how much of a power gain would i see with a set of ported heads and an LT4 intake on a stock 97 Z/28?

 

LT4 intake means they would have to be LT4 heads... just some FYI in case you didn't know.

As far as gains, it depends on who does them. I would recomend calling Lloyd
EPortWorks

 

well i will eventually get LT4 heads as well but i didnt know if i could use the intake by itself

 

the heads have to match the intake so save yourself the money it would cost to buy the intake and get Lloyd to port your lt1 heads and match your lt1 intake to them. ive seen lt1 heads out flow lt4 if done right and im sure he could do it.

 

There are some amazing flowing lt1 heads, however no lt1 casting will outflow an lt4 casting given the same porting, flow bench etc. there is just more meat to get rid of in an lt4 head. that said, power differences could be nil between the two depending on the amount of flow difference or lackthereof.

 

well hell i might as well do the whole LT4 head,intake,cam.ect setup then wouldnt i? shouldnt that make about 420?

 

You would need Long tube Headers to get 420-450 but is depends on the flow of the heads,LT4 is 330hp but has 10.8:1 in CP and bigger valves(i think) but Lt1 has 10.5:1.I would say 25-40hp but if you hare changing heads i would do the hole package(Long Tube Headers,Cam,Plugs,Wires,C.A.I)Saves you a hole lot of trouble

 

The LT4 intake ports are the same as the LT1 intake there is just more material so you can port it to match the raised runners in the LT4 heads. Ported stockers will outflow as cast LT4s. The only reason to consider LT4s is if you are going to have them ported and it takes a pretty mean 350 to be able to flow what they would be capable of they are really better suited to strokers.

When looking at HP ratings you need to think for a second as to how the test was done people see the 425hp number thrown around with the whole LT4 HOT package, that is on the dyno with a dyno tune headers minimal acessories etc, test the STOCK engine in the same manner and you should top 360hp. With the LT4 HOT package you mi9ght get 350hp to the wheels on a near freakishly good car where the cheaper LE1 will put down more.

Ignorance is the primary reason for the popularity of the LT4 stuff.

 

true but you have to look at what is being offered also. the le1 setup is a set of ported heads and a custom camshaft. if....and i'm just saying if...someone needed a new set of heads due to warping a stocker, cracking a head, etc etc...then the lt4 conversion could be considered. also, to put the packages on a similiar level...imagine the lt4 setup, ported, with a gm847 cam. that would be a sick pacage and be very cost effective in comparison to any le setup. Say you sell the hot cam and get some port work done you would be at right around 3k. With the le setup you still have to buy rr's, springs, lifters, retainers, etc which should get you pretty close price wise. just some food for thought for the bashers....btw i love the le setups...just dont like to see gm product get trashed.

 

Wrong, LE sets up the heads with springs and retainers and the LT4 kit doesn't include the lifters which are reuasble anyway. The LT4 spings are marginal for the LT4HOT cam so go bigger and you are replacing them(wash that against selling the cam).

LE3 is $1850 then you have to add rockers($250) to get it to the same level of parts as the LT4 HOT package, this does put it at a similar price but it will deliver as much at the rear wheels as the LT4 kit can HOPE to at the flywheel. If you want to buy LT4 heads then have them ported and get another cam and springs, sure maybe you can make more power yet but the cost of the porting will add to make that setup a lot more expensive and you are going to have a hard time making a 350 use that airflow. If someone needs to buy head then they can consider used cores or LT4s but they should not delude themselves into believing the LT4 stuff is so great.

Frankly I think you proved my point about it's popularity being due to ignorance when you tried to amke the LE kits out as costing the same amount.

The LE1 even makes more power than the LT4 HOT kit and with roller rockers would on be $1350, if you know where to get the LT4 heads assembled and with the HOT kit for that amount of money I suggest you buy all you can and start selling them for $1800 you will make a killing.
When looking at LEs site consider those are rear wheel numbers and the 425hp for the LT4HOT is flywheel and optomistic, the 370rwhp as the lowend for the LE1 is more than 425fwhp unless you have a freakishy efficient drivetrain because you would be talking only 12-13% lose.

If someone wants a seriuos stroker then LT4s or aftermarket are good choices till that stage there are better options.

 

Oh I completly agree with the fact that the LE setups will make more HP for dollar vs an off the shelf LT4 setup. However, there is more potential in LT4 heads/intake setup (you already know this) which is why I will still argue its an option for anyone building a stroker or serious motor. Sure, the LT4 NOT-cam is about as worthless as a one-legged man in an ***-kicking contest when it comes to making some good power numbers, LE setups hands down winners there. It still makes sense for people building a fresh motor while there car still needs to be used as a DD so they have no down time to send their heads off etc, cuz you can get brand new heads for cheap (comparatively)....I don't really know where I'm going with this..agree to disagree.

 

There is nothing wrong with the hotcam package $480 and I got 1.6 RRs, springs, and a cam.. and ran 11.7 with that setup on heads I ported myself (free), with a good valve job done by a co-worker on the weekend at the machine shop I worked at ($75)

 

def not...the hot cam is a decent upgrade for most consumers, but there are obviously a lot better options out there for the same amount of money, just not as readily available and as widely advertised.