What to do with intake for a TIII with a distributor?

[turbovanman²]

Ok, finally got to see how close the intake sits to the block and yeah, not much room. Sooooooooo, what options. I have heard of notching or cutting the intake to clear but I was thinking, might as well make a new one. What would be a good size, and being a 2.5L, would this make a difference? I figure I can move the intake out a few inches as the van has lots of room up front. I guess I will cut the runners then weld on a square or round aluminium tubing and go from there. Input would be great.

[Frank]

If you weld a new plenum on, go round and go about 3.5liter of volume. Use a 70mm tb neck and a 70mm throttle body.


Frank

[turbovanman²]

Why round?

[powermaxx]

Ok, finally got to see how close the intake sits to the block and yeah, not much room. Sooooooooo, what options.

Check with Wallace at Lonewolf. (You can't have mine :) )

[turbovanman²]

Check with Wallace at Lonewolf. (You can't have mine :) )

His won't fit factory A/C, which I am keeping, :thumb:

[Frank]

Why round?

because i say so.


it is just easier to work around and in addition, if it is going to be square you should really shape it to a size other then a box. Round is more forgiving in flow characteristics when DIY it.


Frank

[Speedeuphoria]

I think keep teh TB size ~ the same as the IC pipe your using

[Frank]

Well but the throttle plates are typically a bit smaller then the throttle body, so a bit bigger is better. Plus this is a new install, so I expect to see 70-75mm piping from his throttle body to his outlet of his intercooler. The turbo to intercooler can be 2.5".


Frank

[turbovanman²]

Hmmmmmm, really didn't think round to square would make any difference.
I will reuse my 58mm t/b and I am already running 2.5 inch lower IC pipe and 3inch from IC to t/B.

[Frank]

Dude, if you are building an intake, dont go with the dinky 58mm. You really need the 70mm to maintain a good balance of performance.


Frank

[Speedeuphoria]

I didnt realize that you had 3" from IC to TB, any way they had brand new Northstar 75mm TB's on Ebay for $57
heres what they look like, scrool down 1/3
http://forums.neons.org/viewtopic.php?t=217647&start=800
there is a wiring diagram also further down, not sure if it will work

I'm thinking about chopping the TB neck off my Indy and Tigin a 3" 90 w/ a new TB plate for a 75mm, also running a 3"pipe to IC

[turbovanman²]

Dude, if you are building an intake, dont go with the dinky 58mm. You really need the 70mm to maintain a good balance of performance.


Frank


Well, I have to maintain some streetability. I will have the opening for a 70mm just in case and use the 58mm for now.

[Garret]

Send me the Intake Simon, me and Phaxtris will make one up for you at a VERY reasonable price we'll use that 4inch pipe that we have for you lol

[Frank]

Well, I have to maintain some streetability. I will have the opening for a 70mm just in case and use the 58mm for now.

Hence why I said good balance. Trust me on this. 70mm is what you want.

[Garret]

I'd have to disagree with you Frank, 70mm is going to be like an on/off switch for throttle, good for a drag car but no way would that work on a street car.

Also on the volume I've always figured on making the plenum twice the displacement of motor or as close to that as possible. Makes for good power down low that way with short runners. Obviously with shorter runners you can use less plenum, but with shorter runners you'll lose some bottom end. Making the plenum bigger helps with bottom end out of boost

[Frank]

70mm is about 67mm throttle plate. That is only about 13mm larger then his current TB. When you add in the intercooler and piping and the fact that it is an auto, the effects are not going to be that much difference. In addition, that 70mm is going by the HP he wants to target and going by Corky Bell's streetable rule for forced induction motors. If you combine it with a plenum that is between 1.25-1.5 times the displacement, I truely believe it will be responsive, but excellent.


Frank

[Frank]

There is another problem with plenum's at twice the displacement of the motor. At high boost pressures, your flow qualities into the cylinder are approaching stall from the throttle body to the plenum and can cause in even flow qualities. May provide some awesome down low power, but its about balance.

1.25-1.50 X displacement coupled with 70mm throttle body is the balance that we seek.


Frank

[Garret]

Large or a lot of intercooler piping only has good effects on a boosted car. According to Corky my car should have no need and experince added lag from running the 2.5 inch pipes I do but when I installed them and every time I have installed larger I/C pipes on a car spool gets better and throttle response goes up(not just turbo dodges).

Real world experince tells me different on that. I tried a 58mm TB on a my 16v motor vs 52mm and the 52 provided way more driveablity and I was able to control the engine response and boost twice as well. It might not seem like a lot but it makes a difference.

