In the middle of a swap 305 vs. 350 QUANDRY! (1 Viewer)

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OK, I right in the middle of a engine swap for my 55 and I've discovered right before pulling the engine, the truck that I thought had a 350 actually has a 305. I didn't discover this until I got where I could read the casting numbers. According to the numbers it is a 87-91 Roller Cam One Piece Rear Seal Motor. I'm in the debate now as to whether to go ahead and put this motor in my 55 or look for a 350. This motor DOES run great with no issues but what about the power for a 55. Is it enough for a 55? IS ANYBODY RUNNING A 305 IN A 40 OR 55! I need some feedback as would apply to a 4x4 rather than the normal "305 is a dog and can't produce power" that you hear from the street guys. I'm building a "sometimes driven/hunting" type vehicle. Not a daily driver or serious wheeling truck. Quick opinions would be appreciated. I "could" buy a 350 crate motor but I really don't want to spend the cash and I do have this 305 in hand.
Opinions appreciated.
Thanks
 
Use the 305 and save your money

Unlike the street guys it doesent sound like your trying to get there and back. The stroke is the same between the two motors only the bore is smaller in the 305. Chevy full sized trucks use the 305 all the time without any complaints.

I happened to find and put a 350 into my FJ40 however, I was looking for a 305 because the economy should be slightly better. I've known a guy in town for years who first had his 305 in his FJ40 till it was written off, and then he swapped it into his FJ45 pickup. He made no complaints about power and wouldn't have put it in the heavier truck it it didn't have enough power.

The 305 will have more horsepower and torque than the FJ55 came with.

If you ever decide that the 305 isn't fast enough... you can swap in a 350 in an afternoon. Although, if your goals are as stated you'll never the extra .7 liters.

P.S. With the gearing that is in our trucks you'll never need the 350. I've towed both a 15 ton crane truck (GVW) and 5 ton Dump truck out of our yard after they got stuck in there.
 
i would rather run a 383 than a 305 you want low end grunt in the rocks
 
i would rather run a 383 than a 305 you want low end grunt in the rocks

Which also brings up a good question, What other drive train is being used? The 305 should be fine for the "sometimes driven/hunting rig"
 
I've got a 283 mounted to the stock drive train in my 40 and it works great.
 
The president of our local 4x4 club is running a 267 V8 in his FJ40... doesn't win races but it gets him there and back. Also, it's not on his list of things he wants to change.
 
305

What you guys are saying is sort of what I am thinking also. As stated, I don't have a need for much "grunt" on the rocks in that I'm not into rock crawling (We have Georgia red clay here) and with the stock 4-speed and gearing that he 55 has I feel that it should be fine on the power/torque end. I guess having always heard the 305 talked down upon kind of makes you wonder. Anyways as stated this 305 does run perfect, not a bit of smoke, idles nicely, and is "supposed" to have low mileage. It also showed real good oil pressure. I'm pulling it this afternoon and I'll go from there.

Any more experience or opinions appreciated, especially from someone with a 305 in a 55.

Thanks
 
No personal experiance, but I'd "think" the 305 shouldn't have the cooling issues a 350 would, if keeping stock radiator. Might want to look around ThirdGen.Org's mssg board, lots of 305's there with good info. Good luck, Al
 
I've used them all.
I got great power, and the best milage with a 305 I once used. I've gotten better off road torque with the 350's I've used, but at the expense of milage. The 305 got around 18 mpg while the 350's have only gotten maybe 14 mpg.
 
my .02

My previous engine was a carbed 350 that leaked like a sieve but had tons of power. When I switched over to TBI, I got a great deal on a non-running 92 305 G Van. I rebuilt the 305 and swapped in the TBI, and while it runs great, I miss the extra HP of the 350. Streetwise it is fine, but on those really big rocks or shelves that I am trying to crawl over it isn't enough. I will probably switch to a TBI 350 in the very near future. As for fuel economy, I didn't really see any benefits since I have my foot into it more than I had to with the 350. No real heat improvement either even after switching to an aluminum radiator. HTH.

