irocbirdbuilder

So i spoke to soon saying i was doing no more mods until i build my 406....i lied, i found a shop out here that comes highly recommended by the guys at burt chevrolet and alot of guys i know with porting work done by them. I called to find out about the tpi head swap and we talked for a good hour.

He said to bring in my heads, they need a valve job anyway since i smoke on startup 175 bucks then he "pocket ports" the intake side of em a little, he sadi he gaurantees me 30 horses on a dyno, if they dont make it you bring em back and he'll work em until they do then refund the dyno cost and gaskets. Total comes to right about 500 bucks. He said the edelbrock manifold is good for maybe 8 horses or so and then to do some porting on the tbi unit. Guy has been in business for 25 years and all his shop does is strictly heads. So hopefully next week i can start tearing down the top end to get em into him since i'm looking at 2.5 weeks to do the heads i'll get it done and be able to then do my interior and have it up and ready for show season. Like he said you can go out and spend 1400 bucks on nice heads and still are lookign at gains of 30-35 horses.

Dewey316

you get 30HP without changing anything else from 'pocket porting' on the swirl-ports, and I will pay for you heads.

I don't want to burst you bubble, but with everything else holding these motors back, cleaning up part of the runner on the head won't get you a whole lot. you are still limited by small valves that are shrouded by the cyl. walls, the swirl part of the heads that kills any flow, and what is possibly the smallest cam GM has ever used.

Avenger007

your paying $500 to have this all done? You know you can get a set of new vortecs machined for at least .510 lift to your door for that same price, assembled. I think this is a bit of an oxymoron...swirl ports and "hope" in the same sentence.

ShiftyCapone

iTrader: (7)

I agree with what was stated above. The LO3 has so many bottle necks that heads won't help. It is a waste of time, money and energy to bother porting them. Check out the reasons above in the sticky to confirm.

sunset92

... pessimists....

Dewey316

nope....

... realists...

xpndbl3

iTrader: (5)

now do the heads, headers, exhaust, cam and intake and free tbi mods....and we have 30 hp

Fast355

iTrader: (2)

Swirl ports are trash compared to even a tpi head or 305 HO head.

irocbirdbuilder

Not being an *** or anything but why am i going to listen to guys on here over a guy who comes recommended by a ton of people and has been doing it for over 25 years ya know?

Everyone keeps saying go vortech heads but some of us have to comply with emmisions, i woudl do the vortech swap but they WILL NOT pass emmissions out here and that came from the guy at gm.

Until i see pics and dyno sheets showing your pocket ported swirl ports did nothign i'm staying open minded, YOu say no they are junk and even porting them does nothing, i have a guy that say yea you will have 30 horses by doing this i tend to lean towards his poitn of view since he specializes in heads. He says he has done l03 swirl port heads and has and will get 30 horses out of em. ANd it will stay emmissions kosher

25THRSS

That's fine and dandy, go waste your money. What do we know, hell, we only specialize in these cars that we own. At the very least, ask him what the flow #'s are before and after.

irocbirdbuilder

I guess what i'm getting at ts on here it is this way or no way....Everyone says no its a waste but no one has had any real facts or items proving it did or didnt work, Its essentially the same as everyone saying throwing roller tipped rockers gets you 20+ horses, not low end they dont, thats real world we ran em on our race motors and they were for high rpm apps, and we got 15 horses above 7000rpm. Everyone says it cant be doen but no one will prove it?

25THRSS

It's common sense, the "swirl" blocks half of the air practically. Why spend all that money when you can buy better heads for the same price or less? Yes there is room for improvement, but there is far more potential in most other heads. Honestly I am curious though. I would like to see you have them ported just to see what you could get out of them, but make sure you get the before and after flow #'s.

irocbirdbuilder

25th i get what you are saying, the porting is on the obstruction part of the head..he said they are not a performance head but can be improved, i guess if i do this though i'm going to have to dyno before and after anyways, i wanna see people that have done it though and see what happened

25THRSS

Dyno #'s are good, but there are too many variables to consider. Flow #'s are a better comparison IMO. Good luck.

