[Bad_Company_307]

Hellow fellow hot rodders. I am really new to this awesome site, and I am trying to obtain any information possible on the Chevy 307.

I have a nack for rat rods and s10 lowryders. My current project is a 88s10 that I have lowered as low as low can go

I won a 307 on a friendly bet. I have since done the following to the engine :

Installed a Edlebrock 4barrel 600cfm
Installed a Edlebrock Performer Air-Gap 250 Intake
Installed a MSD and Blaster2 Coil
Installed a pair of Hooker Headers

I am awaiting my new heads for her. Once I get the heads I am completely overhauling the entire engine. I am going with hydrollic rollers, a Lunati Cam, and getting the entire block dunked and cleaned. Then I will reassmble.

I am using 4.11 posi-gears. I have replaced all chassis and suspension parts that needed or I felt I wanted to performance upgrade. I am using crager rims that are rapped in Pirelli's. Everything has been shaved on the body and is completely ready for paint. Which waits on me, and my engine upgrades.

I am building this motor up for several reasons. First, to gain the respect back of the 307. I cant tell you how many people I have meet that just straight poop on the 307 without owning one or giving one a whirl. Most just say I owned one and it died ( thats the users fault typically, not the motor).
Secondly. Waaayyy to many people go with a 350. The 307 is a decent motor than can pull some great numbers. Especially in a light truck or car, these motors are a screamer if you build it right So I am buidling to be slightly different.

So, I should have some pics up by tomorrow morning of the current progess.
The body doesnt look that great at the moment because she is all ready for paint, minus what I need to strip out of the cab. I may just make a video and post a link to youtube so you can view and enjoy a 307 I sincerely welcome anyone with any 307 exp. or with any good information pertaining to the 307. I am always up for learning about this motor.

[Dirty Biker]

awesome man! Sounds great! I like 307 motors too! People dont like them I think because the cylinders are a tiny bit smalller and that limits the valve size a little bit. You didnt say what heads you were using but you could always put some vortec heads from a 305 on there tho, that might help get some extra power and mpg out of it. Or, make it into a 327 by boring it out .120 to 4 inches and using 327 pistons in it, or using the 307 crank in an old 350 block and the 327 pistons. Then you could use big valve heads. Ide say just stick some 305 vortec heads and on there and your cam and some fresh rings and see how that works. Maybe somebody else will chime in tho..

[ericnova72]

You can't bore the 307 block .120" oversize, you will hit water or the bore walls will be so thin it will be practically useless anyway if you don't see water.

Probably not a bad place to try the L30 305 Vortec head, I'll agree with that.

[Bad_Company_307]

Originally Posted by Dirty Biker

awesome man! Sounds great! I like 307 motors too! People dont like them I think because the cylinders are a tiny bit smalller and that limits the valve size a little bit. You didnt say what heads you were using but you could always put some vortec heads from a 305 on there tho, that might help get some extra power and mpg out of it. Or, make it into a 327 by boring it out .120 to 4 inches and using 327 pistons in it, or using the 307 crank in an old 350 block and the 327 pistons. Then you could use big valve heads. Ide say just stick some 305 vortec heads and on there and your cam and some fresh rings and see how that works. Maybe somebody else will chime in tho..

I apologize. I did notice afterwards that I had left out some information. Just to much to remember and list at once I have a pair of 416 casting 305 HO heads that is going to raise my compression up into the mid 9's . Because of the lack of aftermarket pistons for this 307 I am just going to replace the rings for maintenace. I have found one supplier of pistons for the 307 but all of them seem to have upto .020 milled off compression height which can cause all sorts of detonation issues in my exp. Thanks for posting...hope some more chime in as well...pictures for sure tomorrow

[Bad_Company_307]

Originally Posted by ericnova72

You can't bore the 307 block .120" oversize, you will hit water or the bore walls will be so thin it will be practically useless anyway if you don't see water.

Probably not a bad place to try the L30 305 Vortec head, I'll agree with that.

You can do some boring with this block, just not .120''(prob a typo) thats just totally insane. The 307 has a nice cast that one could bore .020 reasonably. But that is not within my budget at the moment. Sorry if there was any confusion.