The whole point of using large volumed intake manifolds is so you don't have to run retarded amounts of boost to make power on the street. Corky's book was written how many years ago and based on what real world experince? Lots of formula's and science, that doesn't always ring true in the real world. In "my" real world experince everything I have said has made a difference for me. Hell if he had two T3 intake manifolds, I'd happily build one your way and one my way and we can have a shoot out :)

[turbovanman²]

. Hell if he had two T3 intake manifolds, I'd happily build one your way and one my way and we can have a shoot out :)

As a matter of fact, I do have 2 of them, :thumb:

[Garret]

Well if you'll dyno it I'll do it

[turbovanman²]

Well if you'll dyno it I'll do it

Ok, we'll talk. Swapping the intake on these engines is a 10 min job, :thumb:

I sure don't want to go too big and I don't want to go too small, its a tough one, :o

[Garret]

Well I'll make the Frank one (Tiny wienery plenum with MASSIVE TB Boooooo)
and I'll make the Garret one (Big plenum and Normal TB YAY)

And we'll see

Just having some fun Frank

[turbovanman²]

Well my only input is this, the stock manifold will make 400-500 whp so is going larger really worth it?

[Garret]

stock turbos on SRT4s can make 400 is going larger really worth it?

[turbovanman²]

stock turbos on SRT4s can make 400 is going larger really worth it?

Not really, I don't think theres any stock turbo SRT's making that kind of power.

Anyway, my point is simply the stock intake size will easily make that kind of power so why make it larger or in your case, larger still? What are the benefits???

[contraption22]

My brother's 2.4 neon uses a 70mm TB... drivability is just fine.

[Frank]

Large or a lot of intercooler piping only has good effects on a boosted car. According to Corky my car should have no need and experince added lag from running the 2.5 inch pipes I do but when I installed them and every time I have installed larger I/C pipes on a car spool gets better and throttle response goes up(not just turbo dodges).

Real world experince tells me different on that. I tried a 58mm TB on a my 16v motor vs 52mm and the 52 provided way more driveablity and I was able to control the engine response and boost twice as well. It might not seem like a lot but it makes a difference.

The whole point of using large volumed intake manifolds is so you don't have to run retarded amounts of boost to make power on the street. Corky's book was written how many years ago and based on what real world experince? Lots of formula's and science, that doesn't always ring true in the real world. In "my" real world experince everything I have said has made a difference for me. Hell if he had two T3 intake manifolds, I'd happily build one your way and one my way and we can have a shoot out :)

I understand about real world and I only used it because it actually for once backed up what I was saying. I understand completely about what you are saying about streetability and what you were finding. I agree with you and dont deny that.

However here is why I disagree on what Simon needs. His van is very heavy. When you couple it with the tall gearing and a torque converter that is very loose at the speeds where drivability are an issue, having a larger throttle body is not going to be a problem, especially when coupled with the intake I suggested. If you were to use a 5L intake like you suggested, I think it would be very unstreetable with a 70mm throttle body. Now here is where Corky was right because it plays closely with some of the V8 guys I work with and some of the intake threads I read on TOO's old BB. If you go too large, while it may emphasis the low end of the car, the problem is that the upper end, aka higher velocities, becomes very unstable flow inside the plenum and countless people have issues with a cylinder running lean.

Believe it or not, your idea of 5L intake and smaller throttle body will probably be the same response of a 3L intake and 70mm throttle body. The advantages over the 3L are the "supposed" reductions in uneven flow and it is smaller in size and will work his distributor issue.

[cordes]

To throw my hat into the ring on the TB debate, I would suggest that the reason so many have trouble with a 52, or 58mm TB is that they are running stock electronics, or a custom cal without taking into account the different characteristics of the new TB.

I think there is a lot to be gained in drivability with even a very basic self made custom cal. The drivability especially on startup is night and day between my FWD stg 5 cal in my shadow, and the blueberry self tweeked cal in my omni... very similar setups I would add.

[Garret]

I wouldn't use a 70mm TB with a 5l manifold however

My 2.2 runs a 4.5l plenum'd intake manifold with a 52mm TB.. lots of driveabilty out of boost, in boost it pulls so hard to the redline with a mitsu turbo you'd be very surprised

[iTurbo]

Simon, why have you decided to go with the distributor over the TIII electronics (just curious)? Have you considered running the distributor off one of the cams? I think there was a guy named Edgar or John Lucas that did this long ago. I would probably give Rick D. or Wallace a call if you are set on running a distributor in the stock location.

