF and run it again to see if that makes any improvement. I'm definitely stumped, though. I don't want to jack this thread so I'll post another with my mods and to get everyone's thoughts.

Thanks,
BJ

LS4SPEED

iTrader: (3)

[QUOTE=JeremyF;12179098]

Bottom line: the intake and tune netted an increase of 30 rwhp and 18 rwtq gains.

Wish I coulda got those RWHP & RWTQ gains for my FWD. I woulda kept it longer.

Corny40

iTrader: (7)

Well, I guess that's as good a reason as any. I'm glad y'all had fun!



So, what all is involved in removing the intake? Is it very difficult? Since my Impala is not my DD, I can afford to be w/o her for a while. The wheels are definitely spinning.

Does this porting weaken the TB or intake at all? Is there any chance of them cracking, due to this work?

Is there any sort of warranty/guarantee?

neilownz

You just need a fuel line release little plastic tool.

JeremyF

iTrader: (23)

In this case, the vehicle started with 220. As BJ stated, a dyno doesn't lie, it's a measuring tool. We were there to make a base line run and then swap, make a run and then tune. This is what is shown.

Run # 4 shows the car with a rough tune (eliminated spark knock found on previous runs and very rich) prior to changing the intake out with our ported intake. 220/234

Run # 6 Is with the intake swapped (on the dyno -VERY hot) and the tune being cleaned up some. 244/245

Run # 8 is the final tune with the intake. Did a drivability tune after that and then a street tune to make sure everything is in order. 250/252

A different MAP sensor will have no effect.

Maybe next time we will conduct an A - B - C test to see which is which. But for this case we wanted to see how much hp and tq could be gained with swapping a un ported manifold while the car was still on the dyno with our ported one, and then making another run. The answer according to a proven measuring device was a peak gain of 24/11.


The intake removal with the exception of the bolt in the passenger rear side corner under the alternator bracket is pretty straight forward.

We have done hundreds and hundreds of these LSx intakes an throttle bodies with no structural integrity issues following

Bj,

Thank you again and also for answering some of these questions in here.

I think what is getting lost in here from the lower than expected baseline run #s is how much of a restriction the manifold's for this engine is. If ported, the increased air flow coupled with the increased plenum volume, increases the horse power and torque being made. By removing these restriction in the throttle opening, ports and inside the plenum, you make measurable gains. This is how the FAST manifold works on other LSx vehicles, we simply wanted to see how much of a difference a ported LS4 would make.

Thanks
Dan
Fasterproms

Sittingmongoose

iTrader: (1)

i got my stuff ported out by a friend, but i feel like you guys can do a more aggressive port, might send my stuff in.

06 SS

Ok...so +24 horsepower after intake swap and a pretty close tune (as final tune only gained another 5). That is compared with a terrible tune in place first. So the intake was maybe worth 10-15 horses on it's own? That sounds pretty dang good for $300 odd! Soon as I pay off the engagement ring, I am going to be giving Jeremy a call!

JeremyF

iTrader: (23)

I have two ported LS4 intakes on the shelf right now. Easy mod to do and a great bang for the buck.

Sittingmongoose

iTrader: (1)

how much are core swaps?

JeremyF

iTrader: (23)

Core charges are $275.00 each for the intake and throttle body, refunded when we receive your undamaged cores back.