My Questions, Ideas, and Ramblings About a High(er) Powered 350.

Alright, everyone. Here is the deal. I have had my 72 Skylark for almost a year now. She has served me very well as my daily driver. Summer is coming up and I will be done with school for 3 months and that means it’ll be time to make money. I will most likely not be taking the old girl to school with me in the fall so she will basically be a good weather, summer, and weekend cruiser. I am also looking for a beater to drive in the winter and bad weather.

I’ve been reading a bunch about the 350 in the past week and I have run through many ideas in my head. I have grown a little bored with the stock 350 and I think it’s time to give her a little bit of flavor. Now I’m not talking about slapping on twin turbo’s or anything like that (though I sure would love it), I’m talking about getter her up to around 300 hp to she’ll be a little more mean and at the same time maybe a little more reliable. :3gears: I want to do as much of the things as I can because I don’t feel like spending 3 times the money just so some shop can do it.

I bolded all my questions to help you out a little.:TU:

The first thing that comes to mind is making it more reliable. So while thinking about this my goal is to totally take the engine out take everything apart, clean it, lube it, replace all the seals and gaskets, then put it all back together to make her like new again. I should probably add that the Skylark has about 85,000 on it, and as far as I can tell has never been touched as she sat for about 15 years. I am not sure if this mild rebuild will happen this summer or the summer of 2011, but I’m pretty sure I want to do it relatively soon. This project would also include things like replacing ALL the hoses to make sure there are no leaks, replacing the bolts for the water pump and alternator bracket as some are missing. What company you guys suggest I buy the all new gaskets and seals from? Should I pursue this project?

The mild rebuild would most likely only get me back to bone stock, so the next thing that comes to mind while hunting for a little power would to be head porting. I’ve read a little about this and I still have a lot to learn. I know the reason for porting heads is to get better flow, which would obviously mean more horsepower and torque. What about brand new heads from TA? Do new aluminum heads come pre-ported? How much horsepower/torque gain am I looking at to port my stock heads, and about how much does the average machinist charge for a quality-porting job?

Another thing I’ve long thought about is adding headers (and maybe exhaust cutouts?), but the extraction of the manifolds scares me (along with the prices) a bit so I’ve been putting it off for a while. I’m most likely going to buy the TA Performance chrome headers when I do. But apart from the cost and manifolds, my stock AC system is kind of in the way- and not just in the way of headers, but a few other things too. And I know I’ll need a new line from the radiator to the transmission, and where do I get that? I’ve read you need to correctly depressurize the AC system: How? Where can I find a delete plate for the firewall? And about how much horsepower/torque gain would I get from the headers? And what do you guys know about exhaust cutouts?

A replacement camshaft is what I have been most interested in and that’s also what I’ve done most of my research about. I have become fond of the TA Performance 413 hydraulic cam. But I have also read that it suggest I have a compression ratio of at least 9.5:1. So I was looking into some other cams. I looked at the TA Performance 310 hydraulic cam, which also suggests a comp. ratio of at least 9.5:1. Is a hydraulic type camshaft a quality cam? And I have to admit that I love the way cars sound, and that was my main reason to start looking at cams, because I am looking for a real nasty choppy sound, so whatever cam I get has to be choppy. I have also looked into Comp Cams and a few other companies, but I just like the fact that TA is specifically Buick and that they’re involved on this board. What all will I need to replace- lifters (roller or flat-tappet?), push rods, rockers, timing gear and chains, valve springs? What tools and parts will I need for an in-house cam replacement? If not ones already mentioned, what other cams do you suggest?

The cam topic brings me to my next topic: Compression ratio. I did some reading about compression ratio today, and I’ve also known for a while that Buick made a high comp. ratio 350, so I know it can be done. What is the best way for me to increase my compression ratio, and how do I go about that? And what horsepower/torque gain would I see?

I read on a thread a while back that a shift kit is a good thing to look into. I think I understand the idea- to make it so the transmission is only in 1 gear at once and to prolong the life of the trans. Am I correct? I also read that shift kits can be hard on transmissions, which is kind of contradicting my definition. How would I go about installing a shift kit, and what gains and losses would I see?

