I appreciate your goal to retain a "factory" appearance and I definitely relate to wanting to keep your strut tower brace as exotic sportscar level handling is the third gen's trademark. It sounds like you are doing all you can within your stated criteria to maximize plenum area. I should really practice up on my Auto Cad skills so I can create a 3 dimensional drawing of my intake idea. I know it may be more difficult to build, though I may be able to use the First Injections base to save some fabrication time. I look forward to seeing your results with your version 2 prototype.

 

That's one expensive hobby I must say.

Hey man. Thanks for allowing me the opportunity to see your intake mod. Not very many people are willing to show their engines like how you are. I'll definitely contact you prior to my arrival. By the way, do you have an extra "Fast Track" module? I hate driving down the 91. Rubberneck heaven.

 

ASE Doc I would love to see your intake idea. I have one my self using the SuperRam plenum. Something along the lines of Harrop intake for the LSX series for the runners with the bell mouths ending inside the plenum. Not sure how I could fabricate it though.

 

Fabrication is the issue. Heaven knows I do lots of daydreaming but I'm afraid that trying to actually make anything like what I have pictured in my mind is another story altogether. I am encouraged to hear that you've found someone to help you with this for what appears to be a very reasonable cost.

Speaking of the Superram, John Lingenfelter made a manifold for the LSX that very closely resembles what I have in mind. It's a cross ram (if I remember correctly) with curved runners around 12" in length and tubular plenums. The manifold's design allows for excellent alignment of the runners to the intake port entries. The large tubular plenums provide a large neutral pressure zone and effectively unshroud the runner entries. It's runners are also completely separated from the cam valley for a cooler intake charge. Ive seen this manifold here on TGO. A member was using it in his build.

Back in 2001, Lingenfelter made 580hp in a fairly mild street build using this intake on an LS6. My thinking is that something similar to this could be built to fit the gen1 sbc. In fact I think that the First Injections base might work as a starting point which would certainly make the build much easier. Though it would be a slight compromise in the design.

 

I can picture that. Here is a couple of pictures along the lines of what I was thinking. However the upper half of the runners would be in the SuperRam pizza box plenum. There would only be one throttle body at the plenum entrance. I think the biggest problem would be if one could get by the distributor.

I would hate to cup up an Edelbrock intake for experimentation. Maybe a factory one as most of it would be gone anyways. Would have to do plenty of welding as it it so a little more to open up the runner exit would be no big deal at that point.

Also a picture of a prototype SuperRam for comparison.

 

The Kinsler LSX intake looks interesting. Feeding it with cool, filtered air would be the challenge. I haven't seen that Superram prototype before. Is that from Lingenfelter's development of the ACCEL setup? Who makes the intake base pictured middle? That would make a great base for either one of our ideas. You see how the runner angles compliment the cylinder head's intake port entry. Of course hood/strut tower brace clearance may become an issue.

 

The 4 pictures on the left are Kinsler. I don't know where I got the one from the middle. The one on the right I believe is a Lingenfelter prototype for the Super Ram. When I finish Version 2 I might look into this once again. It sure would be the ultimate intake that kinda/sorta looks like it would be a Super Ram if I do it right. If one can pretty much look down the runner and see the intake valve then he is on the right track.

 

Has this car been in any major magazines like GMHTP? If not, it should be. Would give the general population a whole new appreciation for the TPI.

 

"Has this car been in any major magazines like GMHTP?"

No, no magazines at all. There has been talk and I even filled out a form telling what after market parts I have on the car. There in lies the rub. They have to get their sponsers on board to fork over money for the advertising they would get from the article. I have to many do-it-yourself parts. I will be using the Edelbrock base so that would be a plus. I do have AFR heads. The camshaft is a custom from Mike Jones so that is no good. So it goes. They would probably have to fudge some things which is not uncommon in the magazine article world.

