IIRC the comp 268 cam is to small for the compression ratio that engine has, unless the heads were removed and were reinstalled with the thicker composite gaskets? Even then it may make your dynamic compression to high? I think I read here somewhere that even though your gas(gas from Europe) has a "97" octane rating it is only equal to around 91 US octane rating so you may not want to set your dynamic compression so high running the comp 268 will make it. On the other hand, if the engine was rebuild with the cheapest the jobber pistons the engine could have less than 8:1 compression so you may want to do some investigating. The engine is "69 dude"(movie reference) which makes it over 48 years old and you don't know what has been done with it before you got it. GL
Don't bother with those cam bearings, just get the single one. It's the dual groove, dual feed bearing. It's just the front one out of the five, which on Buicks is a crucial item to pay attention to. http://www.taperformance.com/proddetail.asp?prod=TA_1559S Also, don't listen to anyone that says Buicks don't need CFM. They're applying Chevy logic based on the same cubic inch. The Buick just needs more cfm. Plain and simple. Edlebrock carbs just run terribly in general, and especially so on Buicks. That Holley will be fine enough, but do consider getting a quadrajet. And an AFR gauge. It'll make tuning a qjet a breeze. Pics are of the bearings I bought. I bought the set of 5 for 90 bucks (74.75+ shipping), as my engine is out of the vehicle. And as stated above, the Comp 268 will raise your dynamic compression ratio quite a bit, which is what really matters compared to static compression when talking about what grade of fuel an engine can run on. That cam is designed with the chevy principles in mind, that is good flowing heads and exhaust. Buicks just don't have that.
And you won't find ANY of TA's stuff on other sites. Not even on ebay. It's just not how they operate. Their stuff is made by them, or very closely monitored if made by outside sources. In the US of A of course.
I did a little diddy with a compression ratio calculator, and with a .040 headgasket (standard replacement in gasket sets), and your engine comes out like this: 9.52:1 static, and 7.8:1 dynamic. However, if it has the .020 gaskets, it comes out to be 9.94:1 static and 8.2:1 dynamic If you have the thicker gaskets (like the one's included in that kit you listed), I believe you'll be fine. But that cam does like headers, and it's a guaranteed 30hp gain.
thanks again for the replies. I really don't understand the bit you guys are talking about static and dynamic compression and all that, so need to take some time to read about it. So maybe I'll go with the comp 268 cam, bolt the 750 cfm on it and see how it goes, then maybe if is really bad I can buy the headers at a later date.... trying to spend as little as possible, just the essential to get this running properly at the moment. Could just spend the money on a set of pushrods, but seeing as it's open I dont mind spending say 500 dollars to get most of it renewed now. Also, another thing this engine always had was a floating idle, not sure if this is vital information for what we been talking about? i remember when putting the timing gun on it, the line would float a bit, would not stay still on one marking.
Tuneup kit for the distributor might be in order. See if the vacuum pod will hold a vacuum. Did you check the timing with the vacuum advance disconnected, and the line plugged? Headers are not a necessity, but it does make a difference, as it would with any engine. Dynamic compression is what the engine creates as it's running. Static compression is what the engine has on paper, given the measurements of the combustion chamber, piston dish size (or dome, dish in this case), etc. http://cochise.uia.net/pkelley2/DynamicCR.html Here's a lil article about it to give you a better idea.
Thanks for that MrSony. that will give me some reading this evening.. The vaccum pod is brand new, replaced that maybe 2k miles ago. I also fitted an electronic ignition to it. when I was checking the timing I had the vaccum disconnected and line plugged. Another thing... before this rattling noise from the top end, and bear in mind this went from not much noise or none at all to an all mighty rattle while parked at the workshop. the only thing I done was take the dizzy out to fit the electronic ignition, I did mark it where it was, so I'm pretty sure it went in the same way it came out, is there a mark or something specific to do when putting it back in? would putting it wrongly cause the rattling I got at the top end? Just trying to think if I done something wrong.. also need to check rocker arm buttons, read another thread someone had a top end rattle and those buttons were missing. Also handy to have read that, because it explains there the slop on the rockers when the engine is off. when i checked it i thought "these here feel soft", but of course now understand it was because the oil went down and so taking the pressure of the lifter. Just been adding parts and it all comes to 500 dollars... so about £380.. that's not too bad. still need to take in account how to get them here though.
