I want the rough idle but dont want to have to buy new springs, lifters! I will get a small stall eventually but moneys REAL tight around here now! I just want your opinions on what cam I should look into!! Thanks in advance!!o No:
You HAVE to run new lifters with a new cam. I dont believe a 268 cam will give you a rough idle, maybe a bit of lope, but not fender shaking idle. Also, new springs are recomended with any new cam, if only because the old ones are probably soft. If I remember the '75 heads have high exhaust guides, so your going to have to check for retainer to guide clearance with ANY cam that has increased lift over the stock lift of .398 (I think thats what the stock exh. lift was)
X2. If your not going to get new springs and lifters dont even bother getting a new cam. Why? You dont want to do this only to collapse an old lifter and end up with an engine miss or worse. The old springs may not have enough tension to close the valve in time since the new cam has more lift and duration, and the valve could hit a piston. There are many things that can go wrong, having the springs match the cam is important. Especially if they are old / have alot of miles on them. What compression are you running? 9.0:1? The higher compression pistons have a shallower dish, the low comp pistons a deeper one. This will help determine what cam you can run, because once you get so big you will need pistons with valve reliefs.
I think you would like the TA 212 cam better than the 268 cam. I had 268H cam in my 350 and this was way back in 1984. The cam had a good lope to it. But it would take to about 3000rpm for the car to get going. But at the time I had a stock convertor in it and 268 rear gears. With a 373 gear I ran 14.89 with it. A lot of people here seem to like the 212 cam as a good jump up from the stock cam. The 268H cam is a very old design and I just think that there are better ones out there now. Check out the Crower site and Lunati site out for their cams as they have newer style cams for the 350. There was another cam from TA that I thought might be a good cam it had a 118 LC with some good lift and duration numbers and with the 118 LC it probably would have some real good low end torque.
I have new lifters, springs! I am just assuming my compression is 8:1 I bought the motor like it is!!!
Since you have such low compression the 290 would be a bit much of a cam... The TA 212 cam would work fine with the low compression,I have done this before. Later if you have more $ then you could consider either adding high compression pistons, or milling the heads to up the compression to go with a larger cam. keep in mind that if you like to run regular grade fuel then you are better to stay with the low compression. If you do not mind paying for premium fuel then up the comp. and go with a large cam. Also keep in mind that a large cam with lots of overlap (which gives the lope) will work best paired with a trans. torque converter that stalls at 2500 or more... Same goes for rear end gears, large cams work best with a 3.23-4.11 gear.
You have to ask yourself "do I want an engine that sounds nasty but runds like a turd, or an engine that sounds smooth and runs well"?. If you want a combo that can perform as well as it sounds you'll need a higher compression ratio and heads that can handle an increase in intake and exhaust flow. Devon
The 212 has a pretty smooth idle, better than stock though. If you want a lumpy sound go with a true dual exhaust no crossover or x pipe. The Lunati 67003: http://www.youtube.com/watch?v=m2hrXV0hjTg&feature=related Crower #50529 here: http://www.youtube.com/watch?v=wuo7C-wjoIE&feature=related
WILL IT IMPROVE OR MAKE IT WORSE? i HAVE THE 75 .3O OVER & i ALSO HAVE 71 350 HEADS! WHAT IF I PUT THE 71 HEADS ON THE 75 MOTOR? YES OR NO? MORE COMPRESSION?
Same compression between both heads on the same block with the same pistons. Compression difference came with piston changes between blocks and different years.
You could mill the heads to gain compression however first you would want to measure the head CC, the piston dish, depth of piston below deck height ect. Never try to change the compression ratio without knowing what you have to start with. You say money is very tight so I would advise against getting into all this untill you have the extra cash to do things right the first time. Like Devon says if you want a big cam, you also want the compression to make it work and premium fuel goes allong with that. If you want to get an idea of the condition of the engine I suggest completing a compression test as well as a leakdown test. If you have compression readings of over 190 then who knows you may have higher compression than you think. No use adding a new cam if the engine is in poor shape, there may be more important things to address.
Its all apart for inspection! I think I will go with comp 268H or TA212! A small stall & shift kit for the turbo 350!!
I bought the entire comp cam kit, pretty hard to beat the price. Sure there is always a better cam by somebody else. If money is that tight and price is the deciding factor then the comp cam should fill you needs, I think I paid like 284.00 from autozone. Cam, litters, springs, timing chain, lube.
I have givin this alot of thought! Whatched alot of you tube vids & I think I like the sound of the lope at idle better (less $ too)! Thank you guys for all your knowlege keep it coming! I know I will have ALOT more questions before I am done!!:TU: :3gears:
