The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support ExtremePSI
Please Support Morrison Fabrication

Which Intake Manifold 1g or 2g? [Merged 8-9]

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

96TalonAWD

20+ Year Contributor
225
0
May 3, 2002
Orlando, Florida
Yep thats my doubt which one is better? And what is the diameter of the 2g manifold in inches??


Thanks i dunno
 
Okay, I'm looking at purchasing a 1g throttle body, and a 1g intake manifold. I've read that it might cause complications with my 2g head. What are the risks, and do's/dont's to this procedure. Help me figure out if this is feesable and worthwhile.
 
Basically you will need to port out the 2g head to the size of the runners on the 1g intake manifold. It is not worth it. If you want the 1g intake manifold, you should just go with a 1g head.

The throttle body, however, could be a worthwhile mod. You would be upgrading from a 54mm throttle body to a 60mm throttle body. In order to hook it up, you will need to transfer your ISC and throttle position sensor over to the 1g, and then port out the inlet hole to your 2g manifold and throttle body elbow so it matches the 60mm throttle body.

Here is a link to aid you:

http://www.roadraceengineering.com/2gtbswap.htm
 
Just for comparison of how much you would have to port out of your 2g head for it to work:

Here is my ported & polished 1g head.

You must be logged in to view this image or video.


And here is a stock 2g head.

You must be logged in to view this image or video.
 
Thanks for the info but it wasn't actually what I was looking for. What would happen if I didn't port my head? if I just bolted up the intake manifold and throttle body. Why is this bad?

I've heard that porting your 2g head can cause too much airflow and be bad, and you should go with a 1g head. So my question is. Without a 1g head or porting my 2g head, what can go wrong? why is it bad?
 
Well you saw the difference in port size in the above pictures. Basically you would have a huge disruption in your intake when all the air that expanded to the 1g port size slams into a much smaller 2g port. It would create a lot of turbulence and you would probably even hurt your power output.
 
Thanks, thats the info I was looking for. How much money would a decent 1g head go for? How hard is would this project be?
 
mach v sells brand new 1g heads with no core charge, and you can get them ported if you want, their stage 1 is the stock head i believe, and it costs 900. but after going to their site i just realised that they have stage 1-6, and a stock head, the stock head costs 600, the stage 1 is ported a little. personally ill be going with the stage 5 or 6 once i get the money to do that, and also once my head becomes the thing that is limiting my power. (aka not the stock exaust with a fmic, smim, short route upper and lower intercooler piping, gm maf, the works on the intake side...)

used would probably run you about 200, but dont quote me on that one...
 
Okay, that seems a little expensive...I'm planning to finish my car with a 16g, 660's, a 190, safc2. if I just go with the throttle body and forget about the manifold and head, is it a decent mod?
 
yea but remember to port the 2g intake manifold where it meets up with the throttle body, no sence in going from a 52mm throttle body to a 60mm if the intake manifold is still 52mm where it meats....
 
tstkl said:
yea but remember to port the 2g intake manifold where it meets up with the throttle body, no sence in going from a 52mm throttle body to a 60mm if the intake manifold is still 52mm where it meats....
Porting of the 2g manifold to match a 1g 60mm TB is a necessity, not a choice. Same reason for 1g IM/2g head applies here.
 
For reference, I got my first used 1g turbo M/T head with all internals, intake manifold, TB, fuel rail, injectors, etc for $125 shipped. Then I brought it to my machine shop for a full rebuild for $200 for a total of about $250 (after I sold the coil back, fuel rail, and injectors off of it).

Something else that might help you find a good head for cheap, all 1g 2.0 motors have the same head, turbo or N/T. The only difference is in the cams, so you'll need a set of turbo cams.

For further aid, visit this link:

http://www.roadraceengineering.com/1g2gheadswaptechtip.htm
 
my friend just called me, and found a 1991 1g gst in a junk yard. He is pulling the TB for me, and, I wanna know if it's worth the time/trouble/money to do an intake/cylinder head swap from a 1g on a 2g??? I allways heard it makes good extra HP on a 2g.My car is not a daily driver, and I have future plans for a FMIC/HKS SSQ BOV/Turbo timer/boost controller, and many extras. Just wanna know if I should go over and give my buddy a hand with the head/intake pull or not. A quick reply would be appreciated!!!:thumb: thanks
Max
 
The head intake side is bigger on the 1g than the 2g, but bigger isn't neccessarily all you should concern yourself with. You also want the angle of the air to be more direct so that the air enters the chamber at a higher velocity, this aids in a larger explosion and therefore more HP. If you haven't figured out what i am gonna say yet, the 2g intake has a more direct angle into the chamber so really both heads have there advantages. Your best bet if you wanna spend the money would be to get the 1g head and get a 5 angle valve job done on it.
 
Im tempted gona go thru with the swap. Intake/head swap, but much later date. I'm gonna buy the parts, and get everything set up for the job. I would like to do more intensive research other than the above link for RRE.. I would like anyone who has done this swap to post here or pm me. I would like to know the pro's/cons for doing the swap. Thanks for everyones help.

Max:thumb:
 
I really liked the way my talon ran before it broke. A happy, awd, 10psi commuter car, not a street monster. Then the timing belt tensioner broke, bummer.

Now I have a newer, 4G61 head, which has ports just like a 2G head. I'd really rather not gasket match it to the 1G manifold, and I don't want to have to redo everything to put in a 2G manifold. The question, will the mismatched ports make the car run that badly? Anyone do this and not notice at all?

Also, where would one get new head bolt washers?
 
i just left it unhooked and it pulled a check engine light code but it didn't seem to effect the car but if any one has a way to make it so the check engine light off i would really like to know
 
Leaving it unhooked won't change the car at all except throw the check engine light. You get one cel for not having it plugged in and another for not having any vacum/boost source to it.

The way to hook it up with a 1g intake is to slightly trim the part that hooks up to the intake manifold and just hook up a vacum line to it.
 
are you talking about the MAP sensor? if you are what I did on my old 1Gina2G swap was to hook up a vac. line from the tip of the sensor (zip tied to ensure it wouldn't fall off the tip) then (the other side of the vac line) to one of the nipples on the Throttle body... no more CEL
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top