TPI-454

This is where I agree. I'm sure this guy is very experienced, and I'm sure he knows what he's talking about... I mean heck, any head can be worked.

But for the money you're going to spend, I would rather just pull a set of TPI heads from the junkyard, get yourself a valve remover & porting kit (I'm sure you have the drill already). Re-seat those valves (its a good wrist workout, isn't it guys), get yourself some umbrella valve seals, and do all of the porting work yourself.

You'll spend less than half of what he's going to charge, not including you're own labor of course. Not to mention, for the extra money you'd save, you can go ahead and pick yourself up an LT1 cam, install it, and still be under the $500.00 mark....

Good luck with whatever route you choose!

Dewey316

Yup, I guess none of us know anything. None of us have spent money doing mods we wish we hadn't done. no one on this board has modified their L03 like this before... Congradulations you are forging into a brave new world.

best of luck, you just found my ignore list.

BMmonteSS

ok lets ASSume that he does get 30 hp out of your heads. Which I can believe because those heads suck so bad that any work you do is going to help them. You now have 500 bucks wrapped up in maxed out heads that won't even come close to flowing with some better stock heads. You can take that 500 bucks and sink it into vortecs and probably make an honest 30-50 hp more and still have room for improvement later on down the road. There are ways to make vortecs legal, but we're too dumb around here to know how. If you factor in the cost of a new intake for the vortecs, you could could buy iron lightning heads and bolt your stock intake to that. They run about 850. These heads flow about 15 to 20 cfm more than vortecs. Bottom line there are much better ways to get 30 HP.

kdrolt

AFAIK someone already HAS proven it.... but his posts (which include flow bench numbers, dyno numbers, and track numbers -- all in a before/after sense) get ignored because he's in a severe minority.

Look for either JPrevost's post on swirl port heads and why they need to go, or look directly for Dyno Don ('s) post on porting the 193 casting number head (as used on the LO5). The swirl port heads have deficiencies (in stock form) but they can be cleaned up with little work and they are not nearly as bad as the TGO hand-waving says they are ---- IF a mild porting job is done on them.

Anyway, look for DD's posts and then take what he got for gains, compare it to what people HAVE MEASURED on the dyno using similar engine specs as DD using other heads, and add a column that includes the costs for each approach (assuming new or used parts). I suspect the result will be that you can get more from the Vortec heads than you will from the ported swirl heads, but you'll pay more. Also keep in mind that no matter which approach you take, you will have to deal with reprogramming the ECM.

Dyno Don

iTrader: (7)

[He said to bring in my heads, they need a valve job anyway since i smoke on startup 175 bucks then he "pocket ports" the intake side of 'em a little, he said he guarantees me 30 horses on a dyno, if they dont make it you bring em back and he'll work em until they do then refund the dyno cost and gaskets]

The biggest gains are on the exhaust side.


To save you the time searching:
https://www.thirdgen.org/techbb2/sho...hreadid=177465

Fast355

iTrader: (2)

Swap to a TPI head as they bolt straight on and look exactly the same (no smog issues). If you want spend the same money on the TPI head. Port the TPI head and you will have 50 hp or more. I had the swirl port 193 on a 350 swapped to the TPI 081 305 heads that I ported and would never look back.

BMmonteSS

http://chevyhiperformance.com/techar...98/index4.html

If you go to that link you'll be able to easily see what alot of better stock heads flow. You'll see that if you compare the flow numbers dyno don got to the the l98 heads (i think the aluminum and iron heads have the same ports) you'll see that once ported the swirls have the same flow. So 500 bucks for the same flow of l98's. The exhaust side on the swirl ports are actually great out of the box for stock, and he picked up big gains with porting, but you can see that it won't do any good since the intake side still sucks. From what I've seen and read 5 cfm is worth 10 hp, which coincides with what don saw, so vortecs have 35 cfm more flow on the intake side even after porting compared to swirls. You'll have to remove all the restrictions on the intake and exhuast side of things to relize the full advantage of all the flow.

