Buick 350 engine from Perú, help for increase power and torque.

Discussion in 'Small Block Tech' started by César Machicao, Oct 19, 2021.

  1. Hello guys, greetings from Perú

    I showed you my current project a few days ago, a 1970 Skylark with a 350 2bbl engine, found 3 years ago. I have some expectations about the possibilities of the improvements, but with some obvious limitations for the area that I live.

    The engine was started a couple years ago, when the car arrives to my city from the area that been found it. At this moment, the body has been worked by a local body shop and the powerplant was separated from the car. Once finished de bodywork I thought to work in the wiring system and then the interior. Once all this equipment was installed, I have plans to continue to the engine.


    I'm looking for a 9:5:1 compression ratio, these particular engine have possibly 9:2:1 C.R., the short block is in STD bore and possibly the cylinder heads as well, it would be awesome if you guys could give your point of view if is possible to work (in the case that the block have no requirements of reboring) with the stock pistons or maybe pass to other type of pistons models with the mentioned compression ratio, the correct piston rings for this particular application and if is also possible to build with stock replacements bearings for connecting rods and mains or maybe pass to another options.

    For the cylinder heads, due to the particular conditions of this part of the world and the notorious limitations for find all correct parts for a high performance rebuild work, I was thinking make a porting work by myself, but it will be the first time that I do this kind of work, in the local machine shops here nobody knows about this particular job. If any of you may have some guidelines about the proper way to do it (specially for the 350 iron heads) I will very grateful.


    And also, It would be fine if I use an hydraulic camshaft with solid lifters? I was reading about using the solid lifters with hydraulic cams and apparently is possible with some changes in the lash of valves, but due to the rigid assembly rocker arm of the 350 iron heads it's necessary use a. New adjustable assembly rocker arms or b. adjustable pushrod kit. Perhaps the new rocker arms would be the best way? Or maybe the adjustable pushrods? Consider the high price of rockers, maybe if is no problems using the adjustable rods would be fine? And what about the springs, guides and everything related? Please let me know about some similar experiences about it.


    I spoke with a person of TA performance about the correct parts for my project, and they recommended a solid cam (TA112S-350) with a solid lifters kit, an adjustable pushrods kit, a couple of headers (TA2010CH), a dual plane intake manifold, and they recommended a 600 or 650 max. cfm for the 4bbl carburetor, probably I'll put a carter quadrajet, or may you can advise me about another carb with a good response, and asking for possibility of porting the cylinder heads, they told me that's not necessary for my application because with the parts that they recommended would be enough for made near to 350 hp an equal number of foot pounds of torque.

    About the original valves, assembly rocker arm, rocker arms, nylon buttons, shims, valve keepers and any hardware of the valve train Would be necessary any change in the case that all these parts are in good shape or will be preferable some changes for improvement in the functionality? Simple or Double Springs for valves? Maybe a Double roller timing set would be fine for this particular combination?

    I would like to know in your experience that with these particular parts I'll be around the 350-365 hp with a 9:5:1 comp. ratio? Or maybe will it be necessary porting the cylinder heads?

    For this particular combination, would you recommend some changes in the oil pump or just maybe acquire a stock replacement and adding a proper gear set?

    About the cooling system, would be better adding an aluminum radiator with an electric fan? Or just stock replacement?

    I guess that the ignition system was the original with points, any suggestions about some improvements of this system (upgrade the distributor, coil, etc.) or maybe migrate to an advanced ignition system? And about the stock alternator, it would be rebuilt with some kit for that? Any related advices?

    Thank you so much!

    César Machicao
    patwhac, Reidk and PGSS like this.
  2. PGSS

    PGSS Silver Level contributor

    The compression on the 70 350 2 bl might be closer to lowish to mid 8 to 1 instead of the rated 9 to 1??

    I don't know what your plans are or talked to TA about but i'm surprised the "salesman" recommended a somewhat? strong solid lifter cam and adjustable everything for a motor with stock heads or slightly ported even. Too many issues might happen with constantly setting lashes, maby striping threads and needing extra hardware, plus waiting forever for parts in Peru.
    It mentions you would also need a 2500 converter for that cam which also leads to needed better rear gears.
    I would just find a nice hydraulic kit with their stage 1 springs upgrade.

