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-   -   Gen 1 4.7 (99-07) Manifold Porting Feeler/Discussion (http://www.jeepgarage.org/f6/gen-1-4-7-99-07-manifold-porting-feeler-discussion-34664.html)

FlyinRyan 01-24-2012 11:25 PM

Gen 1 4.7 (99-07) Manifold Porting Feeler/Discussion
 
Mods- If this is more appropriate to be in the vendor subforum, feel free to move as needed. This applies to WJ/WKs and this seems to be a high-traffic section of the site.

Lately I have had a few requests for 4.7 intake manifold porting. I've always kind of passed on it because other people claimed there was no power in it or that it was more worth it to swap to the '02 HO manifold (since discontinued). Theres never been any proof in the former.

As some of you know, I experimented with an '07 3.7 manifold- both the engine and the manifold are based off the designs of the 4.7, with some minor changes of course. The results of mild porting were very positive. No or negligible low end loss with drastically improved mid-range and top end. All without tuning.

In the case of the 4.7, theres a variety of manifolds that can be used. The best as-cast (or as molded) is the 08+ manifold. This is a proven design- I ran one myself, so I know how it works. However, the manifold requires adapters, and in my case anyways, had issues with low-end power.I found this out the hard way. The WK's EGR also does not work with the 08 manifold. This can be solved with an 08+ EGR (at least on the Rams), but again....more money.

I ran an 08 manifold with stock cams, and while it was great above 3k, it was no different if not slightly slower from idle to 3k. This made it somewhat less enjoyable to drive around town, even though I had a SCT custom tune. This was likely compounded by my lift and 31's. It is impossible to say, knowing what I know now, as to how dialed in my tune was.

I'd like to see how much interest there would be in porting a manifold for a Gen 1 4.7. The potential benefits would be:

1)Cost effective upgrade over stock
2)Provide a compromise between low end grunt and top end power
3)No fitment problems on WJs or WKs- Factory part with factory fitment
4)Potentially, a better match for those looking for a upgraded manifold with lifts, big tires, setups that require torque down low.

If there is enough interest, I may start buying manifolds for this purpose. Keep them in inventory like I do with TBs.

FlyinRyan 01-24-2012 11:44 PM

Re: Gen 1 4.7 (99-07) Manifold Porting Feeler/Discussion
 
Some food for thought.







http://wjjeeps.com/2002_2004_ho_manifold.jpg


Note the plenum inlet. It was likely that the 04 HO manifold (same as SO 4.7) was designed to elminate the dead space behind the TB inside of the manifold). This is evident in the 05-07 manifolds, as well as the 08+ manifold. The 02 HO manifold had shorter runners than any 99-2007 manifold. This minor improvement was likely made to keep power output the same.

I swapped a TB this past weekend on a '07 4.7 WK and while obviously I didn't get to see the runners in them, I got a good view of the plenum inlet. The nature of the plenum inlet is that it tapers in cross-sectional area before the 180* turn into the plenum, so what I could do is either epoxy the floor to eliminate the dead area on the floor of the inlet (it has a "step" down a few inches in, not visible in the above pic of the '04 HO) or enlarge where the TB sits and blend it into the step so it's all one flat surface.

Heres something else. Here's what a nitrous backfire does to a 4.7 manifold, LOL.

http://www.teamaudionutz.com/pics/kenny/trauma8.jpg

This appears to be an '03 or earlier manifold. In other pics of the album the TB style was the JTEC style (99-2002 in a dakota, which is what this is out of) . Note the seams. These seams are the same feature I was able to grind nearly flush in the 3.7 manifold, and get some improvements out of.

Here's a more extreme form of modification...I saw the pics years ago, but sadly the links are long gone. A guy cut open a spare manifold, and cut his runners down from 16" long to 3". Results: HUGE top end gains, without too much loss of low end. This was largely before custom tuning was available, so no telling if a custom tune would have helped (it likely would have). http://www.dodgedakotas.com/boards/per/13290.html

NHWK05 01-25-2012 09:48 AM

Re: Gen 1 4.7 (99-07) Manifold Porting Feeler/Discussion
 
When money is more available for me, I would deffinitly be willing to do this as well as another one of your ported TBs to go with it. For me i prolly wont be in the market to afford it for a year or so but id be down for it when money gets better if you end up doing it. What are we thinking about for pricing? im assuming you would do it like the TB, you port and ship and we ship back the core plus labor obviously?

FlyinRyan 01-25-2012 07:09 PM

Re: Gen 1 4.7 (99-07) Manifold Porting Feeler/Discussion
 
Quote:

Originally Posted by NHWK05 (Post 560271)
When money is more available for me, I would deffinitly be willing to do this as well as another one of your ported TBs to go with it. For me i prolly wont be in the market to afford it for a year or so but id be down for it when money gets better if you end up doing it. What are we thinking about for pricing? im assuming you would do it like the TB, you port and ship and we ship back the core plus labor obviously?

Its not really a matter of if I'll be doing it, I know I will, but if there is enough interest, I can start cranking them out on a regular basis.

I would probably source new manifolds, as used manifolds can be dirty, warped, cracked (very rare)....an 05-07 WK manifold is 120 shipped. A used manifold is not much, if any, cheaper.