As to progress on Version 2 I will be at the machine shop Monday to finish making up the bottom pieces of the plenum. Then over to the welder later in the week. Things are moving right along.

 

I love the build do you think it would have made more power with shorter runners and how much room do you have to bring it down with the shorter runners.

 

While I agree with that, there are some magazines out there like Car Craft and Hot Rod that do 'budget' builds all the time. While I know this is not a budget build by any means, it is in the sense that it doesn't use a plethora of aftermarket parts.

This is just too cool of a car to keep undercover. It shows what can be done if things are thought out instead of just doing the same thing everyone else does (LSX).

Glad to see you are making excellent progress on the next version. I still would have liked to see a second dyno of the first intake though.

Look forward to seeing new results!

 

Thanks guys. It should make more power with the shorter runners as I am moving the 2nd harmonic wave up 400-500 rpm for peak power and torque. RPM is your friend when building horsepower. As to bringing the runners down or shorter there is plenty of room to do it. In fact if I kept going it would be like the Super Ram.

At this point I am probably 75% sheetmetal and 25% factory casting on the plenum. The runners are completely custom made. The base is cast with a lot of welding in keys areas.

 

It makes sense that the prototype pictured must have been an earlier version of the Lingenfelter/ACCEL Superram. It appears to be one piece with rectangular runners from the plenum to the head. Of course the design we all know as the Superram was basically five pieces with the large plenum sitting atop the short 90degree sections that led to the base. The Superram base was basically a large port version of the factory TPI design.

I can certainly see how the Superram design concept, with shorter straighter runners than TPI, and large plenum could make very good power. ACCEL's offering as sold was limited for one thing by it's small CSA runners.

 

I'm curious here. So,does velocity in the runners depend upon runner inside diameter or runner length? Reason i ask is because I thought of using a set of Slp runners(they are shorter than stock tpi by almost 3/4 inch) and then making 4 half inch spacers the shape of each runner gasket.That would make the slp's about the length of the stock runners again,but i would have the bigger diameter of the Slp's at the same time. That way i was hoping to not lose any of the stock low end torque while still gaining more rpm and hp? Is this possible? or does the low end torque found in the stock runners depend upon the inside diameter of the runners? I always thought the low end came from the length?

 

Yes, runner diameter and length does play a factor in velocity. However in your case I think you would be much better off by making the inside diameter of the SLP runners at least the same diameter as the opening into the base all the way through. The SLP runners tend to taper down to a smaller cross sectional area about and inch or more in from the base. Open that area up so it is not a pinch point. Blend the plenum openings to match the SLP runners.

Runner length is a factor in torque. However cylinder filling and quality airflow play a big roll in producing torque. Again in your case I would not worry about the length of the runners that you have but concentrate on the airflow as I described above.

 

i gotcha man,but you know those bigger runners are going to move my powerband up a little,thus i may feel a loss in the lower rpm's that werent felt before. So my whole idea is to increase the length of the Slp runners by making spacers for them. What do you think? I know the AS&M runners are the same length as our stock ones,but i dont have the cash for those.LOL

 

I doubt the small change in runner diameter for more flow will greatly change the powerband enough that you'd feel the changes. Track times will show it but seat of the pants you will not. Any diameter change on those runners will help produce power beyond where it peaks but I dont think its going to change where it peaks and how much it makes below peak...it may change how much at peak but definately more beyond peak. The length still has alot of influence on where the power is made. Diameter certainly helps as shown in this thread but ONLY if the motor really needs the flow and as shown here, it takes a large tube to really push power band high.

 

So what exactly are you saying here? Lets be cut and dry. If i have 2 sets of runners and they are both the same length,but one set is bigger in diameter only. Then will the bigger set produce more power at the same rpm ranges as the smaller diameter set? Also, if the bigger set of runners does produce more power will it be at the same exact rpm ranges as the smaller set? yes or no. Not trying to be an *** here,but i just want a straight answer on it. That's all.

