2.5L to Chevy 350 conversion question

Quik8slvr

New member
1040859

First off, i know this has been covered somewhat in previous posts, and i've already been in touch with Advanced Adapters a little but they take so long to respond i thought i'd ask in here for a little more specific help. basically i have a 91 YJ with a 5 speed and whats about to become a bad engine, its really leaky on oil (about a quart a week, and its leaking it not burning it) and i think my compression is off, or something, because up till about 3 weeks ago, when the bad oil leak kicked in, i could easily do 65-70 in 5th gear on the highway, now as soon as i put it in 5th gear i lose all pick up whatsoever, and god forbid i have to go up a hill even a small one cause with out dropping back into 4th i will slow down to about 50 mph...so all said and done its put me over the edge for dropping a Chevy 350 in.



Here's my questions:

1. How many total hours of work involved? I'll either be doing the work with my friends dad or a guy from my local Jeep club the Eastern Shore Jeep Assosiation

2. Aside from strictly the Engine/transmission, how much of a total bill am i looking to run? i mean everything together from Radiator, to altinator, starter, ect ect....dont worry about adding it all up if you dont know, but if you've done a similar Conversion im interested in knowing all together how much it cost



Im on a Limited budget, about 5,000-6,000 is this going to be enough? I need absolutely every part required, i have nothing, i know a big part of the question is how much i'd have to spend on the engine and transmission but i've been searching around trying to find prices so if anybody has an opinion on where to look and who to call about it i'd apriciate that aswell...But any help you can give me on even giving me a general ballpark on what it would cost, or how much it cost you to do it if you've done it would be apriciated.



Thanks Everyone,

Josh Quik8slvr@hotmail.com[addsig]
 

1040861

in my opinion, 5-6k will be more than enough. We've done several conversions at the shop I work at, and it usually runs the customer about 4,500 or so (depending on the motor they want -- ie: 350 TPI or TBI or carbed.) It takes us about 3 days to do including the welding in of motor mounts. That's using air tools of course too.THe convert I'm looking into will run me about 3,000, but I already have a 350 TPI out of a 98 Z28.

Advance Adapters has a lot of good info in their catalog also. It's worth getting. (Again, my opinion.)
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1040872

wow, 3 days? i've been thinking more along the lines of a week or 2, where exactly is your shop? nowhere near Maryland huh?



Im looking for engine/transmission combos right now, is getting it from a Camaro ok? or do i need to get it out of a truck? i thought something had to do with needing a 4wd transmission? How much more should i expect to pay for a Fuel injected engine as compared to a carburated engine? any ideas on where to find such an engine?[addsig]
 
1040873

Found an engine and a transmission, now just need to know if it will fit in my jeep, the engine is a Chevy 305 (carburated) with an automatic transmission (not sure what transmission) out of a Chevy Impala, the engine runs strong and has about 88K mi on it, i can have the whole car for $350 and all the neccesary engine parts, my question is, how much would it run me to do a rebuild on the engine, which i want to do regardless while i have it torn apart, and how much to do a rebuild on the transmission, if it needs it....thanks for the help[addsig]
 

1040876

$350?? not bad at all. We have a guy that rebuilds our transmission's for us for about 350-400 our cost (to the customer or retail probably about 5-600). If it out of an 88, it's probably a 700R4 or maybe a turbo 350, but probably the first one. Rebuilds on small block Chevys are pretty cheap these days. Anywhere from 300-1500 depending what you want in it (hi-po parts and such) and how much work needs to be done (like decking the block and heads, boring the cylinders and port and polishing). Make sure to get the proper tail shaft assembly for the transmission to fit your transfer case. ANd get rid of as much of the computer junk as you can. You might have to go to painless wiring to get new hook ups for your gauges and stuff, I'm not sure. GOOD LUCK!!!
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1040886