    Lots of great small block guys here which i'm not.
    They should chime in soon.

    I do see you posted pic's from "How to build Max Performance Buick Engines"
    The 350 build in it with a good amount of porting in the heads didn't quite make 400 hp, it was more like 390 hp. Not much difference I know..
    I also had read on another source that the cam they used wasn't very street friendly. Maby set a goal for 300 hp at first and use some good gears that are at least 3:42's.
    Last edited: Oct 22, 2021
  3. sean Buick 76

    sean Buick 76 Buick Nut

    I don’t know why TA promotes those 600 and 650 carbs they run like crap on the 350. Use a Q jet built by Everyday Performance, much better. I would use a TA-212 cam and shoot for 9.5:1. You can do that with stock pistons just machine the heads to up the compression.
    PGSS, techg8 and Mark Demko like this.
  4. gsjohnny1

    gsjohnny1 Well-Known Member

    i seem to recall the 350 wagon ran a 650 holley on it. i ran a 650 holley on mine all the way up to a 471 blower.
    stay will the stock style set up. you are not in an area where buick 350 parts are falling out of the sky.
    PGSS and Mart like this.
  5. Fox's Den

    Fox's Den 27 years of racing the same 355 Buick motor

    about time someone wants to put in a solid cam in a 350 there is just noo imagination here. I think a 112s would kick ars.
  6. stump puller455

    stump puller455 1970 GS 455

    hola ! my wife is from lima...looks like a project good luck with it
  7. gsjohnny1

    gsjohnny1 Well-Known Member

    i have a solid cam for the 671. painintheass. gonna go back to hyd
    PGSS likes this.
  8. knucklebusted

    knucklebusted Well-Known Member

    With a Buick, I would not run a solid lifter cam unless you are going for max effort race motor. Even then, why bother with solids when you can go roller for more real power?

    If it were mine, I would build it back pretty much stock except for increasing the compression ratio by cutting the heads and decking the block to get them square. Swap on a 4 barrel intake and carb with a streetable cam, maybe a TA212 or one notch higher with the 284-88H. Anything bigger and you need more compression, better gas and probably a looser torque converter.

    If you can port the heads yourself, don't go crazy. Just clean up some casting flash and clean up the throat under the valves.
    Dadrider, sean Buick 76 and PGSS like this.
  9. sean Buick 76

    sean Buick 76 Buick Nut

    Bump as your project continues
  10. Stevem

    Stevem Well-Known Member

    I can help you get more air flow into and out of your heads.

    First off the intake does not any big bowl blend work, just certain areas will help, while other will hurt flow numbers.

    There are 3 areas in specific that do need rework which I can go over with you.
    The port already has more then enough port area at the flange, so unless your intake manifold has more port area at its flange, then do not do a gasket match.

    The exh port bowl needs work, but it’s more along the lines of fine tuning then a outright rework.
    At the flange here, once again do not do a gasket match as it will only serve to drop port velocity.

    a good move if you can get the work done would be to the valve guides installed to get new valves with the smaller 11/32” stems unlike the massive 3/8” stems you have now.

    can you post up a close up shot of the intake and exh valve seat area ?
    I would like to see atleast least a 1/2” long section / picture of each.

    by the way, that grinding Burr your using in your picture you posted is for Aluminum, not cast iron!
    Using that will give you very poor control and you will likely find yourself removing more material then you want.
    Question, are there auto machine shops you have there that can provide a 3 angle valve job?