[turbovanman²]

Simon, why have you decided to go with the distributor over the TIII electronics (just curious)? Have you considered running the distributor off one of the cams? I think there was a guy named Edgar or John Lucas that did this long ago. I would probably give Rick D. or Wallace a call if you are set on running a distributor in the stock location.


I dont' have the R/T wiring or SBEC, cals are extremely limited and also I am running a 2.5L so the dist is the easiest option plus I can retain my current block. Also, making an intake isnt' really a big deal. Wallace has an intake but it won't work with the A/C.

I might look into the dist off the cam thing, but cost wise, the intake is cheaper I would think.

[TurboJerry]

I'd put the distributor on the exhaust cam, and run the stock intake/TB. There's 500 hp with stock stuff. The turbo/intercooler/exhaust would be/is my concern. There's someone car that ran 12.20's with a 46mm TB.... Did everyone forget?

[turbovanman²]

I'd put the distributor on the exhaust cam, and run the stock intake/TB. There's 500 hp with stock stuff. The turbo/intercooler/exhaust would be/is my concern. There's someone car that ran 12.20's with a 46mm TB.... Did everyone forget?

No but its easier now to make more power with less work. Imagine how hard that engine was working. :wow1:

But thats something else to think about. :nod:

[TurboJerry]

Well, if there's 26 psi on *both* sides of the TB, How is that an issue? Maybe the turbo works harder, but I think it's *much* easier to push air then to pull it through. I really don't know the answer, I know the stock intake manifold/head/exhaust manifold will do 500 hp with little trouble if the timing and fuel is right.......

[Speedeuphoria]

I believe Robs 10 sec car runs a 52mm TB, so he should be at 500-550whp

[Frank]

Dont get me wrong on the smaller TB sizes being good for lots of power, but if you are already building an intake, then by golly, do the TB.


Frank

[turbovanman²]

Well, if there's 26 psi on *both* sides of the TB, How is that an issue? Maybe the turbo works harder, but I think it's *much* easier to push air then to pull it through. I really don't know the answer, I know the stock intake manifold/head/exhaust manifold will do 500 hp with little trouble if the timing and fuel is right.......


Jerry, see this thread, its quite interesting, :D I found that at part throttle, the restriction was huge.

http://www.turbo-mopar.com/forums/showthread.php?t=9171

[Frank]

Jerry, see this thread, its quite interesting, :D I found that at part throttle, the restriction was huge.

http://www.turbo-mopar.com/forums/showthread.php?t=9171


I wouldnt call that a restriction though! You are at part throttle because you dont want to be fast. So guess what... it is a restriction to keep you from going fast. It is only doing what you command. ;) hehehe :thumb:

[turbovanman²]

I wouldnt call that a restriction though! You are at part throttle because you dont want to be fast. So guess what... it is a restriction to keep you from going fast. It is only doing what you command. ;) hehehe :thumb:



Hehehehe, yeah, but its neat seeing the restriction that the blade causes. My van is down so haven't had chance to recheck with the larger TB.

[4cefedomni]

i need to make a custom intake for my car too i bought one of those northstar v8 75mm throttle bodies and it came with the tps and idle motor. i once drove a newer tercel and its was a tiny little motor and its power suprised the hell outa me so i had a good look at the motor and its intake looks like a header with really long runners, so something similar is what i have in mind i figure that 75mm would mate pretty well to a 3inch header collector and then i could just run mild steel tubing and weld it all up myself. any thoughts on this Frank?

[contraption22]

i need to make a custom intake for my car too i bought one of those northstar v8 75mm throttle bodies and it came with the tps and idle motor. i once drove a newer tercel and its was a tiny little motor and its power suprised the hell outa me so i had a good look at the motor and its intake looks like a header with really long runners, so something similar is what i have in mind i figure that 75mm would mate pretty well to a 3inch header collector and then i could just run mild steel tubing and weld it all up myself. any thoughts on this Frank?


Frank will get more technical with this.. but that kind of design is great for a N/A small displacement engine that needs to generate a good amount of torque, but pretty much the opposite of what we are looking for for a boosted and (relative to the tercel) large displacement engine.

[Whorse]

I was just doing some reading on the RX7 forums for my friend again, and came across something interesting. The Series5 RX7s (89-91) use an intake with 2 sets of runners that end in the same spot. They switch from one set to the other at 5200 RPM. It's called Variable Dynamic Intake. Pretty neat idea that might work for a car with a big turbo that needs a bit of kick down low.

