[Blitzkrieg]

Hey guys I'm new on here. I just bought a 99 intrepid with a blown engine. The car has less than 110 k on it. Good shape. The oil pan had been removed and it looks like a main cap and spun main bearing was found in the trunk. I havent got under it yet or looked at the engine. I did search your forums a little and found out a 3.5 can be swapped in. I am having trouble finding technical info though. Can anyone offer me some advice on common problems with the 2.7? Could it be that I could just replace the main bearings and it would fix it? I will look for other damage but would like to know usual fixes and problems. Also any cheap performance mods? Any good ones with stroke? Also how hard is it to swap for a 3.5? Will electronics work? Will tranny work? will suspension be strong enough? Any low cost performance to be added? Where can someone find tech data on this at? I have experience with engines to an extent, not a machinist or builder, but know how they work and can do most work if I have the tooling. I have been pretty deep into engines and trannys, just looking for more experienced advice before I start.
I did find some info today about 2.7's water pump issue. My car seems to fit the description. I still don't know exactly how much other damage may have been done elsewhere. Can the mains be replaced, and water pump and the engine flushed? I mean I will probably pull the pistons and have a look but I can't pull the heads without major work. What would you do? And what is this 3.5 HO engine? I can't find it yet for them years (99-2002). What would you do?

[paintballdude05]

Everything you need to know on the swap and more.

http://www.ebay.com/itm/Dodge-Intrep...item3364da9073

[SRT6INTREPID]

If it looks like a milk-shake in there and you have lower-end bearing job, get ready to yank the motor, it's junk now. You could fix it, but by the time you flush it, machine and rebuild the lower-end and redo your timing system and water pump, you'll have more into it than it's worth.

Seek out a 3.2 or 3.5 engine. Since you own a 99, you need a motor out of something from 98-01. You can get a 02-04 motor to work, but it requires many changes, including wiring, egr valve, cam gears and flywheel etc. Small things but headaches nonetheless. It's easier finding a 98-01 motor than a 02-04 anyways.

As far as getting the motor, you need the entire engine dropped. All accessories (power steering, alternator, a/c pump), and the engine wiring harness. You'll need small things like the throttle cable, rear air box, and power steering reservoir and hoses. Optional items would be things like the cruise control module, heater hoses, rad hoses, ac hoses...

Your transmission, and suspension is perfectly fine. In fact, you'll gain a nice performance bonus, as the only difference between a 2.7 and a 3.5 LH transmission is the final drive gears. It's a nice kick in the pants, and if you want a bigger one, consider looking for a set off of a Chrysler Prowler (uses the same engine and transmission).

Labor wise, two good afternoons and you can have one engine out, and the other in and running. Easy as pie to remove. Yank the wiring off the PCM, air box, exhaust v-clamps, unbolt the transmission and lift it out in the big portion of it. Drop the 3.5 in and reverse the process.... You'll need to shorten the passenger side exhaust down-stream pipe two inches. Additionally install the 3.5 P/S reservoir, which sits on the driver-side frame rail.

Consider doing small work to the motor before install. Timing belt, tensioner pulley, water pump and thermostat. You'll be happy you did it now versus when it's installed.

That sums up the most of it.

[Blitzkrieg]

The oil pan was already off when I got it, so I don't know how bad the oil looked. As far as the 3.5 , I can't really find where they were used between 98 and 02. Not saying they didn't but so far I've only seen listing for the 2.7 and 3.2. I will look, if I have to change the engine I want it to be higher performance. That 2.7 sounds like a great design if only they had thought more about the water pump and crank case ventilation. If I find a 3.5 I would like to do a little extra with it also, are there any cheap things I can do to add some power? Maby a home made cold air intake or something? Perhaps even a dynomax super turbo muffler?

