my car is getting a whole new breath of life as its getting the engine rebuilt and a bunch of mods done. i wanted to see with you all to hear what you had to say about the size of cam i should get. i want something that sounds really mean! so what do u think?

 

Who is doing the rebuilding, what mods are being done and how much is it costing? Depending on the cost and warranty [or lack of one], a crate engine is often a more cost-effective option.

At attractive as it sounds, hot-rod 'lumpy idle' camshafts don't work well for most street cars, and especially for TPI ones. The gas mileage will suck and after a while you'll hate to drive the car except on special occasions. Some people like the GM high performance camshafts, such as ZZ3, ZZ4 or an LT4 "hot cam" grind. An easier alternative to installing a camshaft that you might hate later on is to upgrade to 1.6 roller rockers and new valve springs. If it was my car, I'd go for the Vortec iron heads and TPI intake manifold from Scroggins-Dickey, and not mess with the stock 91-92 TPI 350 camshaft. That way I'd have much more power derived from better efficiency -- and not a gas hog with poor street manners.

Please read this excellent Camshaft article on TGO --
https://www.thirdgen.org/newdesign/tech/mods3.shtml

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TPI Late-Model Builder's Guide [Car Craft] -- A good way to gain the benefits of more valve lift without actually digging into the engine is to install a set of higher-ratio rocker arms. Most Chevy small-blocks, including TPI versions, use 1.5:1 rockers, so by adding an aftermarket set with a 1.6:1 ratio (preferably full roller rockers), we effectively increase the cam lift. The only caveat here is that you'll probably need a new set of valvesprings. If your TPI engine is relatively new (unlikely at this point in time), you might be able to skip this step,

Even the hottest factory TPI cam is pretty tame, but avoid the temptation to stick a big, lumpy stick in its place, as the electronic engine management won't like it, particularly on cars with speed-density-type induction metering. Many cam manufacturers offer grinds specifically for TPI engines, and factory roller-cam versions can also use grinds intended for the later Gen II LT1 and LT4 engines. For a project like this, the net valve lift should probably hover on the low side of 0.500 inch, while the duration at 0.050 should be somewhere from 210-220 degrees. The lobe separation angle should not be narrower than 112 degrees, as excessive overlap will have an adverse effect on idle quality. A cam swap like this can be worth as much as 25-30 hp and three tenths.

The iron heads used on TPI 350s aren't bad when compared to most other iron GM heads of the time, but by today's standards, they're weak. In fact, the Corvette aluminum heads of the same period, which were a popular upgrade, are also not very impressive today. For a relatively low-buck head upgrade, GM's Vortec heads offer excellent bang for the buck, and Scoggin-Dickey offers a lower manifold to mate them with the TPI intake. But, if you already have a performance lower intake, a set of aftermarket aluminum heads, such as those offered by Edelbrock, Air Flow Research, Trick Flow, and others, will boost output significantly. We actually haven't tested this step with modern aluminum heads, but a 40hp gain is not out of the question.
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Stock cam summary --

Generally, most LB9 automatics had the "LA" (LameAss} cam, or "peanut" cam as some call it. All LB9s with automatics from '86 through '89 had the LA cam (P/N 10088155), and most '90-'92 305 equipped with automatic transmissions had the same cam. The design changed from a flat-tappet in '86 to a roller-type in '87, but the grind specifications were virtually identical (.350/.384 - 179/194 - 109.0). A few 305 automatics got an improved cam (.383/.404 - 191/202 - 112 ) , but most of those were B4C cars with LM1 engines, not LB9s. These were designed as SEO police vehicles, but some of those got out of that duty and into the general population.

'87-'92 LB(s with a 5-speed manual (T5) transmission got an impreoved cam grind (P/N 14093643, 10066049, or 10111773) which was even better than the B4C/LM1 cam grind. This same camshaft was stock in 350 automatics during those same years. These vehicles are easily identifyable by the tachometer red-line range. The red-line for a LA cam is 5,000 RPM, while the better cam offers 5,500 RPM.

The '88 and '89 305s and 350s had arguably the best factory can grind (.415/.430 - 207/213 - 117.0), with the highest lift, longest duration, and LSA of any of the breed until the LT1 was introduced. Speed-density schemes necessitated a reduction in lift and duration, and especially LSA (.413/.428 - 202/207 - 114.5), apparently to enable the ECM to tolerate the idle vacuum. MAF cars were a bit more immune to idle vacuum since the MAF could meter air accurately at any pressure differential.
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ok, so the transplant has begun. apparently my engine was really messed up. rods were bent and the cam is burnt up and anything on the right side of the block is completely covered in oil. anyways, im polishing the **** outta the intake manifold and heads as well w/ a little porting on the exhaust ports. roller rockers and a roller cam are on their way. also adding a fluidampr and aluminum pulleys. also gettin a TCI trans. there are other things also but i dont have all day. the car should be pretty sick when done with everything in about a month. my goal is w/in the 12 sec bracket. i'll keep u all posted though, then i'll finally be able to go to the track and meet some of you all! lata