Damon

Exactly. The swirl port intake issue is a red herring.

I am NOT a professional head porter. I screw around a little and make the ports look how I think they should look when I feel like picking up a die grinder on rare occasion. They I bolt them on and go run them. I'm a modestly experienced bumbler.

My expereince is this: If I port the exhaust side, lousy job though it may be, the damned car almost always runs significantly faster. Then I do the intake side and I don't pick up much more.

Conclusion: Almost anything you do to the exhaust side will make it flow a lot better. Almost anything you do to the intake side won't help unless you really know what you are doing. Porting an exhaust is relatively easy to get good results. Porting the intake requires real skill.

JPrevost

All power in a SBC is in the exhaust ports of the heads. The whole reason dual pattern cams came about was to try and offset the imbalance.
I don't down 30hp and if all you want is 30hp then go for it. Question though; do you plan on keeping this car for a while? If so, the speed bug will bite and when it does you'll be looking at a maxed out head as your bottle neck again.
Vortec heads CAN be emissions legal if you add EGR, how do you think the trucks did it?
The reason I like vortec heads is for their overall superiority in terms of efficiency and engineering. They have relatively small ports and tons of potential. The combustion chamber is as advanced if not more so than the aftermarket (superior quench to older heads), raised runner intake ports that give the flow a straighter path at the valve, and they're cheap. They also respond to exhaust porting like you wouldn't believe.
Here is a link to my swirl port bashing, lol.
https://www.thirdgen.org/techbb2/sho...hreadid=268064

irocbirdbuilder

Ok guys thanks for the facts, my dad called the guy today making no relation to me and was told the same thing that they could be done up for 30 hp. I'm going to give the motor guys at burt chevy a call and find out about the vortechs more and how to make em smog legal. I basically plan on getting some power for now since the 406 is going to be all new parts, nothing i am planning on swapping from this motor.


""Yup, I guess none of us know anything. None of us have spent money doing mods we wish we hadn't done. no one on this board has modified their L03 like this before... Congradulations you are forging into a brave new world.

best of luck, you just found my ignore list.""'

I think thats a little severe dewey, i see where you are coming from but you have to look at my point of view ya know, people saying no it cant be done makes me want to do it even more. And when someone says it can be done it makes me really look into that way of doing it since i dont have 1500 to slap down for a set of new heads,

Fast355

iTrader: (2)

Take the intake valve out of one of the heads and look below it. Open a TPI head up and look at it. The swirl ramp blocks more the 1/2 the port and creates severe flow blocking turbulence. Hence the name swirl port. It has one function to help atomize the air/fuel mix. GM used it for a very slight fuel economy improvement and emissions. I am not saying that a swirl port head cannot be improved upon but I just can't see doing it when I can get 305 TPI heads cheap. I went from 193 swirl ports to 081 TPI heads in my van and the difference was night and day. The TPI heads will boost airflow through the intake side. I paid $50.00 for my pair at a wrecking yard with under 100,000 miles on them. I used an autozone loaner spring compressor and reworked them in my garage. You could sell your swirl ports for $50.00 and have the TPI heads for essentially free. FYI I sold the 193s to someone who needed a good set of stock heads for $100.00, pocketing the $50.00 I used to update to Z/28 springs. Get your TPI heads rebuilt and pocket ported and you could pick up even more horsepower. If the porter can make 30 horsepower out of a swirl port think of what he could make out of a TPI head. TPI heads are a win, win proposition IMO. Here is a DD2000 of a Stock swirl port vs. a stock 305 TPI head on an otherwise stock 305 TBI.