Im an American dude living overseas so I can feel your pain about getting parts. Do yourself a big favor a put a chevy engine in there...
I'd email TA Performance (probably won't get a response until Tuesday) and see if they do international shipping. I imagine they would. But being only 4 states away I wouldn't really know. Distributor wouldn't cause the noise unless it's physically broken, and then it probably wouldn't run. That rattle was probably, and most likely, the bent pushrods. I bent a single pushrod in my old thunderbird and that was as loud as a rod knock. Floppin around in there.
If you know how to jet and work a Holley to get the correct metering then use the Holley. Unless it's vacuum secondary, then they come in late.but you still need a Holley adapter for are flow is not optimized for that carb. I would do the cam bearing first if you had good oil pressure. Pump and plate isn't needed but I would suggest pulling engine and drilling out oil pickup passage to 1/2 inch and getting a melling 20-IS5 5/8 pickup screen . Get the harmonic balancer rebuilt. Cylinder heads are 58 cc not 55.
Thanks all for your words of advice and suggestions. I'm armed with a list of parts, going to see my friend this evening with this list and see what he can get... I know his answer is going to be stick a chevy engine in it. but I dont have money for that kind of thing.... and this engine is/was fine for my truck and the way I drive it. I will be back with more updates. thank you!
You have to draw the line somewhere, whether it be due to finances, skill level, tools (or lack thereof), or parts availability. If you're pretty happy with what you have now, why add more headache to it with extra complications and unknown outcomes? You know for sure it'll work fine with a freshened up OEM setup with the least amount invested (money, time, skill, etc.). I guarantee you it will wake that 350 up and make it behave properly. With the proper tune, it'll smoke those tires on the back of that truck like no tomorrow. No need to kill a rabbit with a cannon.
...and as far as slapping a huge carb on it, sure it'll work fine, and even make a bit more power at higher RPMs... is this something the truck needs? or would you rather have your torque band wider and further down in the RPMs? With the setup I described earlier, you'll have plenty of grunt on tap from idle to 4500 RPM, with it concentrated between 1500 and 4000 RPM. Aftermarket cams (even mild or 'grunt' type grinds) require better oil with extra ZDDP additives if you want your valve train to last or even survive break-in. The reason behind this is the intensified ramp profiles the lobes have in order to gain that 10-15 hp over the stock cam, but it does come at a price (not just monetary). You'll also need tighter valve springs over stock if you want the valve train to be stable above 4000 RPM, which of course exacerbates the wearing characteristics and makes the extra oil additives even more necessary. You might get away with it for a while, but don't expect it to last much beyond 50,000 miles (if that). If you drive the truck a few times a month in the summertime only, then you could get 20+ years out of it, of course. Also to consider are the bearings and rings. Changing the stock cam to an aftermarket cam will often change the valve closing to an earlier location (mild or grunt cams), increasing cylinder pressure. Even adding larger carbs will do this at higher RPMs. This will put added stress on the existing rings and bearings and could cause the engine to have issues later on down the road. This assumes you do nothing to the bottom end of the engine (rotating assembly). Lots of things to consider, and I'm sure there will be others here who disagree with my assertions. I'm used to that. lol Pros and cons abound when dealing with anything in life. You just have to match the parts with what you intend on using it for. Best wishes to you.