 

Its not a yes/no question. Up to a certain point an increase in diameter it will increase power so long as the restriction is the runners. But if the runners are not the restriction the increasing the diameter of the runners will not increase power.

Its about balance. If you had some exceedingly poor heads increased runner diameter would not help you at all. In fact it may hurt you because you'll be decreasing velocity. In such a respect you'd make more power with smaller runners.

 

Thats more of the type of answer i was looking for. So you are saying that the bigger diameter would or could decrease the velocity. That is what i thought. SO when it comes to runners, you are saying that velocity in general relies upon tube diameter and length both? not just the length right? I ask all of this cause i saw a runner/intake shootout where the AS&M runners with a ported/extruded stock base made more torque down low than the factory stuff did, and of course it also made more torque and HP up high too.

 

Its not always cut and dry tho. If the motor requires the air flow, then it will show hp/tq gains with the larger diameter runner of the same length compared to the smaller diameter runner. Larger diameter will have more flow due to larger area and less flow losses thru the pipe.

The hp/tq gains depending on how much larger in runner diameter you are talking about, will be across the entire powerband if the motor needed the air flow. The peak rpm where max hp/tq occurs will likely be either same rpm or slightly higher. Only with a significant change in area and only if the cam/heads can support those higher rpm powers will you see a power band shift.

You will likely see more power at the same peak rpms and more power after the peak rpms. The curve wont fall off as fast with the larger diameter same length runner. As the intake and heads become less a restriction, the cam is going to dictate where the peak hp and torque are made.

For your situation with SLP runners, opening them up will likely increase power with the more flow you acheive, but I dont think its going to make significant shift in powerband. I dont think the slp's can be opened up that much to see powerband shift significantly that you'd have to be worried about torque loss at low rpms. (This depends onthe cam you run tho but I am assuming street TPI setups with milder cams in the 210-220 deg range on the intake). To do that you'd need a huge change in intake setups, either way shorter runners or way larger diameter like this thread to significantly change the torque curve shape.


Depends on how big the heads/cam are on the motor, opening up the runners may only yeild 10-15hp and thats hard to notice when street driving. The track will show ET and mph changes but you will have a hard time feeling it. Heck I made 30lbft more in the mid range after dyno tune and 15-20 hp in there as well, picked up 2 mph at the track and I couldnt really tell on the street. Felt alittle better but hard to notice how much better it was.

 

With the SLP runners, you need to port the crap out of them. Measure them compared to stock, SLPs are smaller. Unless they are ported.
If your lucky you will pick up 1 maaaaaybe 2ths in the quarter mile with ported slp runners.
Now, any updates on the 2nd big runner TPI build ??

 

"Now, any updates on the 2nd big runner TPI build ??"

Back from the machine shop. All the bottom pieces to the plenum are done and need to be welded in. Before I go back to the welder I want to do so work on the interior of the plenum before the lowered floor gets welded in. I should pick up an easy 20+ cubic inches over the previous version. Progress is being made.

 

Thanks for the info man, now i wonder about bigger diameter runners but a little longer than stock! I mean i guess i can always try it out. Can make some type of spacers out of plastic or something.

 

The point of the siamesed SLP runner was to shorten the runner to reduce some flow loss from long length pipe and to help wave harmonics peak at higher rpms. They do work and shift rpm range higher since they are shorter length. Porting them out alot and going shorter will give you superram type results and if very short, it will give HSR type power bands, that will make flatter torque curves and higher rpm for peak hp.

 

That is what i already know, so my question is: How would the effect be with the length NOT shortened any and if anything , how would the runners perform with their length made even longer than stock? I think the AS&M runners are actually longer than the stock runners too aren't they? Yet , i havent really seen any dyno results of them on top of the stock base and in that test they made more power down low and everywhere really. They are out of my price range tho. THat is why i thought of a set of SLP's with homemade spacer on them to make them longer like the stock size again. I did see a test with the AS&M runners on top of a stock "ported" base. Just a thought

 

If they were just made longer the "harmonic wave tune" would come in at a lower rpm range. IMHO you would lose both horsepower and torque. You would have increased friction and less cylinder filling. The average cross sectional area would be smaller yet. Like was said above I would concentrate on opening up the SLP runners so that they are not a second pinch point hindering the air flow.

