Author Topic: Worth swapping from 4.65 to 4.90 with 33"'s?  (Read 11558 times)

Shovel

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #15 on: February 05, 2018, 09:24:24 AM »
There was a member on the Facebook that used the diamanté intake and he claimed he felt nothing different other than louder intake noise. Shovel go to the facebook page and type in "Josh Moe" and it should pop up.

Thanks for this tip! 

I found his thread - maybe it's an apples-oranges thing he's using the regular Diamante manifold which I don't think has much of an advantage over ours.   
I think the plastic manifold on 04+ Endeavors stands a better chance of delivering flow & velocity - but it might also not be a very easy swap due to how it interfaces with the lower manifold. 


kalieracer

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #16 on: February 05, 2018, 06:16:10 PM »
The endeavor plastic manifold is not going to work. There will also be an issue with the tb / kick down cables and throttle cable .  I have been thinking about this for months given I am finishing my 3.8 swap and looking to max power. I have come up against a wall with stock parts or parts off other mitsu / Korean cars. In the end I will get a custom manifold either printed or made . Charger X3 came up with a way to mate a 3.5 DOHC manifold to 3.8 to make decent power. On a gen 2.5 this is not for the faint of hear and will require a mix of parts. Not worth it for 6G74 Sohc.

There is also an issues the lower plenum in later cars in that they changed the angle of the fuel rail mounts because it was setup for return-less fuel setup.  As for improving the intake and exhaust, headers and exhaust will go a long way. Intake I was thinking of creating a new airbox that would allow my snorkel to create a ram air effect and using hard pipe that was polymer to reduce the charge temp and pholinic spacers.

Quote
In this message,  Kalieracer had offered that there might be some power to be gained by improving intake and exhaust.    I was a fool and clicked the wrong thing and ruined his response.. - Shovel 

If I were to do any intake modifications on the 3.5SOHC I think the most promising path there would be to try to adapt an endeavor plastic intake manifold to our engine.    Velocity plays a huge role in making power and that intake clearly is built for charge velocity - plus it's sure to keep the intake charge cooler & it weighs a few pounds less.      I don't think anybody's done that swap yet - I just need to get the parts together so I can be that guy if nobody else beats me to it. 

On the exhaust side I'm pretty confident there's a little power to be had,  probably above the butt-o-meter threshold even.     My money's on going  2.5" from the catalytic back,  with either a straight through type muffler or at least a "turbo" type.     I'm not convinced that chambered or delta mufflers actually flow better I think they might just be louder.

Shovel

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #17 on: February 05, 2018, 06:52:02 PM »
The endeavor plastic manifold is not going to work. it will put the tb in to the firewall.  I have been thinking about this for months given I am finishing my 3.8 swap and looking to max power. I have come up against a wall with stock parts or parts off other mitsu / Korean cars. In the end I will get a custom manifold either printed or made . 


Ouch, I had its orientation backward in my head, I thought it would put the TB out the other way.      What about those RPW intakes?    I mean, other than being more than $1k..   sure looks like they're built with care.   http://www.shop.rpw.com.au/online-store/products-by-vehicle-manufacturer-2/mitsubishi/mitsubishi-magna/mitsubishi-magna-1996-07/air-intake-systems-24/intake-manifold-6g72-74-detail.html


kalieracer

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #18 on: February 05, 2018, 07:03:30 PM »
whole set of other issues. They are good for up to 30+HP and 30tq on NA Magma 380.. Fitment is an issue on the Pajero / Montero. If you want to PM me we can discuss options. You are welcome to come mess with the mivec montero with I bring it to Ernest shortly and it will then be going to AMM fab in AZ for a custom intake manifold

The endeavor plastic manifold is not going to work. it will put the tb in to the firewall.  I have been thinking about this for months given I am finishing my 3.8 swap and looking to max power. I have come up against a wall with stock parts or parts off other mitsu / Korean cars. In the end I will get a custom manifold either printed or made . 


