82firebird

I just pulled the 305 out of the 82 firebird I'm fixing up. I took the motor apart to find that it spun a bearing. Well, I have a 307 that came out of a 1968 Impala or Chevelle(not sure which). The 307 should drop right in there, right? I'm not going to go race anyone or anything like that, but I do want to have some repectable power, Would the 307 be the right motor for what I want? I've also thought about a GM crate 350, but with gas prices the way they are, I don't know. Any advice would help, thanks.

mrls199

I would go for the 307, i have always thought that these little engines were more deserving of credit than they got... they tend to run forever and can rev decent too. The only downside to them is their heads (1.72 X 1.50 valves and small ports) but they are easily pump gas compliant. If you swap to 305 heads I think you could easily have a potent performer with more top end than a 305

five7kid

iTrader: (14)

Depends upon how you go about this. The stock 307's were baseline, economy 2bbl carb engines, a mix of 327 and 283 dimensions. If you just put the complete engine in, you're going to be disappointed. After all, it costs just as much to build a 3-7/8" bore x 3.25" stroke 307 shortblock as it does a 4" bore x 3.25" 327, so they got cheap on the heads and induction (people think a smaller engine should cost less - marketing stuff).

However, with decent heads, exhaust & cam, and the induction from your 305, you can have a decent running powerplant. One issue you will face is the dipstick, which is on the driver's side. Headers will solve that, but you'll be taking care of that in the "decent exhaust" catagory, right? Good 64cc heads will let it breathe properly, cam doesn't have to be especially wild.

It's a plan with merit if you execute it properly. It will "drop right in there", but what else you bolt in with/on/in it will make all the difference. Whatever you do, don't settle for the stock exhaust - it chokes a stock 305!

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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R. 2.93 limited slip. Cat-back from '91 GTA, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LG4 w/'87 LB9 block, ZZ3 cam and intake, World 305 heads, Hooker headers & y-pipe, 3" Catco cat).
57 Bel Air, my 1st car. 0.030 over 396, Weiand Action+, Edelbrock 1901 Q-Jet, Jacobs Omnipack, 1-3/4" Hedders, TH400 w/TCI Sat Night Special conv & Trans-Scat shift kit, 3.08 8.2" 10-bolt w/Powertrax, AMSOIL syn lubes bumper-to-bumper. Best 15.1 @ 5800' Bandimere w/open diff & slipping tranny. Daily driver while Camaro was being put together.

82firebird

Thanks for the help guys. Anyone else want to comment?

83 z

I DONT KNOW MAN I HAD A 307 IN MY 72 NOVA 87000 ORIGINAL MILES AND IT WAS slow!!!! IVE HAD A FEW 305 THAT WERE FASTER BUT ITS YOUR CALL

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84 z28 b*itch red(i hate red) 350 700r4

MouseCamaro305

307.....hmmm well its probably one of the worst motors ever produced, 305's not too much better but a 2 bbl 307, talk about anemic, this things gonna be a lot slower than when you had the 305 in it, and when you mentioned the fact that youre looking into a crate 350, by all means!!!!!! l drove a caprice l know its a bigger car but still, it had a 307 in it and it was slower than turd, it was fall on it's face slow, no power whatsoever, might as well drop a 4 cylinder running on 1 cylinder slow. the difference in fuel consumption of a 307 2 bbl v.s. a 350 with a 4 will be difference but if its toned down it wont be that significant, go with a 350

five7kid

iTrader: (14)

Again, the performance problem with the original 307's were the heads and induction (and exhaust, and cam, and...). The performance problem with the 305 is the limitation of valve size and flow around the valves due to the small bore size. The 307 has less of this problem, because it gets its displacement with larger bore and smaller stroke than the 305.

With good heads, cam, induction, and exhaust, the 307 has more power potential than the 305. The economy comes from making the package efficient, and keeping an egg under your right foot - true for 305, 307, 327, 334, 350, 383, 400...

Speaking of economy, you can buy a lot of gas for the $2000 minimum the 350 crate is going to run you. What you have to decide is if you will be satisfied with the performance of a maxed out 305/307, vs about the same performance with a mild 350 that has room to grow.

IROCZ88

My '70 Nova had a 250 straight six in it and I could beat my friends '70 Chevelle 2bbl 307. That's pathetic.

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'88 IROC TPI 355, '69 truck 4-bolt, fully balanced, 9.75:1 compression, fully ported '70 truck heads(for now), Harland Sharp 1.6 Roller Rockers, Comp Cams CS 252AH-12, ported '86 TPI converted to speed density, Crane AFPR, Flowmaster 3in. exhaust, Edelbrock TES headers, all emissions equipment is still intact, plan on burning my own chips, many more mods and parts on the way as time and money permits =(
Best E.T. with TBI 305: 16.11 @ 82mph
Haven't been to track with new motor
If you have any questions on converting from TBI to TPI email me at jdkchevy70@yahoo.com
In memory of Dale Earnhardt, I'll miss cheering for that black #3 on raceday!!!

five7kid

iTrader: (14)

Come now, people, let's keep this between apples and apples, and oranges and oranges. The Chevelle could have had all sorts of problems, like needing a tune-up, in addition to other disadvantages such as extra weight and most likely a Powerglide tranny & highway gears. Put 5 people in each car, with a fresh tuneup in the 307, and repeat your "test".

On the other side of the spectrum, in 1974 I saw an econorail with a 307 run 9's.

The 307 was not, is not, and never will be a 327, 350, 383, 400, 434, etc. But, that doesn't mean it has no potential for better performance than what it had out of the factory.

slayer2000

iTrader: (1)

any engine is only as good as it's induction system. You could get a good set of heads cam and intake and headers would help wake this engine up. The main limit is the small bore size. While it's bigger the a 305 being under 4.00inch hurts breathing potential. Because of the bore you're limited to 2.00 valves or less so vortec heads might be a way to go. Ultimately the choice is yours but I would use the 307 until I could afford a good 350. just my opinion

nestz28

iTrader: (1)

Just my opinion, a 307 mod for mod will make more power than a 305, it has a larger bore/shorter stroke than the 305. I have a stock 307 in my nova with a TH350 and it is ALOT faster than my '84z with the 305/5speed with a fresh tuneup.

82firebird

Well, I've decided to go with the 307. I'm going to put a cam in it as well as an Edelbrock Performer intake manifold with a Quadrajet carb, how does that sound? Are there any other solutions to the dipstick problem, besides headers? How about one of those flexible dipsticks? Please help guys, thanks.


[This message has been edited by 82firebird (edited April 19, 2001).]

five7kid

iTrader: (14)

I've heard late-70's/early 80's Malibu's and El Camino's (?) or something w/SBC had the dipstick going directly to the pan on the passenger side. I've never seen it, though, so can't say for certain.

What's wrong with headers?