[Dirty Biker]

Well they say you can bore 283 blocks .120 to get 4" inch bores, and since 307 blocks have the same bore as 283 I thought maybe you could do them too, but good to know that you cant. Anyways, I was just suggesting that because 4" pistons come in lots of different compression heights you could maybe make it into a 327. I guess you would need a rebuildable core 350 block tho from the scrap yard. I see some pistons for the 307 on ebay tho! Here is some cast ones 40 over for 150$ http://cgi.ebay.com/ebaymotors/307-CHEVY-40-OVER-PISTONS-RINGS-BRAND-NEW-/360165305554?pt=Motors_Car_Truck_Parts_Accessories

If when you take the heads off theres not a big ridge at the top of the cylinder I would just get some new rings and save that money for something else tho.

[sickolds]

you steel have to hone it

[Bad_Company_307]

Originally Posted by Dirty Biker

Well they say you can bore 283 blocks .120 to get 4" inch bores, and since 307 blocks have the same bore as 283 I thought maybe you could do them too, but good to know that you cant. Anyways, I was just suggesting that because 4" pistons come in lots of different compression heights you could maybe make it into a 327. I guess you would need a rebuildable core 350 block tho from the scrap yard. I see some pistons for the 307 on ebay tho! Here is some cast ones 40 over for 150$ http://cgi.ebay.com/ebaymotors/307-CHEVY-40-OVER-PISTONS-RINGS-BRAND-NEW-/360165305554?pt=Motors_Car_Truck_Parts_Accessories

If when you take the heads off theres not a big ridge at the top of the cylinder I would just get some new rings and save that money for something else tho.

I have seen plenty of 307's get bored to 4'' but your not going to bore .120'' thats not something I recommend. Most 307's that get rebored have become a headache in my exp. 307's are a stroked 283ci. They have a 3.875'' bore and a 3.25'' stroke. I plan on just getting new rings. I have taken the heads off and everything looks fine for just a piston ring replacement. The compression height on those pistons are still going to be .020 off which will in end mess with detonation. Its a tricky ordeal with these 307 aftermarket pistons for sure I personally just recommend getting the bore/block dunked and rehoned and cleaned up. Replace rings and your golden Thats my plan of attack at moment.

I can say that I am having a tad difficulty find some L30 305 Votec Heads as crazy as that sounds. I dont want to have them shipped cause the shipping is more exspensive than the actual heads. Typically you can get them at just about any junkyard...but the ones locally are zilcho as of yet...which means...perhaps I should just stop being fruggle and spend some extra dough on some reallly good heads.....hmmmmm

[chevy1500z71]

Originally Posted by Bad_Company_307

I have seen plenty of 307's get bored to 4'' but your not going to bore .120'' thats not something I recommend. Most 307's that get rebored have become a headache in my exp. 307's are a stroked 283ci. They have a 3.875'' bore and a 3.25'' stroke. I plan on just getting new rings. I have taken the heads off and everything looks fine for just a piston ring replacement. The compression height on those pistons are still going to be .020 off which will in end mess with detonation. Its a tricky ordeal with these 307 aftermarket pistons for sure I personally just recommend getting the bore/block dunked and rehoned and cleaned up. Replace rings and your golden Thats my plan of attack at moment.

I can say that I am having a tad difficulty find some L30 305 Votec Heads as crazy as that sounds. I dont want to have them shipped cause the shipping is more exspensive than the actual heads. Typically you can get them at just about any junkyard...but the ones locally are zilcho as of yet...which means...perhaps I should just stop being fruggle and spend some extra dough on some reallly good heads.....hmmmmm

www.car-parts.com , search the local salvage yards around your area. youl never waist your time looking on ebay or craigslist for parts like this again. i dont think it will alow you to put "the moon" in for your area tho lol

get some pics up as soon as ya can, im interested in this build for sure.

[Bad_Company_307]

Originally Posted by chevy1500z71

www.car-parts.com , search the local salvage yards around your area. youl never waist your time looking on ebay or craigslist for parts like this again. i dont think it will alow you to put "the moon" in for your area tho lol

get some pics up as soon as ya can, im interested in this build for sure.

I have been. Perhaps you missed my above post?
I live way out in the "boonies". So I really dont want to throw money to shipping cost. Unless I am going to by aftermarket performace heads of some assortment

I have 3 junk/salvage yards within 60 miles, I am wanting #416 castings of the 305 Heads with 58cc chambers which are typically a dime a dozen. But none of my local junk yards have any at the moment as of yesterday so, idk. Perhaps in the morning I will just wake up and purchase some aftermarket heads...I need to stop being fruggle after all

I will have pics up by tomorrow

[chevy1500z71]

alot of salvage yards ship for free to a business...

i remember i was trying to save money on heads when i was building my motor. the thing is, the heads are really the most important thing in determining how well the motor is going to perform, its worth the money to get good heads, i ended up just getting some dart iron eagles for mine. go aftermarket, youl be glad you did.

