Big intake stock head.

[thedon809]

Lengel plenum + 1/2 spacer to a stock 2 piece lower that was crudely blended to gasket size while on the engine. 60mm Jeep throttle body. I can say, without a doubt in my mind that the head is NOT the cork.

My car has a t04e 50 trim with stage 2 turbine and .63 housing. It always had a pretty bad lag. Like your dragging an anchor. The classic, nothing is happening and then boom, 15psi and it's moving decently. Kind of like a switch.

With the new intake setup, the engine feels free. The power delivery is so much more linear and smooth. It feels like a modern turbocharged engine. I'm running like 8psi and it feels as fast as the old setup at 15psi. So far, zero downsides. Drivability is excellent. Even after eliminating the AIS.

[cordes]

I'm confused. You're using a stock head with a highly modified two piece and big TB, but the head is not the cork?

[wheming]

I'm confused. You're using a stock head with a highly modified two piece and big TB, but the head is not the cork?I read it to mean, [the head] was not the cork with the previous basically stock configuration, except for the turbo upgrade.
However, Alex you may find now as you turn things up, the head may become a limiting factor.

What are your goals? Sounds like you just woke it up quite a bit! So congrats. The power of 15psi at only 8psi is a nice improvement.

[thedon809]

I'm confused. You're using a stock head with a highly modified two piece and big TB, but the head is not the cork?Since for as long as I've been into these cars I've read that there was no point in upgrading the intake manifold if you have a stock head. They said the head was the cork BEFORE the intake. I'm not saying the heads not a cork lol. I'm saying it is absolutely worth upgrading the intake and throttle body on a stock head car. Even if you were running a 2 piece

I read it to mean, [the head] was not the cork with the previous basically stock configuration, except for the turbo upgrade.
However, Alex you may find now as you turn things up, the head may become a limiting factor.

What are your goals? Sounds like you just woke it up quite a bit! So congrats. The power of 15psi at only 8psi is a nice improvement.This was more or less just a test to see what a big plenum would do on a stock head. I can't go crazy anyways because the car has a stock t1 engine. Im trying to find a bare common block to build right now.

[83scamp]

Congrats on the noticeable improvement!

But I will concur with Wayne, I think once you start turning it up more, you will see the restriction of the stock head. Decent porting, and +1 valves will make a dramatic improvement. I like the +1's more for a clean cut on the valve seats, than any huge improvement in flow. I know the difference in power between my stock 2.5 T1 in the Daytona, and the modded one in the Scamp are night and day. And I'm running a stock T1 SMEC & injectors in the Scamp still on 10 psi. So it's not like I've done a bunch of trick tuning to get the power. Now, I know the weight difference between the two accounts for some of that "feel". But with the ported 2 piece, 52mm TB, ported head, and ported exhaust, the 2.5 in the Scamp pulls way harder all the way to 6K. The Daytona is done by 5K.


It's been talked about many times before, but these engines like efficiency of flow, more than shear volume of flow. There is a difference. You make the air flow efficiently through these engines, and it will amaze you the power they can produce.

[thedon809]

It's been talked about many times before, but these engines like efficiency of flow, more than shear volume of flow. There is a difference. You make the air flow efficiently through these engines, and it will amaze you the power they can produce.That's all engines really.

[tryingbe]

I had Asa's BMF intake on a stock cylinder head, I wasn't impressed.

In my experience, below 4000rpm there is not much difference between a stock head and my FM stage 3 ported head. Once you pass the 4000rpm, stock head will stop making power while my ported head will keep pulling hard until 7000rpm.

I trapped 105 mph with the stock head while I trapped 110 mph with the ported head, same short block, same turbo, same boost, same BMF intake manifold etc.

Green line is stock, blue like is how I had to match my ported head.
http://thelostartof.net/tryingbe/dodge/CSX/pumpeff.JPG

[thedon809]

I would hope a ported head flows more air lol. I was comparing intake to intake on a stock head. I feel a big difference. Now, if I stuck a ported head on there with a good cam to go along with the big intake, I'm sure it would really wake up.

[tryingbe]

People have cut open one piece intake manifold and discovered its poorly routed pathway and small neck, then re-weld it to make into a better intake manifold.

[Gaboon]

People have cut open one piece intake manifold and discovered its poorly routed pathway and small neck, then re-weld it to make into a better intake manifold.

I did a bunch back in the day, milled open, shelf removed, runners shortened to 6", inlet elbow replaced with a mandrel bent aluminum 2.5 id pipe and re-used the stock throttle body mounting flange that was opened to 2.5" id then was welded to the pipe.
I still run one on my car. With the cam I have in there, it will continue to pull over 7000 rpm

The 1 pc are terrible stock, that's on a modified engine. Stock engine you probably wouldn't notice much of a difference between a stock 1 pc and two piece.

[thedon809]

Bumped the boost up to about 12. Pulls pretty good even in 100°+ heat. I wanna crank this thing up but I don't feel like ventilating my block with a lightweight t1 rod yet.

[GLHNSLHT2]

How do you like having no AIS?

[thedon809]

How do you like having no AIS?Drives way better. No more hanging when shifting. Gotta play with it a little more. After a dead cold start it'll sorta hunt for 10 seconds or so then settle. The only thing I gotta figure out is a/c. I still have to drive it more but the idle does dip down when it's on. I'm a noob with mptune. About the only thing I know how to do is add fuel lol.