 

I understand if they were longer it would increase low end torque, but what if they were both longer and also bigger in diameter at the same time? That is what i have been wondering about all along here.

 

Longer means you will be lowering the rpm points where the harmonic wave pulse is going to hit. Also the lower the rpm the weaker the wave pulse. You have a balancing act here and you need to find the sweet spot. The factory has invested a lot of money, engineering and time into the intake to make it suitable for the heads, camshaft and exhaust.

Yes you can make the runners larger and see more horsepower but you will not get the full effect unless you do something with the exhaust system. The stock exhaust system is constipating the motor. The air that comes in through the intake needs to go out the exhaust. It is a never ending circle when searching for more power. Exhaust system, heads, camshaft and intake system. They all have to work together for the horsepower and torque level you are seeking.

Edit: I forgot to mention the all important airspeed. In the intake tract/runner most people shoot for a maximum of 300fps. Certain racing class are higher than that but they have pretty much a straight shot into the intake valve.

 

The latest update. This post and the next one will show plenum as all welded up. I have to smooth the weld and have them sand blasted to look like they were cast that way. I also will have to have the front where the thottle body bolts on hogged out to the size of my monoblade. The interior volume is up quite a bit over version 1. I believe I am now over 50% of the engine displacement. Here are the pictures.

 

Two more pictures of the plenum.

 

This really is starting to look like a Superram.

 

"This really is starting to look like a Superram."

About another 50 degrees of rotation and it would be.

 

May begin to look like a superam, but once those runners get installed, you can say "That's a hell of a TPI". Your progress is looking very good.

 

Hows this project going?

 

Quite well. The plenum and runners are virtually done. I am now working on the base. I am spending about a day per runner and have 2 1/2 runners done. I have to remove about .375"+ of material in certain areas of the runners and it takes awhile to do it right and get the cross sectional area I am shooting for. So the base should be done by next week.

 

There has been some discussion on a couple of forums regarding large port heads and small camshafts. Here is one quote from Larry Meaux on the subject.

"likewise, EFI systems has opened up or freed Head Porters
in that you can use a larger CSA intake port with EFI
and that would seem like the Trend is large CSA with smaller Cam trend"

I sure hope that bolds well for this project. Big heads and small cam for what I am doing. Making progress on porting out the base. I realized I have to "gouge" out .400" of aluminum off the roof of the port. Likewise I have to widen the walls to get the 2.76" CSA I am looking for. Finishing up the 6th port and will start working on the 7th port tomorrow. A whole lot of work involved but things look promising.

 

I have that same discussion with a lot of people. I really don't know Y everyone is afraid of large heads??? If you look at the low lift thru the higher lift numbers,generally, the larger heads flow better and more air than the smaller heads do. Don't know y anyone wouldnt want that???
I do think peolpe run cams that are "slow" or a heavy stock type rotating assembly then blame the heads..
I have been watching the guys/gals in the engine masters challange for quit awhile and it seems like the motors with the bigger better flowing ports on a given CI motor always makes better average and peak power..

 

I was going to post a picture of the 7th port I am working on as there is quite a contrast with the untouched port next to it. It shows how much material I am removing. Well the pictures did not turn out so well so the heck with that. Back to the grinding with one port to go after I finish up the 7th port.

However I do have a couple pictures of the plenum with the outside pretty much blended in. Now it only needs to be bead blasted to make it look like a factory casting. I still have to open the front to the same size as my monoblade throttle body. These pictures are also a little blurry. Just not my day for picture taking. The plenum looks better in person than in the pictures.