[Dirty Biker]

well to bore a 307 to 4 inches would require .120, but yeah just get new rings and a light deglaze. Now I am not sure that after market heads you are likely to find will work for your 3.875 bore unless you notch the cylinders for the valves to not hit, I think people have done just that on 305s tho. You could get old school double hump heads tho if you can find them where you live. Thats why I mentioned the vortec 305 heads. I have seen several sets of double hump heads go on Craigslist around here lately for less than 200 bucks, I would like to have a set but no money right now

[ericnova72]

Originally Posted by Bad_Company_307

I have seen plenty of 307's get bored to 4'' but your not going to bore .120'' thats not something I recommend. Most 307's that get rebored have become a headache in my exp.

Uuuuhhh... .120" over on a 307 is 4" bore(well, 3.995" nominal), so how do you figure they were going to bore it to 4" bore... but not .120" over??

Some years of 283 blocks will take a .120" overbore, but even in the correct years it is a crapshoot without a sonic check to see how thick the bore ewalls are first. Back in the day when this was common, about 1 block in 3 coming off the boring bar was junk due to being into water, it wasn't a sure thing just cause you had the right year block. Finding a 307 that will bore to 4" would be like winning the lottery.

Glad you love them, just leaves more of the 350 and 400 blocks for us performance guys who want power.

[DoubleVision]

I got nothing against 307`s. They can be made to run hard and circles around a 305, but you gotta know what your doing. They were given a bad rap by the public for the following reasons: They were made as a economy engine and not for performance. They came with wheezer 8:1 compression, 2 barrel carb, low spark timing, single choked exhaust, small valve smog heads with large chambers for a lazy burn. In the late 60`s the common 300 horsepower 350 cam was being used in the 307, there was a bad run of these cams that made there way into 307`s, the cams went flat taking the engine out with it.
Another famous rumour about them is they were not casted with the famous 010 020 indicating tin and nickel in the casting so they wore out quickly and this isn`t true, I`ve had two 307 truck engines that were both 010 020 blocks. Since the aftermarket is lacking on 307 pistons and all you can get is the crappy rebuilder destroked .020 jobs, you have to work to your strengths, if the block can stay standard, keep it standard and reuse the factory pistons. Clean them up good and rering it. hone the block and scrub the bores spotlessly clean. If the block must be bored then the only option is to have it decked to get a decent quench out of it, I would have it decked .020 at a max. If it`s not decked the pistons will wind up so far down in the hole it`s almost a waste of time to get a decent burn out of it. With a tight quench and a good chamber you can squeeze in compression in the high 9 area. The rest of the pack is matching up the rest of the combo to make it all work together as a team, that`s where performance is made. If it were I, I`d dump the 600 carb and use a Quadrajet. This is a article on a 307 you may like:
http://www.superchevy.com/technical/...nce/index.html

[Bad_Company_307]

Originally Posted by ericnova72

Uuuuhhh... .120" over on a 307 is 4" bore(well, 3.995" nominal), so how do you figure they were going to bore it to 4" bore... but not .120" over??

Some years of 283 blocks will take a .120" overbore, but even in the correct years it is a crapshoot without a sonic check to see how thick the bore ewalls are first. Back in the day when this was common, about 1 block in 3 coming off the boring bar was junk due to being into water, it wasn't a sure thing just cause you had the right year block. Finding a 307 that will bore to 4" would be like winning the lottery.

Glad you love them, just leaves more of the 350 and 400 blocks for us performance guys who want power.

I apologize. I have certianly read the postings incorrectly. I agree with the overbore. I have had sonic wall testing done and its just to close for comfort, IMO. I think alot of time overboring can cause to many headaches down the road, so I generally frown upon it. Especially in my area where machinist are a very rare breed. I am sorry that you believe only a 350 and 400 block are used for performance. You are surely mistaken. Check out youtube, there are plenty of 307 being dyno'd and tricked right out to the gills. If you think that 307 can not make decent benchmarks or be a performance engine, its probably a personal thing with you. Perhaps you have had your doors blown in once to many by a 307 I can understand your discontent with the 307, but to say its not a performer is not accurate in my opinion. Sure the 350 and 400 are, but how common are those?? Just how many people take the easy route and use a 350 or a 400? Most do, its cheap, lame, easy, and I care not to be like everyone else and have a lame 350 or a 400. I enjoy having unique motors that make people wonder....what is under that guys hood