Swirl Port
RPM HP TQ
2000 118 311
2500 145 304
3000 168 294
3500 178 267
4000 174 229
4500 159 186
5000 131 137
5500 95 91

081 TPI Heads

RPM HP TQ
2000 120 314
2500 147 308
3000 173 303
3500 188 283
4000 194 255
4500 192 224
5000 174 182
5500 144 138

Notice how it is 16 HP peak to peak but is 33 HP @ 4,500 and 43 HP @ 5,000 and all the way to 49 HP @ 5,500 . It is probable that given the same work the TPI head will make these numbers even farther apart. This is on a completely stock car. Add headers, open up the TBI, put in a LT1 cam, retune the ECM and see even more HP.

1997 F-body LT1 cam, Headers, TPI Heads

RPM HP TQ
2000 125 329
2500 156 328
3000 189 330
3500 218 328
4000 241 317
4500 254 297
5000 254 267
5500 237 226

1997 F-Body LT1 Cam, Headers, Swirl Ports

RPM HP TQ
2000 121 319
2500 150 314
3000 182 318
3500 207 310
4000 219 287
4500 215 251
5000 199 209
5500 171 164

The difference peak to peak is 35 HP. At 4,500 the swirl ports are down 39 HP. At 5,000 they are 55 HP behind. At 5,500 there is an astonding 66 HP. Port the TPI heads and the advantage will increase over the swirl ports again.

To me reworking a TBI swirl port is not worth it. I don't know but numbers don't lie in my opinon. Why not see if the machinist will swap your TBI head and maybe a few $ for a set of 081 TPI castings.

irocbirdbuilder

Wow thanks fast, that is the evidence i was talking about, like i said above i will find out more info on making the vortechs legal and also look at finding some tpi heads if with headers, tpi heads and lt1 cam there is 66 horses more at 5500 then figure in what 20-30hp with porting, that is crazy and you my friend might have just changed my mind about reworking my heads thank you

Fast355

iTrader: (2)

For those who have not seen a swirl port vs. a regular port check this page out. http://www.customclassictrucks.com/t.../0405cct_head/

Fast355

iTrader: (2)

Don't forget you have to be able to make changes to the chip calibration to take advantage of the increased airflow. This is perhaps the one mistake that most people who mod TBI cars makes. I'm not even going to get into the fact that edelbrock makes a TBI intake, holley makes a 670 cfm TBI, etc.


By the way its not the TPI system that makes the TPI cars faster than the TBIs. It is the cam and the heads.

kdrolt

That ramp blocks less than half the port because the port is deeper on the long side than other GM heads. AND you are talking about the geometric area which doesn't necessarily mean it blocks half (or slightly less than half) of the airflow. You are assuming, incorrectly, that because the port has the obstruction on the short-wall side that the volume flow will be obstructed. Got any of Vizard's books? He discusses the fact that most of the airflow is along the long wall of the port, so obstructing the short wall has a small effect on airflow, especially at low lift. That's why isn't not that important to work the short wall when porting heads because there isn't much flow there.... at least as it concerns a street-driven dual-purpose ca.

BTW turbulence is a good thing when it comes to two-phase combustible flow.

*snip*

I'm assuming that you took the flow numbers for each of the stock swirl (187) and TPI (081) heads and ran them into DD2000. What's missing from it is that DD2000 only knows what the flow rates are for a given valve lift --- but it knows ZERO about the swirl. So don't draw too many conclusions abou the comparison you made from using DD2000 because the math it uses, under the hood, is very simple. If you want real-world comparisons, find an engine/cam/intake combination on a 3rd gen Fcar that mimics what Dyno Don had. Compare his flow numbers (there are TPI head flow data on TGO), as well as dyno measurements and track timeslips and see hiow close or how far apart they are. That's a much better way to see just how good (or bad) the swirl port heads are.