 

Because they listen to people with high post counts that have never run a set of good flowing larger port heads,, - lol.

 

Those guys typically run fairly large csa's, big valves, and aggressive cam shafts that give "valve motion out the ying yang" as mentioned by head porting great Darin Morgan. Works for EMC but the cam is so aggressive those motors wont live on the street very long. Valve train wont last. But the trend is there and seems to work as of late.

I dont think it would work that well on a 4500 rpm TPI build you see here, or guys not pushing past 500hp. 500hp is a cake walk with a standard 195 head with good intake and cam. No real need to push much higher. 6500 rpm+, 550hp or so, you start to see the advantage of larger heads on smaller motors.

I eagerly await the driveability of my 245cc heads and 246 deg cam. Its a decent combination of large heads, decent sized cam. 246 with .640" lift aint a small cam by any means. Hope it works as well as I think it will.

 

Well, thats pretty much my head setup (ported AFR 235s) with a bigger solid roller cam.
In my 89 formula 400 stroker I put it together (with just 24lb INJs until I broke it in) and drove it 2,500 miles on the stock chip with 0 drivability issues.

Here is mine, I'm thinkn I need a bigger cam.
Duration @ .050”: 254/258
Lift w/ 1.6 Ratio: .672/.672 (im running a 1.8 shaft now)
LSA: 110
Advance: +4

 

nothing is ever to big
its just a air pump. more in..ya get more out.

242/248 630+/- lift is a good cam for a 400+ small block. it's just the cubes eat up that size cam making it feel smaller. good street cam. for sure!

it's the top end that Dont feel the same! love cubes!

 

I liked how docile the 233 deg cam was with the 195 heads. very tame motor. I hope to have similar driveability but know the cam will lope alot harder and require abit higher idle speed. I have twin snails that do the top end feeding for me so i really dont need to go this big on cam I dont think but its the size needed for upper 6K rpm operation.

Low 240's deg for a hyd roller is a good size for most 400"+ motors I do agree. 210-220cc heads just about perfect for most street setups.

 

My car idles at 550-600 rpm, always has no matter what Ive done to it!

I don't have snails..... yet, next motor!

 

How much power you making with that roller cam and afr 235's? What port work was done? Did you take out the curly vane shape in the port?

 

Haven't had it to the dyno or tunned yet its apart now checking things and I'm doing some more little things to it.
The port work was very basic, just smoothed the port out a lil bit but left the shape they made. According to the head,cam guys that helped me on the project it should make 650-700 flwhp fairly easy.. we shall see I guess...

 

Y cant we delet our own post?? esp when they are dubs ???

 

Thats about what i'd expect, 650 hp easily. Just curious about it, trying to get an idea what mine will make all motor when I first tune it. It will breathe thru the turbine housings tho, not a straight exhaust so that restriction will kill some power...unless I make a bypass pipe which could be in the works. Not sure yet. Anyway, not to get off topic.

This port will remain straight taper right? You arent doing the taper design in this base/runners?

Let me know when you get the ls1 manifold and if you cut it down. I'd like to see that cross section shape.

 

"This port will remain straight taper right? You arent doing the taper design in this base/runners?

Let me know when you get the ls1 manifold and if you cut it down. I'd like to see that cross section shape.[/QUOTE]

That is correct. No taper until about right at the injector on the base. Then it starts to taper to the pushrod pinch area. No taper is suppose to work best or have the strongest harmonic wave pulses. Ideally the port would be straight right to the valve throat but with these heads that is out of the question. I do have the next best thing with a sleeved pushrod pinch area.

Your LS1 intake manifold should be delivered today. I want to study the intake track and check the size of the runners including the outside dimensions. If version 2 of my long tube runner project does not work out as planned I am going to do something drastic as shown along the lines of the pictures in post #405. Probably a combination of taper and wave tuning. I am shooting for 440-450rwhp.