Last second questions: Where can I find a hard line for my oil pressure gauge? What kind/model of oil filter do I need? Tell me about a Stroker conversion. Is a lot involved?

After all these I think I would be looking at a pretty mean street machine. Is there anything else that you guys suggest?

Now I don’t expect one of you to answer every single question, but more like if you specialize or just want to give your two cents then go ahead and answer. Thank you so much for any information given. I hope I am headed in the right direction and that one day I’ll be an elite on this board. :beers2:

 

Ok im in the same boat as you. I have recently tore my motor apart to clean up some issues as well as get it to run low 13's. Im not the most experienced guy here, but i have picked up a lot on this bored.

With a motor that sat 15 years its a great idea to change everything as long as you have the time, money, and are willing to listen to everything the guys say on this bored... you have all of the greatest buick minds at ur disposal around here. As for gaskets i have just used felpro for most things, some gaskets do have to be purchased from ta performace.

Porting can cost anywhere from 500 to a few thousand depending on how much porting and head flow you want done. Porting is a slow tedious process that takes some skill...which is why the pice is so steep. For a basick 500 dollar port job you can look to gain 20+ hp with a nice motor setup.

I have headders.... installed them with the motor in the car, it took my dad and i about 3 hours. It wasnt fun but possible. I did not relocate the tranny cooler lines, i simply bent the, a bit so they were away from the headders then wrapped them with the heat resistant wrap you can get from most autoparts stores which will; repel up to 2k degrees i believe. I have yet to have any heat related issues. With headders you can expect to get about 20hp. You will also need to have an exhaust shop modify your existing pipes to fit the headders. While your at it i recommend you cange to 2.5 or 3in pipes and new mufflers.

Im out of time now i will finish up later.

Good luck!

 

What did you wrap the heat resistant wrap with- the headers or the radiator line? And I do already have a true duel with 2.5" pipes, and I'm thinking about going up to 3" if I get a little more power.

So headers and a basic porting job are both about $500 and they both bring in about 20hp. For now I'll probably choose headers. Maybe in a few years I'll get the heads ported or even new heads.

 

No alumnum heads are available at this time. Leave it alone until they are on the market if you do not want to go the turbo 350 or 455 transplant route.

Here is a compression versus horsepower discussion:

http://www.v8buick.com/showthread.php?p=1573024#post1573024

 

Ok, Jim. So the vibe I've gotten today is don't go for higher compression, it'll just be a road full of vendors taking my money (not that that's always a bad thing). And me being only a student right now that road probably isn't the one for me. So I guess that brings me to what lower compression ratio camshaft would be good for me? I want it to be streetable but still capable of taking down a ricer or two.

 

Sure a nice hydraulic cam from TA would be great I suggest a TA212 for you.

Replace cam bearings with TA grooved bearings, replace camshaft, lifters, valve springs and retainers as well as timing set.

I suggest having the engine torn down and assessed by a machinist and have them tell you what has to be done as far as machining. You can not simply take it apart clean it and put it back together. The machinists have the equipment and experience to give you a detailed analysis of what need to be done to get the engine within spec on all bearings and bore. Once the engine is torn down many details of its past disappear, many machinists prefer work on engines they tear down themselves.

Changing pistons is the best way to gain compression, go for some custom forged pistons that are light and strong. Keep in mind that raising the compression will require higher grade fuel. You can mill the heads easily to get to 9.4:1 with the stock low comp pistons but any higher requires custom reliefs added to the piston to keep the valves from hitting the pistons.

Notice how my pistons have reliefs for the oversized valves to allow any camshaft to be used.

Summit has copper line for the oil pressure gauge.

Yes stroking is expensive and complicated with this engine.

http://www.v8buick.com/showthread.php?t=194272&highlight=stroker+350

I suggest getting your engine torn down by a machinist rebuilt as needed. Have the heads ported and rebuilt with oversized valves and quality valve job. Use headers and your 2.5" duals. Combine the right cam with your compression and desired rpm range. Top that of with a custom jetted carb and have some fun.