Right gents, many thanks for your replies again. and thanks Gary Farmer for your last posts, something to take in consideration. I dont do much mileage on it, probably about 2k miles a year or so. but certainly things to think about, specially the pistons and rings as don't fancy taking the whole thing apart. So yesterday went to see my mate with the hotrod shop and showed him the list of parts. He doesnt get anything from TA, so I reckon we will be stuck with ordering parts from summit and speedway. I will email TA to ask for international postage, but I might only use them for the smaller parts, the cam will have to come through my mate via summit or speedway to save on postage and import tax. and talking about him... he's only used to work on chevys and fords, he's had the business for 30 years now building and restoring hotrods/classic american cars, including the engines, but only having built a couple of Buicks he might miss some of the facts you more experienced people know. He was telling me that over the years only had 2 cams failing on him and they were comp cams, so he advised to get something else and just get the parts instead of a whole kit. he also said he doesn't like how the in/out on the elevation and duration are same, he prefers cams with different numbers (I don't know the tech name of this! lol) I appreciate all your advice on the comp cam, but if I get it and then i'm stuck i'm on my own... if I follow his advice, then I can say "well.. you said this was good", if you know what I mean? So he recommended a Lunati cam, he has used this brand before in many engines, although majority he uses crane cams. This one more precisely - https://www.summitracing.com/int/parts/lun-10920701/overview/make/buick This cam has a 470/484 lift, will I still be alright using stock length pushrods? I believe I read stock length was only good up to .480? Do you guys think this cam will be alright? Also, can I use standard valve springs? My friend said he will test the load on the springs to make sure they are still ok. We are then thinking of getting a timing chain, hydraulic lifters, gasket kit, etc all separate and coming from summit. Can the oil pump be rebuilt with the engine in the truck? I will probably end up ordering the oil pump bits (rebuild kit and pressure regulator) via TA and hope postage and tax won't be too much. thanks once again to all. I'm sorry I'm kind of going a different way now with the Cam, and feel like I've wasted all your time by doing so, but trying to pursuit all avenues to make this cost effective..... I have also taken some photos of the intake manifold and rockers yesterday, as promised to do that.
I would get a booster plate for oil pump . It should come with springs. If your oil pump was working well no real need to jump in there and make it worse. The lunati voodoo cams are not all that and have heard of them wearing fast as Gary mentioned these are really aggressive ramp profiles. And with any cam over stock your valve springs are junk. They are over 40 years old and designed for 380 lift. Not 480. You need springs. Although rover springs may work as it is both Buick design. As with some oil pump parts. You would need to search it. Pushrods should work but should be measured to confirm. Get a distributer recurve kit. Should not be expensive.
That's the thing, I dont know as don't have an oil pressure gauge, but there was oil at the top of the rockers, so at least it was getting there. If it is possible to fit new rebuild kit in the oil pump without taking the engine out then I would do that while I'm at it. Been trying to find valve springs for a 480 lift and can't find any, not even on the TA website. in regards to distributor recurve, that's the little different springs you can get right? I have some of those, never used them though.
See if you can get this one https://m.summitracing.com/parts/cro-50258. TA springs are good to about 520 depending on setting spring height. Oil pump is external just like rover. If your changing cam you will have oil pump off as it's in front cover. you want the lightest (gold color) distributer springs. You don't mention trans or rear gearing. Makes a big difference in performance. As with most cams, a torque converter change to match the higher rpm range may be needed for automatic trans. You should atleast get a oil sender and make sure warning light works. But a gauge would be better. Rover springs should be similar as they derive from same design engine. You will need the correct 68-69 lifters and pushrods. As it affects oil pressure to rockers and the rocker ball seat. May be best to get TA parts there or confirm with supplier they are correct. You will want cam break in additive.
Hi Alec, thanks for the above. yes, could also get that cam, anything from summit or speedway I can get over here easy. That cam had been suggested on the previous page, but I discounted it as it wasn't part of a kit. but seems like now the best option is to go for something not in kit as the only ones in kit form are from Pro-Comp and my friend is not keen on them. the transmission is a TH350, rear axle... is a 10 bolt LSD... not sure on gearing. I dont really need it to be stupid fast, just a bit more grunt from stock when say cruising at 30mph and then booting it till say 60 and that's it. Where I live is all country roads, for an european size car, so you don't really want to go mad everywhere... I'll try get a whole list of parts again this evening and see what I can come up with. this is getting really difficult as not all parts exist on the websites..
The springs and lifters kit is separate on the crower. But should be obtainable. And would be best for warranty issues if any arise. A 2500-2800 small block rated torque converter would be decent for the lower speeds you mentioned. But I would sort out the engine first. Crower cam is abit smaller but more then proven in its design for the Buick. Advancing it 4 degrees brings up low end grunt as well as dynamic compression as mentioned before. Retarded 4 would be good if you had alittle more compression and like higher rpm range. Springs https://www.crower.com/valve-springs-1-405-tungsalloy-dual-826.html Lifters. Not sure if they are correct for 69 but crower lists them https://www.crower.com/hydraulic-lifters-buick-215-300-340-350-v8.html