Example: Dyno Don got 210 rwhp before the swapping the heads, and 250 rwhp after. 250 rwhp with 193 casting swirl port heads, headers, LT1 cam means more that 300 hp at the crank. That's a lot higher than the numbers you have here from your DD2000 exercise:

Finally, what did Dyno Don run, 13.7 @ 102 mph after the swap? (correct me if I have this wrong). What does a similarly equipped (LT1 cam, headers, TPI, same gears, 700R4) 350 run with TPI heads? The difference between ported swirl heads and others, isn't nearly as great as many people here believe.

BMmonteSS

Actually if you look at the flow numbers you'll see that ported swirl ports flow exactly or pretty close to most stock SB heads. Which is great, except for the fact you now have tons of money or tons of time wrapped up in heads that are tapped out. No one said you can't gain power from porting swirld ports. Every one said it was a wast of time and money because there are way cheaper and better alternatives out there. Next time you ask a question give everybody the benefit of reasonable doubt and don't call them all liers because they don't think what your doing is the best route.

Avenger007

i agree with above. I think we need to get past the point of being able to gain power from swirl ports. The evidence is there...however is the admission price worth it considering better heads will get you there and further for less $$ & time.

Btw Fast355 by saying:
"its not the TPI system that makes the TPI cars faster than the TBIs. It is the cam and the heads."
do you mean faster as in 1/4 mile? I believe hp gains are definately shown putting a TPI intake on an otherwise stock TBI car. I think its the combination of all 3 making them faster cars. I know that a TBI car will still pull hard down low but the 25-30hp diff from the intakes makes a difference also

Fast355

iTrader: (2)

I have done the dyno and run on the track to find the difference between 193s and 081. I used numbers that I actually recorded on a machinest buddies flow bench, he is the one that taught me to scientifically port heads. Atleast the 193s suck. I have played with porting swirl ports and did gain some power. I did however have more power with stock TPI heads than the ported TBI head. The best I could run was 15.6 @ 83 with ported TBI 193 heads. With unported TPI heads I ran a 15.2s @ 88. With the Ported TPI heads I am running 14.8s @ 94ish. Keep in mind I am not running a TBI setup on it currently although I have experimented with trying to run it with unfavorable results.

The TBI system might be a little slower in the 1/8 but it is quicker in the 1/4 atleast on a stock 1992 chevy shortbed truck with a 350-700r4 and 3.73s. Ran a 16.2 @ 83 with the TBI and a 16.4 @ 77 with a TPI. The tpi was faster in the 1/8 due to better low speed torque and pulls his boat better but the TBI was faster when the truck was empty.

irocbirdbuilder

Now were getting into the facts i really want, i guess i misunderstood everyone saying it is a waste of money for little power compared to you can but theres other alternatives, my buddy out here in co has a 89 rs 5.0 tbi aith all the ultimate tbi stuff, headers, no cat, no emmissions stuff, ported tbi and ported and polished stock tbi heads and he is doing 300 to the wheels, i believe it is also cammed a tad, he said the same thing that he got 30 horses out of the heads being ported, to get a set of tpi heads and have a valve job done and porting i'm looking at the same price, i'd rather take heads i know are in good shape and have them reworked,

Everyone is saying i wont get the power or gains liek the head guy is talking about, so i'm gonna do it anyways I think it can be done i have talked to others with similar combos in colorado, everyone says 350 injectors are a waste on a 305 yet guys out here have done it and get power from it, same with the heads, so if it fails and i get little power then i'll know its a bad combo, but i dont know till i try eh? GOtta remember too i'm at high altitude, the car responds different to certain mods up here then tehy will at sea level, so what teh hey, doesnt hurt to try right?

25THRSS

Your buddy does not have 300 rwhp. The 350 injectors will only help you if you need the extra fuel that the 305 injectors will not support, otherwise they are a waste.

irocbirdbuilder

Oh so i wasnt standing next to him during a coloradof-body dyno day when he pulled 300 horses at the wheels, my bad i forgot you knew everything there was, he gained power off 350 injectors whats it gonna hurt to go to a bone yard, spend 15 dollars on 350 injectors and see what happens?