Ouch, I had its orientation backward in my head, I thought it would put the TB out the other way.      What about those RPW intakes?    I mean, other than being more than $1k..   sure looks like they're built with care.   http://www.shop.rpw.com.au/online-store/products-by-vehicle-manufacturer-2/mitsubishi/mitsubishi-magna/mitsubishi-magna-1996-07/air-intake-systems-24/intake-manifold-6g72-74-detail.html

kalieracer

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #19 on: February 05, 2018, 07:10:19 PM »
For high altitude.. I would use the computer we are working on for the mivec swaps and run E85. It also adds knock control and tuning + wideband support, electric fan control. Get rid of the fan clutch and get 5-10hp

jaccox

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #20 on: February 06, 2018, 07:51:49 AM »
Ouch, I had its orientation backward in my head, I thought it would put the TB out the other way.      What about those RPW intakes?    I mean, other than being more than $1k..   sure looks like they're built with care.   http://www.shop.rpw.com.au/online-store/products-by-vehicle-manufacturer-2/mitsubishi/mitsubishi-magna/mitsubishi-magna-1996-07/air-intake-systems-24/intake-manifold-6g72-74-detail.html
[/quote]
Clicked on that RPW intake and it looks nearly identical to what I assume the plastic diamanté intake looks like (someday i'll find some random Mitsubishi's at the junkyard and have some fun...). But i'm sure it flows a lot better than the plastic one.
1999 Montero. 33x10.5x15 General X3's. 4.90's w/rear locker. Full armor. ADD idler arm. ADD 1.5" complete lift. Siberiean Bushings everywhere. 150W alternator with upgraded 4 AWG leads and grounds. 2nd Battery in the rear for camping stuffs to come.

kalieracer

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #21 on: February 06, 2018, 09:05:55 AM »
Diamante is a metal manifold. Plastic is the endeavor. The RPW manifold creates a bit smoother flow and uses velocity stacks on the runners to increase the speed of air being forced in to the motor. Based on the photos the plenum is larger in volume so it holds more air than the stock Magna380 unit.

On the 3.5 SOHC motor I don't think the just swapping the intake manifold will little difference. Using a K&N filter and getting some bolt on's like headers and exhaust will help make the most out of the stock motor. Sure you can coat the intake and plenum with ceramic paint or install a phenolic spacers to cool the air charge. A tune will help too.  I was discussing the truck with my friend Mike at RRE. He mentioned when they had a customer with Pike's Peak prepped EVO the customer had (Merlin) fly out from AU to do the final tune at altitude to get the car to run 100% in the thin air. Gearing will maximize the available power, but adding a bit more power might just fix the issue as the 4.63 gear is a good spec for truck that does lots of road driving. I am looking to take my truck from 4.27 to 4.63 and just add the 40% reduction gear for the low range for off roading. I want decent milage on the road for overlanding.

In the case of my truck I have fairly fresh 3.8 Mivec motor, engine management, headers and exhaust. My truck is meant to run on 91 pump. My issue is how to make the most power and low end that is usable for the truck. The motor 4G eclipse can make 300+ HP and TQ to the wheels with just intake / exhaust and headers using their stock intake manifold that is also sorta shitty design.

 You have several things going on with the truck and motor.

1. The motor is tuned for max life from the factory, so it's very conservative in terms of timing and fuel (runs a bit rich) and meant to run on pump 87 and in all conditions fairly well and safely (heat / altitude / cold / below sea level)
2. The EMC does not have knock control so they leave a big margin for safety.
3. Exhaust system / Exhaust Manifolds are fairly restrictive.
4. the current intake manifold is made for low end, it has long track with small runners to increase velocity and tuned to keep that curve low.
5. Most of these motors are not factory fresh and are a bit tired these days so they prob make 15% less power then fresh rebuild.

Ouch, I had its orientation backward in my head, I thought it would put the TB out the other way.      What about those RPW intakes?    I mean, other than being more than $1k..   sure looks like they're built with care.   http://www.shop.rpw.com.au/online-store/products-by-vehicle-manufacturer-2/mitsubishi/mitsubishi-magna/mitsubishi-magna-1996-07/air-intake-systems-24/intake-manifold-6g72-74-detail.html
Clicked on that RPW intake and it looks nearly identical to what I assume the plastic diamanté intake looks like (someday i'll find some random Mitsubishi's at the junkyard and have some fun...). But i'm sure it flows a lot better than the plastic one.
[/quote]

Cosmos99

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #22 on: February 09, 2018, 08:55:22 AM »
Quote
In this message,  Kalieracer had offered that there might be some power to be gained by improving intake and exhaust.    I was a fool and clicked the wrong thing and ruined his response.. - Shovel 

If I were to do any intake modifications on the 3.5SOHC I think the most promising path there would be to try to adapt an endeavor plastic intake manifold to our engine.    Velocity plays a huge role in making power and that intake clearly is built for charge velocity - plus it's sure to keep the intake charge cooler & it weighs a few pounds less.      I don't think anybody's done that swap yet - I just need to get the parts together so I can be that guy if nobody else beats me to it. 