[contraption22]

I was just doing some reading on the RX7 forums for my friend again, and came across something interesting. The Series5 RX7s (89-91) use an intake with 2 sets of runners that end in the same spot. They switch from one set to the other at 5200 RPM. It's called Variable Dynamic Intake. Pretty neat idea that might work for a car with a big turbo that needs a bit of kick down low.


2001-2003 Neon R/T's and ACR's with the Magnum engine use a similar setup, as do some other Ford and Mazda engines.

[Frank]

Actually alot of Porsche, BMW, and others use it. Even the Ford SHO used it. It is not very easy on a turbo car because of speed of sound fluctuating at various boost levels and temps.

As for intakes mentioned above, I would definently go larger then just a 3" tube for the plenum. I wouldnt be concerned at all about long runners.... make the plenum large, but manageable.

[4cefedomni]

i was more thinking about flow in this setup there would be no sharp bends the air would go straight through the throttle and through the plenum and into one of the four runnersand they would be all nice smooth curves the rest of the way in. i hate the idea of a normel intake with the air having to make that nasty 90* turn into each runner. but i'm not a physicist so i'm not sure if that even matters?

[Frank]

Well This where just some good thought comes into play. We talk about big plenum. This allows the air from the intake track to slow enough for good even distribution. Now the first thought would be to make the plenum real big. However when you do that, the dynamics of the air from the throttle body into the intake can be too turbulent. I still still stand by if you want to build an intake, you need to go 3L in volume with a large throttle body when trying to make 300+whp.

Now I think you might be talking about something like the equivalent of an equal length header like some people put on the exhaust. I have always been curious about things like that, but I dunno.


Frank

[turbovanman²]

I was just doing some reading on the RX7 forums for my friend again, and came across something interesting. The Series5 RX7s (89-91) use an intake with 2 sets of runners that end in the same spot. They switch from one set to the other at 5200 RPM. It's called Variable Dynamic Intake. Pretty neat idea that might work for a car with a big turbo that needs a bit of kick down low.


Street bikes, Ford 3.8's all use this as well as flappers in the exhaust system to produce backpressure. They really do work but as for Turbo's, I don't think it would work.

[4cefedomni]

so frank are you saying this is uncharted territory and i should try it? i figure a big plenum wouldn't be needed cause the throttle opening would be pointed directly at all 4 runners so they should each get the same flow no need to slow down.another thought i had was to put some vanes inside the plenum just little ones to try and induce a swirl into it cause i heard air moves faster when its swirling. do you think that could be beneficial?

[shadow88]

Personally, I like the square plenum, mostly because it's easier to make all the peices fit and be easily weldable.

Runner length is a tough issue with the toolbox's weight to keep in mind. Maybe around 8 inches would be my best guess for a compromise of on and off boost driving conditions.

I'd go with the biggest throttle body you can fit. I've also got a 58mm tb and about 6 inch runners and it performs just fine for on or off boost driving.

Another thing about the air distribution....your alky is injected pre-throttle body, right? This should help distribution. This is why I use 2 cold start injectors with my manifold.

I'd also go with the most reasonable sized plenum you can fit.

[Frank]

so frank are you saying this is uncharted territory and i should try it? i figure a big plenum wouldn't be needed cause the throttle opening would be pointed directly at all 4 runners so they should each get the same flow no need to slow down.another thought i had was to put some vanes inside the plenum just little ones to try and induce a swirl into it cause i heard air moves faster when its swirling. do you think that could be beneficial?

air moving in any direction other then the direction you want it is a waste unless its goal is to mix.

I would be very interested in seeing a burns stainless merge collector used as a throttle body mount and on to four runners in equal lenght fashion. If attempted, those merge collectors would be the only way of doing it right IMHO.


Frank

[4cefedomni]

thats exactly what i was thinking about the collecter so the swirl thing wouldn't be beneficial. good to know it will save me some time. i figure if i build it and it doesn't work i'm only out my time and some mild steel tubing and i have a stratus manifold that i could still use but i would rather go for extreme performance and i think this style of intake is the ticket. my thoughts were 3inch intercooler piping, 75mm throttle body which i have, and a 3inch collector going to the runners and i'm still not sure on the runner size. but i was trying to keep everything the same diameter so it will maintain a steady flow flow all the way in.

[Frank]

Well if you were to attempt it, it will be very important to model your collector like the following picture....
http://www.burnsstainless.com/MergeCollectors/4into1base/a_base_4-1.gif

Very important for even air distribution and quality of flow.

