upper intake swaps

[Golgo13]

I have an 03 3400 with a cracked upper intake manifold, a friend just offered me a same style 3100 intake for free. My question, do they flow the same? I read somewhere the big port intakes do but i havnt been able to find the info again with the search feature.

second question, i just replaced the temp sensor in the lower intake, 3 wire, the dealer said the 03 had a two wire....so i picked up a 3 wire they said worked for my 96 gp. Any ideas? I thought all the new motors were 3 wire?


third, any way to decode motors and parts to determine year?

[bszopi]

1. Should be the same. There was a change somewhere in the years with a hump or groove inside the plenum to help flow direction, but I doubt you'd be able to tell a difference if you got one or the other.

2. 2003 should be a 3 wire.

3. Depends on the parts. Some lower intakes are distinguishable by a cast number (01,02, etc), but I have seen the 01 on a 2002 engine, so its not a definate. Otherwise, not really... most parts are shared across several years so they they don't increase cost by changing parts every year.

[Golgo13]

thank you for the quick response, im not looking forward to doing this today, dang rain but the upper shouldnt take long.

[bszopi]

Swapping the plenum should really only take 15 min or so. 6 bolts, a couple vacuum lines and the TB and you are done.

[onefastV6]

Where is your upper cracked at?

[SappySE107]

Yeah, thats what I wanna know.

They changed the design in 2000 and it gives more even flow distribution to the cylinder vs the 96-99 large port upper intake. The groove hurts the flow I think 5% average or more on the number 5 and 6 pistons compared to the rest.

[Golgo13]

it has a hairline crack around the 3rd cylinder runner (rear, middle), next to the intake bolt hole. I decided to jb weld it, it looked alot worse last night looking at it with a flashlight.


that and the intake my friend gave me looked horrible, needed cleaned inside and the outside had a gold tint to it, lol. I wasnt in the mood.