Clint
 
My previous engine was a carbed 350 that leaked like a sieve but had tons of power. When I switched over to TBI, I got a great deal on a non-running 92 305 G Van. I rebuilt the 305 and swapped in the TBI, and while it runs great, I miss the extra HP of the 350. Streetwise it is fine, but on those really big rocks or shelves that I am trying to crawl over it isn't enough. I will probably switch to a TBI 350 in the very near future. As for fuel economy, I didn't really see any benefits since I have my foot into it more than I had to with the 350. No real heat improvement either even after switching to an aluminum radiator. HTH.

Clint
If you have a heating problem with a chevota, call or PM me. there are about a half dozen things you have to do right to cool a chevota, and most people screw up one or two of those things.
Jim
(562) 949-9494
 
My previous engine was a carbed 350 that leaked like a sieve but had tons of power. When I switched over to TBI, I got a great deal on a non-running 92 305 G Van. I rebuilt the 305 and swapped in the TBI, and while it runs great, I miss the extra HP of the 350. Streetwise it is fine, but on those really big rocks or shelves that I am trying to crawl over it isn't enough. I will probably switch to a TBI 350 in the very near future. As for fuel economy, I didn't really see any benefits since I have my foot into it more than I had to with the 350. No real heat improvement either even after switching to an aluminum radiator. HTH.

Clint

Out of curiosity, are you running 3.70 or 4.10 gears? That might be a consideration for a 305 over a 350, and may play a part with fuel economy. Also what tranny are you running? The 1st gear ratio can play a major factor too.

If you have a heating problem with a chevota, call or PM me. there are about a half dozen things you have to do right to cool a chevota, and most people screw up one or two of those things.
Jim
(562) 949-9494

It would be a benefit to many more people if you'd make a thread addressing these issues.
 
305

I will be running a stock 4-speed from a 1980 40 so the first gear ratio should be fine. I have a 73 FJ55 and as far as I know it should still have the stock 4:11 gears unless somebody has done some changing along the way. I haven't opened them up and counted teeth in other words.

Thanks
 
Out of curiosity, are you running 3.70 or 4.10 gears? That might be a consideration for a 305 over a 350, and may play a part with fuel economy. Also what tranny are you running? The 1st gear ratio can play a major factor too.

I have a 700R4 and split case behind it. I am running 4.10 gears with 37" MTRs. I have considered changing the gears, but would probably rather spend that money towards a 350 rather than polishing a turd :)

Clint
 
305

Well, the motor is pulled. I'm going to do a little cleaning up on it tomorrow and it looks like I'll need to replace the rear main seal while it's out also since I see a little oil leaking. I've decided to go ahead and put it in the 55 and see how I like it. As earlier stated, I can always replace it with a 350 if needed onece the whole SBC set-up is in place. I just can't see looking for a 350 right now since I have this good running engine in hand. Thanks for the info and opinions and I'll follow-up with some feedback later on the performance.
 
Well, the motor is pulled. I'm going to do a little cleaning up on it tomorrow and it looks like I'll need to replace the rear main seal while it's out also since I see a little oil leaking. I've decided to go ahead and put it in the 55 and see how I like it. As earlier stated, I can always replace it with a 350 if needed onece the whole SBC set-up is in place. I just can't see looking for a 350 right now since I have this good running engine in hand. Thanks for the info and opinions and I'll follow-up with some feedback later on the performance.

DOO IT! :cheers:
 
Sorry about the late post. If the 305 was working for you before and you thought it was a 350, stay with the 305. I agree with fyresq on the 4 speed. I have a 350 mated to a 4 speed with an Orion 4:1 transfer case. When I get on the gas it feels like the engine wants to jump right out of the cruiser:clap:. I am not sure if there is such a thing as "too much" horse power but there is such a thing as enough horse power.
 
305

I purchased this motor in a full size long bed chevy truck and it was plenty motor for that truck and actually if I hadn't looked at the casting # on it I would have never known the difference. At any rate the engine will go in my 55 and we'll see how things go. Thanks for the replies!
 

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