[Blitzkrieg]

I don't understand what you mean when you say machine work. I understand replacing the water pump. I have been looking for a 3.5, with no luck so far. And paintball dude, I may be interested in your manual, but from what I am reading what advantages can you offer from what other posters are saying about it being a direct swap? I'm trying to stay low cost here as well, though I will spend a little more for better stuff depending on cost vs. reward. I am about to get my garage area ready to put the car in and dig deeper in the engine. The windage tray is still on so maby it will hold a story. Was the 3.5 offered in 300 M's or what? Would a prowler have the 3.5? Is the 99-01 3.5 better than the previous one? I look at specs and see that the previous 3.5 really wasn't all that, though it was better on power. The power didn't come on as quick and broad as the 2.7 or 3.2. In fact the 3.2 had the same or more right? I will look again to be sure. Thanks guys

[Crash Override]

It's not actually paintball's manual, it's daytrepper's, he's put together a step by step manual on how to convert a 2.7 to a 3.2/3.5 including any or all anciliaries that need to be changed, part numbers for Dodge to get the needed parts if they didn't come with the engine, it's a full conversion manual all in one place.

Mechanically the engine will fit straight in, but some of the 2.7's control cables (cruise control cable, throttle cable etc) won't swap to the 3.2, hence the howto.

[SRT6INTREPID]

98-01 - This is the first "production run" of the second gen LH cars, the 2.7 and 3.2 were dominate. That said, I've seen some early year LH vehicles with the 3.5, mostly 300M's and LHS's. Everything else was offered with 3.2's if they were high-trim models.

02-04 - This is the second "production run" of the second gen LH cars, the 2.7 and 3.5 were dominate. The 3.2 was discontinued. The 3.5 was reserved for "higher-end" models, like the ES, SXT, RT Intrepids and 300M's and LHS's. I've actually never seen a Concorde with a 3.5.

The Plymouth/Chrysler Prowler was only offered with a 3.5. Even though the engine and transmission are the same out of the LH vehicles (difference being they used a drive shaft system between the engine and tranny), the likely hood of finding a wrecked or parted out Prowler would be RARE, and I mean RARE.

Daytrepper's manual is definitely worth purchase if you have any question or doubt about the process. He went to extreme depth to make sure everything is covered. A friend of mine had a copy of it and I peaked through it, I'd consider it the LH engine swap bible.

When talking 2.7, it's an interesting topic. The motor is incredibly strong, reliable and well engineered, with the obvious exception. If they had designed the water pump so it was not able to leak directly into the main oil sump of the engine due to gasket or bearing failure, it would literally not been an issue-motor.

The issue with the 2.7 when it's water pump fails is a pretty signification chain reaction. If the engine was run, driven or left with the contents of the cooling system in the oil, you can be sure enough that any bearings which have come in contact with the mixture are damaged. The coolant washes them out. Additionally the timing system relies on oil-pressure, and the oil pressure would have been significantly reduced, running the risk of timing skipping chain leaks, or worse, causing the pistons and valves to crash. The common "engine sludge" complaints are the source of the water pump leaking and frankly are only the tip of the spear.

If you want to make your Intrepid into a bit of a performer, you certainly can - just don't expect to make it into a Lamborghini. In a nut shell, once you throw that 3.5 motor into your car with your original 2.7 transmission, the difference in final drive gears will give you a great kick-in-the-pants low end torque difference (keep in mind, you can change these gears at any time through a service panel). You can buy and make your own cold-air intake system, K&N offers ones. There are lots of exhaust systems offered as well. Aluminum underdrive pulleys also exist. Many small goodies that can make a difference.

If you really wanted to throw money at it, again this isn't a cheap venture, you could consider adding a single or twin turbo setup, or centrifuge supercharger. Again, requires lots of custom fabrication and can be costly, you'll also need to beef up the transmission too (Kevlar clutch pack).

There is also the stroker route. Many people are yanking their 3.5's, and throwing in the 4.0's crank and pistons and with the right know-how you have a 4.0 Stroker.


For now. Find a motor, and the accessories and go from there once you know how much you can throw at it.