Took a look at the engine, it didnt start up real well but it had been sitting for a few months, after it started it ran strong, i didnt notice any oil leak under the car but it did have some smoke coming from the exhaust. would that be corrected with a rebuild? the transmission was the th700R4, however my local jeep expert, who's done a v8 conversion, but not with a 700R4 said he belived the transmission was too long, and said that i needed to find a 4wd transmission, either a 4L60E or TH350/400 out of a 4wd truck. I found a rebuilt 4L60E online for a very reasonable price, and now my question would be is it worth $350 for the engine, alt, starter, wiring harness? considering it would need to be rebuilt, or would it be better to go with something newer like a 350 from jasper engines for about $1700? If i spent about $2500 on engine / transmission would i be able to cover the neccesary parts and labor and still stay under $6,000?[addsig]
 
1040887

If it smoked at start up and then went away, I'd say it was just vavle seals, but if it was all the time, it sounds like rings. All in all it's still worth the $350. your Jeep guy is correct, you would need a 4x4 transmission. The 700r4's from cars are a tad to long, and I'm sure if anyone makes adapters for them. If you go with a Jasper motor (which are good motors), just remember that it will not be a complete, drop in, ready to go motor. There would be parts you would still need to get --- sensors, sending units, possibly intake and carb, valve covers and stuff. You might want to call them and see if they have "drop-ins" available. For me, the warranty would be something to consider to. Even if it cost you 2,500, you should still be able to come in under your 5-6k mark. I snuck i peek at one guys bill we just finished and it was 5,770 for a 350 TPI and 4L60E transmission. That was with us buying the parts to. Of course those were used and NOT rebuilt.[addsig]
 

1040893

I was talking to a mechanic that i work with and he told me i should stay away from the 305 he said all in all they just werent great motors and they notoriously burn oil. He did say that all of the accesories, alternator, starter, mounting brackets for them, fuel pump and things like that would be compatable for the 350 motors, and most of those are readily available from most salvage yards, i also found a 350 motor (complete) from out of a Blazer for $450 ( no transmission ) with 95K on it. In your opinion do you think it would be better to go used and rebuild myself or go with a remanufactured from Jasper and have a waranty? Also any idea why a reman. 2.5L 4 cyl engine from jasper is like $2,300 and a reman 350 is $1,662???? thats like more then double the engine...dunno makes no sense to me. My other question that i came across today was about the exhaust, i was looking at my 4wdhardware magazine and saw that they only offered In-Frame headers for the Chevy - YJ conversions, is there a company that makes fenderwell headers? i've seen them on jeeps, and i really like the way they look and how they come out infront of the wheels, any ideas?[addsig]
 
1040902

Onr thing with Jasper..... core charge.... if you don't return the same engine you bought, you will be charged a core charge up to around 500 or so, unless arrangements have been made with them to accept your motor. As far as the 305 thing..... the only difference between a 305 and a 350 is the bore and stroke (I think that's right), otherwise, it's the same block and heads. Personally, I prefer the reman, warranty, warranty, warranty. Do it yourself and you get no warranty, mainly headaches. LoL. Exhaust.... let's see..... we usually use rear dump manifolds (like the old vette style) which are readily available from most parts houses. Then, we send them out to an exhaust shop (shhhhh... Midas) to finish it off from the manifolds back (with cat converters depending on where you are). I haven't seen a decent set of aftermarket headers yet. If you find some.... let me know. The reason for the price difference in the 2.5 and the 350 is simple... there's more 350's out there than 2.5's. Simple supply and demand. [addsig]
 
1040907

yeah, i emailed jasper about accepting my engine for the core, i figure they can Reman mine and make more money off of it so maybe they'll accept it, if they dont i dont know what im going to do, i havent found anywhere that sells reman engines with waranty's that dont want a huge core deposit for same engine returned, except Jegs but all their engines are High performance and i dont need to pay for all that....The headers for the conversion are in the 4 wheel drive hardware magazine, they're made by like Hed or something like that i dont remember, but they dont make a Fender well header for the YJ, only inframe, which requires custom dual exhaust, whereas the fenderwell's i wouldnt have to get custom made, i guess i'll just end up having to get it custom, i dont think im going to get Cat's, just flow master mufflers, i dont want it to be too loud, just nice and deep, and in Maryland you have to get an inspection when you change owners, so for aslong as i own the car i never have to get another inspection[addsig]
 
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