Lil 307 that could....

[Jacfourteen]

When they kill the cash for clunker cars don't they pour in the solution in the valve cover oil fill? So doesn't that mean the solution is all over in the rockers and valve stems on that head? I thought about getting heads from one too, but was scared they were trash.

[screamin_c10]

The engine is run til normal operating temp then drained of oil. That means the heads are bathed in fresh oil. The solution is then added and is the viscosity of water quickly draining into the block from the head. The engine seizes in less than 30 seconds after startup. There is residual oil still in the oil galleys and push rod tubes etc so the thinner liquid doesn't seem to make it up there in time.

Also the "Death Juice" doesn't react with the metal or really tear anything up like an abrasive. Once the engine starts with no oil the mains get hotter than he77 and evaporate the water out of the solution. Once that happens the silicate literally becomes molten glass and seizes the motor quickly, as in right now. Its actually very anti-climactic...but sad.

But like I said I took the heads in and had them checked out before the 30 day replacement period expired. They were in excellent shape according to my machinist...

[sav300]

That 307 sounds sweet!! Nice to see something that isn't a 350, 383, or big block. Keep up the good work.


BTW love the gauges!!


Thomas

[screamin_c10]

Well it looks like I've got some retainer to seal contact on a couple of cylinders. Took me a while to figure out why I'm blowin' some smoke at higher RPMs. Weird thing is the stock Vortecs are supposed to be good to .470 lift, My cams exhaust lift is .465. So I don't know if I'm hitting the seal or if the retainer is coming really close and pushing the oil past the seal like a pump. Either way I'll be pulling off the springs and retainers to investigate.....

As Marvin the Martian once said "Delays Delays"....

[andymarkv]

Marvin Martian FTMFW!!!

Can you get offset valvestem keepers to get a little more clearance?

Man..... I had forgoten the lift is so short on vortecs.
I'll have to remember to have the guides milled down if I get a set.

[60ratrod]

Originally Posted by andymarkv

Marvin Martian FTMFW!!!

Can you get offset valvestem keepers to get a little more clearance?

Man..... I had forgoten the lift is so short on vortecs.
I'll have to remember to have the guides milled down if I get a set.

if you find them post a link. i looked for them a while back and couldn't find a damn thing! i know crane made a set but can't find anyone else that makes them

[andymarkv]

Yeah now that you mention it...... I have always heard of them, but now that I look for them.....I can't find them. And if you can't find them for a small block chevy....they must not exist!!!

*edit*

I did find these?
http://www.alexsparts.com/products/L...-UP-LOCKS.html

[screamin_c10]

I've looked at this setup from Alex's Parts:

Linky

I really don't have much of a choice now unless I want to pull the heads...again... and have the guides machined down.

Apparently his kit allows up to .550 lift on un-machined heads. I needed to get upgraded springs anyways so its a win win I guess...

The Offset keepers raise the retainer up and allows additional clearance between the seal and retainer, BUT this can cause the retainer to contact the rails on the SA rocker arms.

[Jacfourteen]

Originally Posted by screamin_c10

The engine is run til normal operating temp then drained of oil. That means the heads are bathed in fresh oil. The solution is then added and is the viscosity of water quickly draining into the block from the head. The engine seizes in less than 30 seconds after startup. There is residual oil still in the oil galleys and push rod tubes etc so the thinner liquid doesn't seem to make it up there in time.

Also the "Death Juice" doesn't react with the metal or really tear anything up like an abrasive. Once the engine starts with no oil the mains get hotter than he77 and evaporate the water out of the solution. Once that happens the silicate literally becomes molten glass and seizes the motor quickly, as in right now. Its actually very anti-climactic...but sad.

But like I said I took the heads in and had them checked out before the 30 day replacement period expired. They were in excellent shape according to my machinist...

Thanks for explaining that to me, I guess I will see if there are any left in my local yard.

[Jacfourteen]

Originally Posted by screamin_c10

I've looked at this setup from Alex's Parts:

Linky

I really don't have much of a choice now unless I want to pull the heads...again... and have the guides machined down.

Apparently his kit allows up to .550 lift on un-machined heads. I needed to get upgraded springs anyways so its a win win I guess...

The Offset keepers raise the retainer up and allows additional clearance between the seal and retainer, BUT this can cause the retainer to contact the rails on the SA rocker arms.

Looks like a good alternative, in his info he says that vortecs are only good to .460 lift, maybe that is why you are having problems.

[screamin_c10]

Originally Posted by Jacfourteen

Looks like a good alternative, in his info he says that vortecs are only good to .460 lift, maybe that is why you are having problems.

Ahh he77 whats a little .005" between friends....


Thats part of my problem is the conflicting specs that I keep reading.... I should have milled them down and been done with it when I had the other set done....Oh well live and learn.

[60ratrod]

those are the exact ones i was talking about. i read about the crane ones in one of the sa tech books that i have. but those are what i was looking for a while back

[rayfinseats]

Can you keep us posted on the gas mileage? I think it would be a good gas mileage motor.

[screamin_c10]

Originally Posted by rayfinseats

Can you keep us posted on the gas mileage? I think it would be a good gas mileage motor.

If I ever get her runnin' right....

[screamin_c10]

So the parts came in From Alex's and I have to admit these are nice quality pieces. The key to the whole setup is the custom retainer and slightly longer spring. Cant wait to get them on the heads...but for now here are some pics for those that are looking at using them....

[screamin_c10]

A couple more with some measurements and specs.

[Jacfourteen]

Looks like it makes for a good bit more clearance, can't wait to see you get it back together!

[MrBlue]

Screamin_c10,
Nice write up. Was curious about my own engine about 2-months back. We were told that the truck had a .030 over 350. However the block numbers indicate that it is the original 307. Was very sad May have to pull the heads to really see what we have, but am pretty sure we will find a stock 307. Your write up has me thinking? Put on a fresh set of Vortecs? or Maybe rebuild my other 350? OH THE DISCESSIONS!!!!!

MrBlue

[screamin_c10]

MrBlue

If you indeed have a 307, and you want a definite seat of your pants improvement then swap out your heads for a set of Vortecs and a mild cam.

I would take the heads in and have the guides machined down for additional lift and the seats machined for the "standard" chevy spring diameter. This is what I should have done originally. It will save you some headache and expense.

The Summit 1103 cam works well for me, but to each his own.

With that being said:

Build that 350 short block, as I said earlier this was a "can it be done" type of build, I personally know that I have, and will, run the dogsnot out of this little engine and would rather let it live its life under the gentler right foot of my wife in her Chevelle. My intent is to transplant it into the Chevelle once I have tweaked and tuned it in Screamin' When the bottom end finally goes t!ts up, I'll look into a roller 350 block.

Once you have all the bells and whistles done in the 350 bottom end, swap it in and bolt the same Vortec heads and intake to it. If you have the machine work done ahead of time you can run pretty much any cam up to .6 lift.

Remember I made use of what I had laying around and very little budget. With some planning you could be way ahead of the game.

Either way, have fun with it....
Bill

[capev86]

i have the original 75,000 mile 307 in my 72 burb c20. it came with a 2bbl, 3 on the tree and 4.57 rear gears. the carb was giving me a bit of trouble so i swapped in a q-jet with an edelbrock performer intake (idle-5500rpm) and changed the rear out with a 4.10 third member. it is much spunkier than before despite the softer rear and i think it will make an ok tow vehicle until i get around to putting my 406sbc in.

the 307 isn't a bad engine and certainly an improvement over the earlier 265 and 283 cid units. but i'd rather have a 305 with a q-jet and an rv cam like my dad put in his 72 burb c10 to replace the tired 350 25 years ago. the 307 is like a smaller version of the 327 (same crankshaft) which is a more rev-happy engine bettter suited to light cars running on the dragstrip, not hard working trucks pulling loads. in the trucks they tuned it for better low rpm performance and they were somewhat successful. but really, it was like trying to make a torque monster out of a honda 1.6L (only with twice the cylinders). the power doesn't really come on until the engine is screaming. to re-tune it for low rpm power means it is fighting itself and not reaching it's potential as designed.

if i rebuild my 307, i will certainly put a stroker crank in it. you get about 325 with a 305/350 crankshaft and a 354 with the 400 crank. it would breathe a bit better than the 305 thanks to larger pistons but have more torque and certainly better economy than a 350. a roller rv camshaft and a few other tweaks (port/polish work, etc) to improve durability and performance would be the finishing touches for an awesome all around small block in a daily driver friendly vintage truck.

[screamin_c10]

Well the new springs and retainers are in. Fired her up a no smoke but I haven't taken her out for a test run. The retainers were definitely hitting the seals, more so on the exhaust side than the intake. I set the lash in a hurry and will need to go through the routine again next weekend. Here are some pics if anybody is still interested....

[60ratrod]

Hey screamin, check your oil. I saw a bit of coolant in the first newest photo you posted. Don't wanna see that motor retired before its time
Posted via Mobile Device

[screamin_c10]

Originally Posted by 60ratrod

Hey screamin, check your oil. I saw a bit of coolant in the first newest photo you posted. Don't wanna see that motor retired before its time
Posted via Mobile Device

Thanks Ratrod, that's actually assy lube I used on the valve stems to keep the seals from getting tore up....

I actually changed out the oil today for 10/40 trying to get the damn thing to quit smoking...

[60ratrod]

Ok.... that had me worried for a sec...
Posted via Mobile Device

[Kidd-7]

Hey screamin any news? Is she running right yet? I have a 307 and been keeping track here, just wanting to know your status. thanks.