    Also if you scroll down more in this SB section you will find a post I have been making about porting a SB head.

    it’s titled “ reworking a B1382546 head” you should find it helpful.
  11. alec296

    alec296 i need another buick

    The 70 2 barrel engine was roughly 8.2 compression. Forged pistons with as close to zero deck would be best for power. The ta 212 cam with proper carb tune, and head flow with headers, can get up near 350 hp in the upper rpm. The crower level 3 cam is my personal favorite, would make more torque then hp in comparison, less bolt ons needed then, but again head flow. A well built Quadrajet is best for most applications. Quadrajet Power or Everyday Performance would be a good choice on carb rebuild .
    But sounds like you may be more interested in a 10 to 1 engine with big valves, single plane intake and the ta413 cam. Big converter, rear gears, up near 380 hp or better would be possible.
    Ta has big valves available.
  12. Hello Steve,
    I really appreciate your willingness to help me in the project. I'll send you specific pictures of the intake and exhaust valve seat area and also some images of the intake and exhaust ports as well in a few weeks when I get back to my place.

    At this moment I'm trying to find the correct parts for the rebuild process such an intake manifold, a good carburetor (Fortunately Sean helped me with a Quadrajet unit, I'm really thankful to him), the correct (and not much expensive) gasket set, freeze plugs, new gears for the factory oil pump, water pump, fuel pump, main and rod bearings, cam bearings, etc. Here we have a lot of issues finding the correct pieces for a rebuild job, mostly you can find a Chevy NOS parts, but nothing specific for a Buick engine. If you have any suggestion for a correct part let me know.

    Also, if you can in indicate me the proper grinding Burr that I can use in cast iron heads would be terrific since there's no auto machine shops with a related work in heads that I know on these areas (I've been asking for a while without results) so I must do the job myself follow articles and valuable instructions as yours.

    I'm reviewing your article carefully and take notes about it.
    Thanks a lot!

    Thank you so much for your inputs, fortunately thanks to Sean I could get a Quadrajet; for the current wait time in Quadrajet Power or Everyday Performance I was thinking in buy a rebuild manual an also a rebuild kit for my unit and make a basic rebuild job myself, Will be enough for my requirements? (That would be my first rebuild carb.) Or can you suggest me another way? About the camshaft, would you agree with the installation of a hydraulic cam instead of solid unit w/solid lifters? I read a lot of complains for the hydraulic lifters and drastic failures, but in the other hand it could happen just in High RPMs (6000 or more)?

    Honestly, I'm interested in achieve the 300 hp or just more (320) for a fun vehicle with 4 speed and probably with POSI 3.23 final ratio.

    Thanks a lot!
    sean Buick 76 likes this.
  13. sean Buick 76

    sean Buick 76 Buick Nut

    Just a note about the Q jet I sold him. It was new in the sealed bag as a stock replacement and I only used it for a few hours of run time. So it shouldn’t need any actual work other than cleaning new gaskets and float. Carbs with 100,000 miles often have all sorts of challenges like leaking throttle shafts and worm out parts.

    I would remove the crank and check the bearings for wear at very least, then decide if you are going to replace them with stock spec size or have the crank cut for oversized bearings. Of course then there is checking the mains of the block and a bunch of other items however I’m not sure if you have access to a good machine shop? In a perfect world we spend quite a bit of money at the machine shop ensuring all aspects are perfect.

    Regarding the lifter failures I think it’s more of luck vs how high the engine is revved. I use comp cams lifters, both hyd and solid in different combos. Typically we buy the cam, lifters and valvesprings from the same supplier to help increase warranty chances of there is a failure. Mixing and matching lifters, cams and springs often gives all of them an easy way to deny warranty. Most of all the break in period is most critical I think. Also using good oil and additives to help the cam live a long life are important. That being said I recently tore down three buick 350s ranging from 35,000 to 300,000 miles and all of the cams and lifters looked fine. What’s hard on flat tappet cams and lifters are steep ramps on wild grinds. The cams you are looking at are mild, not steep ramps. This is why most engine builders push the roller cams, no break in needed, less risk for them but $$$$ and there have been a lot of roller lifter failures too. For a mild cam the roller cam has a limited advantage, more extreme engines yes they have a big gain.
    Last edited: Sep 22, 2022
    César Machicao likes this.
  14. alec296

    alec296 i need another buick

    You can produce 300-320 hp 375 torque fairly easily with this engine with little work. Get compression up some . Decent cam like the ones mentioned. Tuning. Some extra head flow (porting and/or big valves) . Engine would never have to see more then 5500.
    César Machicao likes this.

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