 

Would a normal propane torch be enough to bend the hard line from summit, because that's something I need to do asap.

 

the 1/8" copper oil pressure line is so soft it will practically bend itself. Your little finger is all that's required. Make sure you keep it away from unfriendly surfaces like sharp sheet metal edges for durability.

Devon

 

Do you think 6 feet would be enough?

 

Should be just fine.

One trick for tubing protection is to slide length(s) of vacuum yubing over the copper line before you install the fittings. Just slide the rubber hose to the areas that need protection from sharp edges. Make sure you use a rubber grommet in the firewall if you choose to drill a new hole for routing the tubing.

Dit you use some brass fittings to adapt both the oil pressure gage and original warning light sender? You really need to keep the water temp and oil warning lights functional.

Devon

 

I haven't messed with the oil gauge at all other than putting it in the bracket that the three gauges are on (water temp, oil pressure, and volt meter). When I was installing the water temp sensor in the front drivers side of the intake the sensor that was there previously snapped off. So I'm not too sure what to do about that. But the water temp gauge still works fine.

 

It's a good idea to keep the lights working (if your car had them) as well as your aftermarket gages, something to consider.

Devon

 

what exactly snapped off and what is still connected and works fine?

also


The oil pressure sending unit is way in the front on the passenger side. If you are putting the oil pressure gage on the drivers side corner it will take about 10 feet. I just installed one and needed two summit copper kits to do it. Autozone as them for 5.99 each. Youll need a join fitting as well. I suggest measuring exactly how long it will be to where you are mounting the gage. Its longer than it looks.

 

I do have the idiot lights.

I tried to attach pictures of the part, but I'm not sure if it worked.

EDIT: Yeah, it worked.

 

Looks like some kind of electrically controlled vacuum valve, not a water temp sender.

Devon

 

The only thing attached to it was an electrical female unit with two wires coming out of it. There were no hoses attached, which to me looks like there are two places where they could be. Nothing has changed in the performance of the car since I did that back in July.

 

Someone more familiar with the early '70's emissions and/or vacuum hose routing stuff will know more about it. Doubt you're missing out on anything, likely stuff you'd want to be removing anyway.

Devon

 

Alright I've got a couple more questions for the night.

You guys suggested TA's 212 cam. It has a suggested comp. ratio of 9.0. I thought a stock 72 350 had like an 8.0 comp ratio or something more like that?

And if that ratio is ok, then would something like the 284-88H or the 290-94H work? Because those also recommend 9.0:1.

Can bearings be installed without taking the entire engine out? Because if I'm doing just the camshaft this year I won't be taking the engine out.

 

Ok heres my 2 cents budski's.

You want this to mostly just be a cruiser and weekend blasts right?So start with a tear down by a machinist so they can see what needs to be done if some overboreing is need or just a good honeing of the cylineder walls will be fine.

From there as sean said pick a cam that is good for the kind of driving you want to do and the rpm range you are mostly gonna be scootin around at.

Now as far as compression goes you can get it up buy milling the block or the heads or find some high comp pistons.When I rebuilt my engin in 08 the machine shop I used for machining they asked me what kind of pistons I wanted low comp or high so I went with the high because at the time I was just hoping pour nitrous down my cars throat till it blew up lol.
I say stay low comp so down the road you can turb/charge it

I wouldnt just focus so much on just the engine though.I mean get it looked at change out gaskets and new cam and bearings and such but swapping out the peg legger to a posi will help get her up and moving a little easier.I have 3.73's I hear that 3.42s are the best all around.

Also power tuning wakes her up too well I think thats about it.I say get the 212 cam and get some gears and posi and then rip em up!

 

I'd leave the engine alone. Buy TA headers, X pipe, and anything else you may need to get the exhaust out the back, also move the trans lines away from the exhaust pipes. Take off the air pump (if it is still on). Get either an MSD or HEI electronic ignition. Save your :dollar: and enjoy your car.:bglasses: That will get you over 300 hp.