[Blitzkrieg]

My gf has an 05 grand prix. It is a good car but she doesn't like it anymore. I would consider building this intrepid up for her, probably with a 3.5. A turbo would be cool or supercharger, but probably to expensive. I may look into the cold air intake. Thanks for the info on the 2.7. I don't understand the part about the timing being run by oil pressure though. The 2.7 would be a great engine to put a turbo on. I will probably buy a manual for the car regardless, so I have to choose between chiltons or haynes. Is there another option? I know when I had a camaro the manuals were conflicting and I found a place called proppsys or something like that , that had more acurate info. A shop manual costs a lot. This car has 100k on it and is in good shape. I would have it painted as well if I keep it. Maby make a vintage dodge look. The racing green, with blue, or orange or purple. I found a guy that does low cost paint work. The 3.5 sounds most attractive right now.
And paintballdude , I have a tipman A5 and am looking for people that play still. I put the response full auto trigger on mine. great gun but the model 98 shot straighter.

[SRT6INTREPID]

The tensioner on the chain runs by oil pressure.

No oil pressure, chains slacks, skips time just enough to jump one or many teeth. Valves ahoy!

You can download the Factory Service Manual here for free in PDF format. Has EVERYTHING, you will ever need to know how too do.

My Intrepid is currently being painted right now, went with the Orange used on the Daytona Ram Trucks, which I guess is also used on the Vipers as well.

On the LX platform (Charger, Challenger, Magnum 300C) the boys are putting centrifuge superchargers on the 3.5's. They work some snappy so I've seen and read. But the transmission there is a little more robust than our 42LE's, hence why I mentioned a Kevlar Clutch pack for your tranny. Either way your looking at a $3K-$5K venture there. Definitely a labor of love, not a Wal-mart bolt-on.

[Blitzkrieg]

hey thanks. I will go check out the local pull a part and a few junkyards around for a 3.5 in a 300M or LHS or anything wrecked. I definitely want a 3.5 over a 3.2. The 30 hp more is worth it. A used engine company sells them for around 1500. Funny that the prowler engine is cheaper than the 300 engine even though it is the same. Even has the same vin id of G. I will find one soon and buy that manual from daytrepper.

[SRT6INTREPID]

I'm curious what changes would have to be made to make the Prowler motor work in our cars. I assume they have an EGR valve and same cam gears as any 3.5 from 99-01. I'm assuming you'd only need to swap possibly the engine harness and flywheel?

[Blitzkrieg]

I was under the impression it is the same engine. Someone did say that I think. Maby I missunderstood. Probably different brackets but flywheel should be the same. Am I missing something? Is it a better engine? Also what would have to happen to put a V8 in one of them cars? Is there a transaxle that would bolt to one? I would love to put a 5.7 or 5.9 in one. Just don't see it happening due to wiring, fuel pump, computer, tranny, tranny computer and probably a long list of things that the do it yourselfer can't afford.

[Blitzkrieg]

I found a 2002 , 3.5 engine for 650 local so far, but you say the 02 will not swap directly? I just bought daytreppers manual. I like to see small businesses do well. This guy is a good example for the rest of us. Now to find that shop manual on here.

[SRT6INTREPID]

The Prowler motor is identical - the PCM just has a way more aggressive tune. But like 98-01 and 02-04 in our LH's the 3.5 has some variations, so one can only expect there to be small changes. Just a matter of swapping the odd piece.

Look at the 3.5 in the new LX cars. Same engine, but they altered the accessory layout so the timing belt housing is different, and valve covers marginally to accept the new coil packs. If you have both LH and LX platform engines in front of you, you can make either work in both platforms.

Lot's of people have thrown V8's into Intrepid's and Prowler's. It's an ambitious project, and you're likely to not get everything 100% without a lot of time, resources or just plain money.


No, a 02-04 motor will not "directly" swap with a 98-01 vehicle and vice versa. Refer to daytreppers manual, or this thread:
http://www.dodgeintrepid.net/showthread.php?t=76738

You can find the Factory Services Manual here:
http://www.dodgeintrepid.net/showthread.php?t=94402

[Blitzkrieg]

Hey I have a 99, does anyone have a manual for a 99? I understand there are some differances from the 98-01 and 02-04.