[4cefedomni]

for sure thats exactly what i had in mind just like a header collector

[turbovanman²]

for sure thats exactly what i had in mind just like a header collector


Funny you bring this up. When the Quad 4 first came out, it had a tubular intake, with a collector like above, then they switched it out to a cast style with no collector like above and it made more power? :eyebrows:

[22mopar]

Ok, finally got to see how close the intake sits to the block and yeah, not much room. Sooooooooo, what options. I have heard of notching or cutting the intake to clear but I was thinking, might as well make a new one. What would be a good size, and being a 2.5L, would this make a difference? I figure I can move the intake out a few inches as the van has lots of room up front. I guess I will cut the runners then weld on a square or round aluminium tubing and go from there. Input would be great.

simon, how about relocating the distributor. years back, I built a carburated Quad 4 and used a 2.2 dodge distributor. I fabed up a bracket and ran it off the cam. being your are a pretty handy guy, I would think you could give that a-go.

[puppet]

Without a plenum the engine will choke the air through the TB on each piston stroke. The air in the plenum smooths out the flow and helps the air gain density.

I don't believe that a single TB can keep up with four individual runners at higher rpm's without a plenum.

[4cefedomni]

well my throttle body is the same diameter as my intercooler piping and the collector so it shouldn't "choke" it through

[TurboJerry]

Jerry, see this thread, its quite interesting, :D I found that at part throttle, the restriction was huge.

http://www.turbo-mopar.com/forums/showthread.php?t=9171

I was only speaking of WOT. I *want* restriction at part thr. (The gas mileage is much better) You are seeing a bigger tip in response because of the bigger window at the same opening. All I'm saying is that I'm *not* building an intake, and I don't need a 100mm TB to run 11.50's. But, I am agreeing with anyone who says to put a bigger TB on a custom intake. If I was, I would use a 75 to 80mm. I actually think a '93 Jeep 4.0 TB is the best one because it plugs right into the IAC and TPS connectors, and if you look more carefully, they even have ones with the bolt on throttle arm for your ATX needs. I'm not trying to bag on anyone, I just think the T-III is a great thing to start with, and I have no need to do anything *crazy* to get 500 hp....... Just the four B's........ I also love the look on peoples faces when there's a stock engine under the hood of a 3200 lbs car running deep into the 11's.

[johnl]

Simon, I don't know nuttin bout hybrids so maybe this is a wacky idea -

Since, at this stage of this project, you reasonably want to keep it simple and since TurboJerry makes the point that stock intake will run just fine -

why not just put a 1/2 inch phenolic/garolite/arboron spacer between the head and the manifold? Might lower intake manifold temperatures too.

[whywoody]

You could build a manifold where it's intake flange/TB mounting surface un-bolted.Make this piece as large in area as you need,so you can un-bolt it and upsize/down size TB's easily.That way you could experiment a little,until you found the right one.
I built a similar piece for a project before,from steel,that just relocated the stock TB,onto an alternative manifold so it would fit the new engine bay.Worked great!

[turbovanman²]

Simon, I don't know nuttin bout hybrids so maybe this is a wacky idea -

Since, at this stage of this project, you reasonably want to keep it simple and since TurboJerry makes the point that stock intake will run just fine -

why not just put a 1/2 inch phenolic/garolite/arboron spacer between the head and the manifold? Might lower intake manifold too.

That could be an idea but I figured the stocker is a restriction so why not fix it properly, :thumb:


You could build a manifold where it's intake flange/TB mounting surface un-bolted.Make this piece as large in area as you need,so you can un-bolt it and upsize/down size TB's easily.That way you could experiment a little,until you found the right one.
I built a similar piece for a project before,from steel,that just relocated the stock TB,onto an alternative manifold so it would fit the new engine bay.Worked great!

Thats what I was planning to, have it so I can mount a 70mm TB and an adapter plate to bolt up my 58mm unit. I can also relocate the TB so its a better fit to the IC outlet, :D

[Nemesismachine]

Dude, if you are building an intake, dont go with the dinky 58mm. You really need the 70mm to maintain a good balance of performance.


Frank

70mm? I would hope that youre running a bigger turbo, forged internals, bigger injectors, higher boost, just bigger everything. Otherwise you'll just end up with 10mpg. :)

[Whorse]

Hahah, he is.

[turbovanman²]

70mm? I would hope that youre running a bigger turbo, forged internals, bigger injectors, higher boost, just bigger everything. Otherwise you'll just end up with 10mpg. :)


I am, :thumb: