Thread: few chevy smallblock questions

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Hello,
after blowing up my vans 305 engine after just buying it(the seller was as puzzled as me, we just did a 20mile testrun with no issues at all ) i bought a 350 supposedly from a 70's caprice but not sure. It has castnumber 3970010 and VIN K1004CMT 18112777
If someone can give me a decode off it i would be thankfull because here in holland most do not have a clue i guess.
in time i would like to give it some more torque and hp. But i would like to do it so that the engine still can be used for daily driving and not wear out to fast. So if someone would give me some good tips ideas and maybe specific parts.
bare in mind that overhere regular gas has a 95 or super has 98 octane.
I know some here will say ugh why a van. well... i'm a vanner and if you have 3 kids and 4 great danes its kinda hard to fit that in most normal cars.
thx out front for the help.

The 70's were one of the lower points in horsepower ratings of the little Chevrolets. So, rather than a stock rebuild, do a standard mild performance rebuild. Accept the 350 in your thinking as a starter block and attack it from there. You can make an excellent driver out of it for just a paltry few more bucks than stock rebuild by being careful with your parts selection. You need to make the whole engine work together the best that it can. A properly built 350 will move that van right down the road with class and last forever. Look for horsepower output in the 325-375 range. Bottom end torque is what gets that van moving from a stop, build for that.

CMT is either a
74 Camaro 350 with 245hp 400transmission Z-28 4bbl carb
78 Impala 350 with 170hp TH350 transmission 4bbl
80 Impala 305 with155 hp TH350 transmission 4bbl

And since it's a 3970010 4" bore block, it can't be a 305. What cylinder heads do you have available to you?

.

thx for the VIN decode robot, i found that the 3970010 castingn° could be from either a 302, 327 or 350 depending what site i looked at. Overhere they said they ripped me off and sold me another 305. (see what i mean by those backyard "pros" here in holland). HP wise i was thinking to go about 350 as they used to say one HP per cubic inch so your right on the money scooter.
@ techinspector1, right now i haven't made any decisions on parts, i seen alot of talk about the later vortec heads, but would they even fit my block as its so old?
and as its been more then 6y since i been to a meeting with my own vehicle. I would just put new gaskets and new cranckbearings init for this season and start gathering the needed parts so when the season ends i pull out the engine for a complete overhaul. So theres no rush.
Keep in mind that US parts cost about double (sometimes even triple) the price you pay in the US (shipping and customs) so i need to save up a little more then normal.example i just got a enginetech gasketkit thats about 45usd i payed 80€ (about 120usd) what still is a fair price overhere.
Thats the reason i'm taking it easy buying stuff untill i see a good buy here or in the surrounding countries(no importtax then).
Theres some things i will do either to make it run more reliable or to get back a few horses.
-put an adjustable electronic fuelpump in the tank
-electric cooling fan
-oilcooler for the engine
-oilcooler for the tranny
-use two old airfilterhouses to make one with a double intakepipe and use a flexhose to get to the grille to make some sort of ram-air system
-change the front suspension for one from a chevy g30(stiffer)
-use two flexhoses from bumper to the backplates of the frontbrakes to get forced cooling on the brakes.
-lose the ugly sounding glasspack cherrybomb for a flowmaster deltaflow 40series and some descent headers
most stuff i allready have from friends

Originally Posted by Ratboy rebel

Hello, i bought a 350 supposedly from a 70's caprice but not sure. It has castnumber 3970010 and VIN K1004CMT 18112777
If someone can give me a decode off it i would be thankfull because here in holland most do not have a clue i guess. thx out front for the help.

Glad you made it to the site, it's good to see you here and I hope you enjoy your time here. I'm not the bow tie guy but there are many here who can help you out and it looks like a few already have. It must be a bear of time getting stuff to Holland!

Hang in there and keep us updated as you can.. p.s. we love pics!

70s??????????? it was during the 70s that they detuned and smogged the USA engines-----early 70,71,72 will be higher compression--after 74 cat converters, low compression, non lead fuels------------

It's your money, but the power savings of an electric fuel pump and fan just don't justify the cost.

Mechanical pumps vary their output with rpm, exactly as the engine needs. Mostly, they just work better, easier to maintenance, cheaper, more available.

Electric fans don't always work out. Personally, I've had two projects to date, where the engine just wouldn't cool, and I had to go back to a stock fan.

As I read your list of potential changes I agree 100% there are several places where you can save some money and increase your long term reliability, IMO. When you look at converting from mechanical devices to electric the power required to generate the electricity (alternator load) is going to be at least identical to the power to drive a mechanical device direct, with no energy conversion costs. Your list:
-put an adjustable electronic fuel pump in the tank - An electric fuel pump is not going to improve efficiency or reliability, and is not necessary unless you're switching to EFI. A good, OEM mechanical pump is more reliable long term and as Firebird says it's variable with rpm. Consider that when (not if) that pump motor or rubber parts fail you're dropping the tank to replace it unless you make an access panel.
-electric cooling fan - Again, your OEM mechanical fan with a good shroud will be more than adequate, and you don't have the worry of the electric motor failing at the most inopportune time. The electric fan, close coupled to the radiator, is going to actually diminish your free air flow at highway speeds, when you don't need the fan anyway.
-oilcooler for the engine - Unless you are pulling a trailer, you likely do not need an external oil cooler. Your oil needs to get up to engine operating temperature in order to "cook off" the lighter contaminants that tend to form acids in your oil, and an oil cooler without any form of thermostatic modulating control may well prevent that, especially considering your climate.
-oilcooler for the tranny - Same as the oil cooler, unless you are pulling a trailer you don't need a tranny fluid cooler.
-use two old airfilterhouses to make one with a double intakepipe and use a flexhose to get to the grille to make some sort of ram-air system - More air to the filter is always a good thing, and the ram air doesn't hurt.
-change the front suspension for one from a chevy g30(stiffer) - Good idea, if you want the harsher ride cruising.
-use two flexhoses from bumper to the backplates of the frontbrakes to get forced cooling on the brakes. - Not a bad idea, but unless you're doing a lot of extreme braking, like long, long downhill runs where almost continuous braking is required then you probably don't need this feature. A good set of sintered pads will deal with normal braking heat.
-lose the ugly sounding glasspack cherrybomb for a flowmaster deltaflow 40series and some descent headers - Good idea, but you'll pay for the Flowmaster name....

I'm not trying to be critical of your plan, but having recently come back from a trip to NZ where I talked to a bunch of gear heads I have a new respect for the costs and delays of importing parts from the USA. You're right on target to make a plan, then work that plan to the finish, but I'd suggest that you plan based on the value of the payback you'll realize and what is truly "needed" for improved efficiency and reliability.

ratboy, here's the skinny on L31 Vortec 5700 heads......
http://www.crankshaftcoalition.com/w..._cylinder_head

By the time you spend all the money that's necessary to bring these heads up to spec for hot rodding, you could have bought a set of aluminum heads.

.

@rspears i agree on most things you say, but then again i will be towing a caravan to most meetings during season and as its a double axle one i found the use of oilcoolers quite helpfull to keep temperatures within normal ranges certainly on hot summer days. then about the brakes i personally find that the brakes on vans(even the first expresses as i used to have one to small for the weight, certainly on smaller roads, i'm not a guy who speeds alot but i can floor it sometimes and found that even with good brakes they tend to start fading, and when i brake i want them to work thats also where the stiffer supsensionsetup comes in place my van is a hightop so a higher center of gravity and my gf hates the leaning out in corners :-p.
On the flowmaster part, i had a flowmaster on my express and just loved the civilized sound when your just cruizing along. and as second, in a few years the van will be running on both gasoline and lpg. i don't know if your familiar with Liquified Petroleum Gas. when it expands in the cilinders it tends to give more condensation in the exhaustfumes, so in mufflers filled with glasspack after a short time it makes the glasswool hard eliminating the silencing. Thats also a reason your allowed to remove a kat if you have one. and the pollution on lpg is about 60% less then regular fuel even with all the emissionshit on the engine removed. and is also 3 to 4 times cheaper then gas. only drawback is about 10%to 15% less horsepower but its a great fuel to run on long trips
@ firebird, what the electric fan and pump is concerned i'll keep your words in mind and will wait out how the engine reacts for now. the electric fpump idea is from the time i had a 67 mustang and had to switch to a electric pump because the OEM could not deliver enough fuel to the carb, drawback was that if i didnt start right away it would flood the carb lol(dunno if it fits or can be made to fit but would a mech BB fuelpump be an idea?)
@techinspector1 so you would suggest to get a good set of aluheads over vortec ones? any good names or brands i need to keep an eye out for?
at this time(dont have the money for it right away but still) there are a set of vortec "906" for sale for about 400€ they have been inspected and revised where needed, they say they come from a mercruiser boat engine. not that i'm buying them but just to give you an idea on pricing