I am going to a custom 2.5" exhaust in a few weeks. I would be interested in the intake manifold swap too if it adds power.

On the exhaust side I'm pretty confident there's a little power to be had,  probably above the butt-o-meter threshold even.     My money's on going  2.5" from the catalytic back,  with either a straight through type muffler or at least a "turbo" type.     I'm not convinced that chambered or delta mufflers actually flow better I think they might just be louder.
Gen 1 1987 Radier 2.6 ( sold )
94 Montero LS with 93k miles
99 Montero overland ready.

Cosmos99

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #23 on: February 09, 2018, 08:58:19 AM »
For high altitude.. I would use the computer we are working on for the mivec swaps and run E85. It also adds knock control and tuning + wideband support, electric fan control. Get rid of the fan clutch and get 5-10hp

I am eagerly waiting for the 3.8 swap solution. That will be the best way to go.

Gen 1 1987 Radier 2.6 ( sold )
94 Montero LS with 93k miles
99 Montero overland ready.

kalieracer

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #24 on: February 09, 2018, 12:21:54 PM »
The swaps are worked out, you can do 3.8 (non mivec) without changing the ecu, that motor with headers and exhaust is good for 245-55hp. The mivec is all worked out too, we are just working on cost effective ECM. I am exploring alternate intake manifold options as I want to get the max power out of the truck.


For high altitude.. I would use the computer we are working on for the mivec swaps and run E85. It also adds knock control and tuning + wideband support, electric fan control. Get rid of the fan clutch and get 5-10hp

I am eagerly waiting for the 3.8 swap solution. That will be the best way to go.

DR1665

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #25 on: February 11, 2018, 01:14:35 PM »
AMM fab in AZ for a custom intake manifold

Whoa. Mine still in the business, then. That's good to hear. Your should ask him about ITBs while you're at it. Haha.

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kalieracer

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #26 on: February 14, 2018, 11:19:56 PM »
Yeah.. his work is top notch from what I see on the interwebz.. Since my truck is going to Ernest for regear / front locker, Mike's shop is 40 mins or so from there, figured I would have him help get the most power out of the truck.

AMM fab in AZ for a custom intake manifold

Whoa. Mine still in the business, then. That's good to hear. Your should ask him about ITBs while you're at it. Haha.

(Old school connections.)

BottomFeeder

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #27 on: February 24, 2018, 11:29:29 PM »
How does the altitude affect gearing?  I thought the ECU would compensate for altitude by riching or leaning the fuel mixture depending on high or low altitude?  I had only had issues when I had a carb at higher altitudes.  I went to altitude in my 95 SR and had no problems at all.

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kalieracer

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #28 on: February 25, 2018, 02:16:35 AM »
The altitude does not affect gearing. On NA cars the power loss is more pronounced as they have no means of cramming more oxygen in the mix. Based on previous posts he has larger tires and gearing matched to smaller tire. That being said he was running 4% loss in tq based on gearing. So now add a 58.6 HP loss in overall power at 10000ft of elevation and his truck feels like mule that is about to die. I know when people go to run Pikes peak they retune the cars / trucks at altitude to make them run the best they can.

the mathematical equation for power reduction due to elevation oxygen restriction is:
hp loss = (elevation x 0.03 x hp @ sea level )/1000

How does the altitude affect gearing?  I thought the ECU would compensate for altitude by riching or leaning the fuel mixture depending on high or low altitude?  I had only had issues when I had a carb at higher altitudes.  I went to altitude in my 95 SR and had no problems at all.



Se7en62

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Re: Worth swapping from 4.65 to 4.90 with 33"'s?
« Reply #29 on: March 19, 2018, 01:47:05 PM »
I'm also running 33's on a Gen 2.5 Winter, but with stock 4.27's. We plan to relocate to CO, but in the meantime we do annual trips up to explore the backcountry. I'm planning on going with 4.63's when I upgrade my gears mostly due to the cost of 4.90's for those of us with factory air lockers.
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