Fast355

iTrader: (2)

I have used 350 injectors on a 305 and it makes a difference just as I picked up 20 hp @ 5,000 rpm on my built up 355 by using 454 TBI injectors. The stock calibration was so lean that with my mods it leaned it way out. I was getting about 15:1 air/fuel ratio at WOT. I could actually let up off the floor a little let the computer go into closed loop and accelerate faster. Just that simple change will make a huge difference if your prom chip isn't optimized for your changes.

25THRSS

I'm sorry I gave you advice. Now that I know you will not listen to anything except what you want to hear I will not attempt to help you out. It's seems as though you aren't using common sense and/or you are lacking imperative knowledge on the subject. If the 305 injectors are meeting your needs and providing the wanted AF ratio, then please explain to me why you would want to put larger 350 injectors on your car. They will provide more fuel causing you to run rich and you will lose power. You can put them on all you want, as it seems you get snippy when anyone tries to offer you common sense. BTW, your buddy did not put down 300 rwhp with the mentioned mods.

irocbirdbuilder

WEll i'm trying to keep an open mind about the setup i'm looking at people here say it doesnt work, yet i know poeple who have doen it and it worked for them, all cars respond different in different climates and altitudes so what doesnt work where you are might work up here, His machinist said 350 injectors would help out with the combo he already had and it did, thats all i'm saying i'm taking all the info everyone posts in and considering it before i do this stuff. I'm not going to get into an argument on what my buddy did or didnt dyno at, so i'll leave it at that and see if i can get him to scan me his dyno sheet. ANd a full list of mods

ShiftyCapone

iTrader: (7)

Agreed. Even the most heavily modded 305 TBI is only putting down 260 to 270. Trust us on the 350 injectors. The best TBI tuners in the world (which are here on TGO) will tell you the same thing. I will take JPrevosts and Deweys words over anyone in the world when tuning TBI.

90RS305

Except for me, right? Seriously, I've been reading a LOT on the tuning aspect of fuel injection, and after a few hours and a couple bottles of tylenol, I came to the conclusion that even with TPI heads getting 250 at the wheels is nothing less then impressive... Shifty is right, there isn't anyone in this world that knows more about Throttle Body Injection then our fellow kin here on TGO... :hail:

Bruce (90RS305)

BMmonteSS

I think the problem with this thread is that iroc builder is not completly reading the post. If you read closely every point your arguing is a mute point.

The argument about the injectors is this. IF your 305 injectors are feeding your motor than the mere act of installing your 350 injectors will do nothing. Of course if your lean then of course adding more fuel will help.

The argument dealing with the 300hp 305 TBI is this. Your buddy did not make those numbers with JUST the mentioned mods, he had others, probably bigger displacment.

You seriously need to drop the attitude and read in to what people are saying. This is the best site on the net for TBI specific info. You won't find any better place period. If some one says it won't work, ask why it won't and we'll explain it to you. Don't call BS and get snappy, people don't like that.

irocbirdbuilder

Ok this will be the last "argument" i make since i want it to get back onto the combo here, i am reading every post, over adn over, my buddy has more mods than i listed off teh top of my head but he IS FOR SURE still running the 305 shortblock, but he doesnt have heavy cam or anything like that, i will contact him and get a full list of mods though.

I understand everyone here knows stuff about tbi cars, i am trying to take in what people are saying will or wont work here and compare that to what people in co have done and what shops tell me has worked for customers in the past, everyoen says it cant be done yet no one has given me really good evidence that tells me otherwise. I think everyone here is too into doing things one way, and i'm not getting cocky since thats not a bad thing example, ultimate tbi, next to everyone on here has done them and they work so thats a good thing but from what I SEE THROUGH my eyes is people tend to stay with a certain line of mods and dont really take it the next step adn go ok this is what numbers i want to hit so this is what i'm going to do. I'm not doubting anyones opinions...i'm taking it all in so i can come to a conclusion of what i need to do, I'm not motor stupid trust me i know how this stuff works, i've been doing it with my dad for years and we have built many cars into the low time ranges ie 10.3's, 10.9's,11's and so on, its just figuring out the injection and what will work best at my altitude and with the rest of my stuff.