- - - Updated - - -

I did buy an adjustable iac replacement from modern performance that I want to put on.

[tryingbe]

The only thing I gotta figure out is a/c.



I have my a/c compressor wiring also wired a on/off solenoid to induce filtered air (vacuum leak) to the intake manifold to raise the idle speed by a few hundred RPM when a/c is turned on.

[chromguy]

Drives way better. No more hanging when shifting. Gotta play with it a little more. After a dead cold start it'll sorta hunt for 10 seconds or so then settle. The only thing I gotta figure out is a/c. I still have to drive it more but the idle does dip down when it's on. I'm a noob with mptune. About the only thing I know how to do is add fuel lol.

- - - Updated - - -

I did buy an adjustable iac replacement from modern performance that I want to put on.
What style AIS did you replace? I assume the pintle style.

[thedon809]

I have my a/c compressor wiring also wired a on/off solenoid to induce filtered air (vacuum leak) to the intake manifold to raise the idle speed by a few hundred RPM when a/c is turned on.That's brilliant. Don't think I would have ever thought of that. I'm assuming though the "vac leak" is there all the time the ac is on and not just idle, correct? Cause any issues doing it that way?

[thedon809]

What style AIS did you replace? I assume the pintle style.This car had a stock 2 piece setup. 87 Shelby lancer. It now has a Jeep 4.0 throttle body. The AIS that's on it is basically shut and unplugged. This is what I bought. https://www.modernperformance.com/product/mpx-iac-manual-adjuster-95-00-neon/95-99-neon-engine-throttle-body-and-intake-manifold

[chromguy]

This car had a stock 2 piece setup. 87 Shelby lancer. It now has a Jeep 4.0 throttle body. The AIS that's on it is basically shut and unplugged. This is what I bought. https://www.modernperformance.com/product/mpx-iac-manual-adjuster-95-00-neon/95-99-neon-engine-throttle-body-and-intake-manifold
Got it Pintle style on an LM just like my CSX.

[zin]

Sorry to speak out of turn, but I wouldn't expect it to have any real effect but for the desired higher idle/corrected idle when the A/C is on, the amount of leak would be swamped as soon as the throttle was cracked.

BTW, this reminded me that this is pretty much the same as the "pintle" style, they are both just a solenoid, the difference being that one is being pulsed (factory) and the other is just a fixed leak... Although, if one wanted to, and the capacity of the solenoid was big enough, one could pulse it just like the factory... That's assuming you want it to hold the RPM for you (personally, not a fan...).

Mike

[tryingbe]

That's brilliant. Don't think I would have ever thought of that. I'm assuming though the "vac leak" is there all the time the ac is on and not just idle, correct? Cause any issues doing it that way?

I'm using Microsquirt, and only have 1 output wire to work with so the stock 4 wire IAC was out of the question for me.
When warm, my car idles at 950 RPM with throttle plate close. I set the solenoid open when using a/c or coolant temp is below 140F which raise the RPM by 150 RPM or so.
I may play with the ford 2 wire PWN IAC to get a better idle control, but I'm in no hurry since it is 105F outside.


DIY sell a Jeep IAC adapter, just hook one end to your intake and the other one to filtered air.
https://www.diyautotune.com/product/custom-idle-air-control-body-for-use-with-jeep-4-0l-iac-valve/

[GLHNSLHT2]

never had an issue with no AIS and AC kicking on. Idle was set at 900rpms. Maybe because I reduced parastatic drag so much elsewhere that the car didn't care that the a/c was on or off.

[GLHNSLHT2]

Drives way better. No more hanging when shifting. Gotta play with it a little more. After a dead cold start it'll sorta hunt for 10 seconds or so then settle. The only thing I gotta figure out is a/c. I still have to drive it more but the idle does dip down when it's on. I'm a noob with mptune. About the only thing I know how to do is add fuel lol.

- - - Updated - - -

I did buy an adjustable iac replacement from modern performance that I want to put on.


There's a table for timing vs temp somewhere. I couldn't tell you exactly where as it's been 6 years since I've touched MPtune. It's a pretty flat curve, maybe 2 degrees of timing total added stock. If you bump that to 4-5 total under 100 degrees of engine temp you'll never know you needed an AIS. The extra timing will give you a cold idle of about 1100 that comes down to where the throttle stop screw is set by the time the engine see's 100 degrees of temp.

Like I said of face book I fill the passage way with gorilla glue ($4) break the pintle off the stock AIS motor and mount the stock AIS body back onto the TB and plug it in. No one knows it doesn't work :)

[GLHS60]

Lengel plenum + 1/2 spacer to a stock 2 piece lower that was crudely blended to gasket size while on the engine. 60mm Jeep throttle body. I can say, without a doubt in my mind that the head is NOT the cork.

My car has a t04e 50 trim with stage 2 turbine and .63 housing. It always had a pretty bad lag. Like your dragging an anchor. The classic, nothing is happening and then boom, 15psi and it's moving decently. Kind of like a switch.

With the new intake setup, the engine feels free. The power delivery is so much more linear and smooth. It feels like a modern turbocharged engine. I'm running like 8psi and it feels as fast as the old setup at 15psi. So far, zero downsides. Drivability is excellent. Even after eliminating the AIS.

Good info, appreciate you sharing!!

Thanks
Randy