As far as pricing, it would be depending on time spent porting (I price things roughly based on how much time it takes me to work on it). It would be competitive with the 08 manifold, so 300-450 is a safe range including manifold.

jeeppro 01-25-2012 08:55 PM

Re: Gen 1 4.7 (99-07) Manifold Porting Feeler/Discussion
 
whats the gain on this

FlyinRyan 01-26-2012 12:58 AM

Quote:

Originally Posted by jeeppro (Post 560762)
whats the gain on this

To early to tell exactly yet, but the 08 manfiold was good for about 20-25whp on a stock cam 4.7 . The 3.7 saw about a 10 maybe 15 whp gain...and id like to think I'd get the same out of this. Im usually pretty realistic in setting goals and expectations.

10-15whp= 15-20 at the flywheel

NHWK05 01-26-2012 08:39 AM

Re: Gen 1 4.7 (99-07) Manifold Porting Feeler/Discussion
 
So your looking to buy new manifolds, port them and sell them for less then an 08 manifold relatively equal power and direct bolt on right? Sounds like a plan to me!

cheapjeep 01-26-2012 01:48 PM

Re: Gen 1 4.7 (99-07) Manifold Porting Feeler/Discussion
 
So Ryan what your saying is the prime candidates are an '04 HO or '05 to '07 ? Also the TB's for up to '07 are the 3 bolt throttle cable type? I just want to make sure because I'm gonna start looking for an extra setup and eventually send it so you can just do everything at once. Also do you think my Superchips would be enough to run this combo at least for a while? I really don't feel like buying another tuner just yet.

Scottina06 01-26-2012 02:02 PM

Re: Gen 1 4.7 (99-07) Manifold Porting Feeler/Discussion
 
I have an extra manifold I may send you.....

FlyinRyan 01-26-2012 04:59 PM

Re: Gen 1 4.7 (99-07) Manifold Porting Feeler/Discussion
 
Quote:

Originally Posted by NHWK05 (Post 560962)
So your looking to buy new manifolds, port them and sell them for less then an 08 manifold relatively equal power and direct bolt on right? Sounds like a plan to me!

I do not think I will be able to match the gains of the 08 manifold , at least in terms of peak HP numbers. The shorter runners will produce higher peak numbers every time at the expense of low end torque. However, in an environment like the street or the track where area under the curve matters, this manifold *may* end up performing comparably if not better because the 08 manifold, at least on my old '02 WJ had a flatspot from 2k-3k. It screamed from 3k onward but I lost alot of momentum out of the hole.

Yeah, the idea is to get something that fits right without modification and is cheaper and more accessible to folks.

On a WJ, you're realistically spending at least 600 bucks installing the manifold. This is assuming you buy a new manifold, buy the misc hardware needed for the install, install the manifold yourself, and don't need any tools. And you'll have to cut the cowling.

On a WK, it is 600 + another 100 bucks or so for 08+ EGR. You could remove the EGR, but then you need SCT for tuning.......Then you need a datalogger....and a wideband...

You can say that it gets expensive fast...and suddenly the big gains don't seem so big.

I suppose I can port manifolds that people send me, but I'm not cleaning them or any of that, beyond the usual blowing of compressed air to get rid of dust, shavings etc.

Quote:

Originally Posted by cheapjeep (Post 561123)
So Ryan what your saying is the prime candidates are an '04 HO or '05 to '07 ? Also the TB's for up to '07 are the 3 bolt throttle cable type? I just want to make sure because I'm gonna start looking for an extra setup and eventually send it so you can just do everything at once. Also do you think my Superchips would be enough to run this combo at least for a while? I really don't feel like buying another tuner just yet.

I'm not implying that any manifold is better.....My understanding is that 03-07 manfolds are largely the same except 05-07 has a port for EGR. EDIT: The earlier manifolds (99-01 or 02) have the longest runners, no telling what kind of potential they have. The '02 HO manifold has been always regarded as the best of the WJ manifolds, but no telling how it compares to a '05-07 manifold, nor what kind of potential it has.

You will have to check what kind of TB you have to verify what you need.....03 and 04 models are a mix and match between the JTEC PCM style TB , and the newer style (and same as 05-07) NGC PCM style. The difference in TBs is that the JTEC's use 2 bolts to mount the IAC, whereas NGCs use just 1 bolt. The sensors and castings are different thus aren't interchangeable. I've been told that all HOs are JTEC, so you'd proabably want to find a manifold and TB off of another '03 or '04 HO.

The factory tune on the HO is pretty hot as is, and SC is known for not leaving much in the way of fuel on the table. The stock tune has plenty of fuel on the table. You may see better results resorting back to the 93 octane stock tune, and cutting the TM cable on the TCM to get rid of torque management. If you're bent on keeping SC, I'd buy a datalogger or a wideband to keep a close eye on things.

Quote:

Originally Posted by Scottina06 (Post 561143)
I have an extra manifold I may send you.....

I'd love to get some pics of inside the runners Scott....or even just run your fingers inside the runners to see if there are goobers or seams and if so how thick! Thats what I really need to know or see...

Scottina06 01-26-2012 05:27 PM

Re: Gen 1 4.7 (99-07) Manifold Porting Feeler/Discussion
 
I have an extra one....I will dig it out and have a look

jeeppro 01-26-2012 09:03 PM

Re: Gen 1 4.7 (99-07) Manifold Porting Feeler/Discussion
 
so is this something your doing now


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