Fast355

iTrader: (2)

I dynod mine using a TBI on it. I have not dynod the Q-jet on it. It runs alot better on the bottom end than the untuned TBI.

I was making 275 RWHP with a totally untuned TBI system but it is a 350. I did have quite a few mods though. 350 with ported 305 TPI heads, LT1 roller cam, 1 5/8" x 3" full length headers and 2 1/4" dual exhaust without cats, edelbrock performer EGR intake for 87-95 heads, TBI-Carb adapter, reworked TBI (ridge removal, double injector tower gaskets, raised fuel pressure to 17 psi, early model 454 TBI injectors, 6* initial advance at the distributer. I did however still have a lean condition in the mid-range and was very rich on the bottom end and at idle. It was so rich I was getting 9 MPG and could barely idle. The BLM & integrator readings were at a constant 100 on the bottem end and came up to 140ish@ about 2,500 rpm. I went back to 350 65 lb/hr injectors and lost the 20 HP due to running very lean. Couldn't get it right without spend alot of time and needed if for daily driving so I went back to the stock 305 CCC Q-jet.

Fast355

iTrader: (2)

Forgot to mention that I also had the CFM power plate and the chili bowl thing from Hypertech. Both of those are now on my 2.8 blazer.

ironroad9c1

335 you should check with brian over at www.tbichips.com he did mine and it was a wonderful improvement over untuned setup ,i to have the 350 with lt1 cam ,305 ho heads ,headers,and 2 1/2 duals , for 95 bucks ,i get the chip,shipped with 3 more free tunes avalible if you need it. i just need to find someone to do a data log so i can see just where i'm off,but now that i went from a 160 tstat to a 180 it seems to be better on the top end i'm almost sure that it wasn't making it to closed loop.with his tune i was able to set the timing back to the stock 0 Degrees where as before i had to set it atleast 16-18 degrees to even get it to idle .

now i'm telling you guys don't waste your time on these swirl ports your just better off just either getting some vortecs (thats the best deal) or for a buget build up ,do a set of 58cc 305 heads with a edelbrock 4brl intake and a set of headeds and lt1 or slightly bigger cam ,just be sure to replace the valve springs,i have $400 in my swap and it runs like a scalded *** ape ,can't wait to dyno it to see what it gets .

Dyno Don

iTrader: (7)

Here is the after picture:

Edit:
Just wondering outloud (with tongue in cheek) does anyone see "the intake port half blocked" in this picture?

Fast355

iTrader: (2)

Looks like you just cleaned up the stock intake port somewhat then went for the major gains on the exhaust. Just like everyone else.

irocbirdbuilder

Well i havent had time to give gm a call but i was looking through summit tonight and they have the vortech manifold listed as egr compatible, does this have the mounting pad for the egr valve? it says egr must be plumbed from exhaust manifold, so then i pulled out teh chevy hiper and there egr valve is right up front....never saw that before, if thats the case that i can infact have vortechs emmissions compliant i will take that route as i have seen very nice gains out of that setup

ironroad9c1

yes the egr feed into the intake from the stock front drivers side location ,as if you where installing the manifold off a vortec truck using the vortec manifolds,there is a pipe that runs from the driver side exhaust manifold up to the intake that the egr gasses go though instead of comming out of the intake mounting surface of regulaer heads and the egr works just the same ,if you have smog headers you can plumb the egr pipe from the air injection tube,

ironroad9c1

thats not the biggest part of the prob there don ,post a pic of the intake runner