newbie with 350 sp motor blues

Discussion in 'Wet behind the ears??' started by brownbomber, Sep 13, 2013.

  1. brownbomber

    brownbomber Silver Level contributor

    :Dou: I'll start out with a slap to the head on this one. first short and sweet not often have I pushed her hard but when I did the 120k motor started popping through the carb (hard accel),I suspected worn cam shaft? well pulled off carb/intake and valve covers (they were leaking anyway) didn't take long to see after cranking eng by hand three cam lobes worn bad! after rolling push rods by hand 3 had big wobble, screw it removed rocker arm assem and found 6 were badly cracked (aluminum kind) so I thought ok 2 options first hope cam bearings are good :rolleyes: install new cam old bearings (maybe one or two could be replaced)lifters, pushrods, updated rocker assem and hope all is well that ends well :ball: or yank the motor and trans and do it right.... I just didn't want to have this huge project because I've recently been diagnosed with multiple sclerosis so my abilities have greatly slipped away. simple stuff sometimes with help I'm ok anything heavy no way... so my question to y'all is should I go through with the repairs or sell it. the car is she my baby (wife says sell it cut your losses and buy one that's already done) decisions decisions?? the way I got at least $1500.00 in ta performance parts not yet install new in the box ready to go!:Dou:
  2. gsgnnut

    gsgnnut Well-Known Member

    Sorry to hear about your health issues, fighting my own too, damn glaucoma taking my eyesight. Anyway, i have some experience with the 1970 SP 350 motor. Had a 70 GS coupe just like yours, eng also tired. I did the engine completely over because the cylinders and rings were shot and she was a 3600 pound rolling bug bomb. That being said, if your lower end is ok, not knocking/smoking, and the engine is relatively clean inside ( heads not caked with carbon deposits) and most important it has good oil pressure, I would put a timing chain/ cam/lifters and STEEL ROCKER SHAFTS in it and enjoy the life it has left.

    If the engine is caked with carbonaeous gunk, which I suspect it is DNR- its a waste of time. The cam likely wiped out due to blocked oiling passeges do to crud. There are other options. I guarentee there are others on this site that have good used engines for sale for less money than buying new cam/lifters and timing chain and rockers that you could swap in on a saturday and drive to work on monday. I even bet someone near you would help you do it- If you lived in westfield I certainly would. I help the local HS kids with restoration and engine work on their project cars fairly often because they dont have the $ and their parents are pretty clueless (the GS gets me a lot of attention in my town)

    Usually 43 old original engines are caked pretty bad with carbon crud from lack of oil changes and poor quality oil during the 70's. now and then you find a car nut that religiously changed the oil in an original engine and they are pretty clean inside or someone did a rebuild/replacement along the way and these engines are still usable for drivers/cruisers.

    Good Luck!
  3. brownbomber

    brownbomber Silver Level contributor

    Thanks! I'm taking your advice I like the idea of lifters,pushrods,rockers and call it a day that's what I'm going to try,I'll keep ya posted. I think I might sell her and buy a gs that's gone through and done. if anyone selling or trade I'm open for offers!! thanks gsgnut!
  4. Mark Demko

    Mark Demko Well-Known Member

    Honestly, If I were in your shoes, I think I'd buy a finished GS also, IF you can afford it. It sounds like you dont have much experiance with mechanicals, so that sounds like your best option, BUT, there again, you'll be spending MUCH more than 1500 bucks, probably around 8 to 18 grand for a 350 GS, and more for a 455 car, and even more for a 455 Stage 1
  5. brownbomber

    brownbomber Silver Level contributor

    Thanks Mark I hear ya, a finished GS would be great but I got to deal with this girl first. I have a lot of mechanical exp, 30years, 20years with Nissan motor corp, its Multiple Sclerosis that holds me down, limits me to what I can do but I still try as best I can... I'm really slow but very picky about her outcome. Well anyways cam is out, 3 flat lobes, cam bearings look amazingly good, I'll replace the front bearing only (not pulling motor)comp cam 268h comp, TA rocker assem, TA pushrods, comp cam springs and seals and lifters (OPGI had a summer end sale) TA oil pump booster plate and pressure reg, TA cover, TA water pump, TA intake, this should freshener her up a bit, I have all parts just a very slow process, timing cover only one broken bolt but to much electrolysis. I'm ready for all new parts to be installed will see how it goes, need to find someone with a cam degree kit....were havin fun!!!

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