So if I go that direction what would be a mild cam that will still work with the stock TBI? Or at least with minimal mods. I have to look at it but it's priced at $50!!!! 030 over and was destined for a race car but did not have provisions for a mechanical fuel pump which was a requirement in that particular class.
It was a GOOD stock cam in 1982 (the first year for the L69 305 HO carbureted motor), just as good in 1992 (the last year for the TPI engine) and still good in 1997 (the last year for the LT1).I may have a deal on a block with a near new rotating assembly, flat top pistons and rods. The succeeding engine families were each only mild incremental improvements over the previous engines in terms of cam design. Of course, the TPI (L98) cam had virtually identical lift to the old flat tappet cam (it was a roller cam clone of the original flat tappet design), while the LT1 cam had considerably more peak lift but still nearly identical duration and LSA. The duration and LSA remained very close to those specs over the years despite the fact that they were turned into roller cams and put in EFI engines. Or break out the degree wheel and dial gague and measure for yourself.īoth the LT1 (F-body version only- not the Caprice version of the LT1) and the earlier TPI roller cams all decended from the old 305 L69 HO engine's flat tappet cam from the early 80s. You pretty much have to accept that GM did a lot of work making them right for mild/stock motors and stop asking so many questions. In short, getting true specs on a factory cam is a big 'ol mess. For instance, a factory-installed chain might drop you in right around 115-117* ICL (truly straight up) while an aftermarket chain set at 0* drops you in around 112* (~4* advanced). The old engines seem to have chain sets that can be about 4* retarded from what an aftermarket chain would give you on the same cam. Many factory engines have timing chains with different TDC indexing than a common aftermarket chain set. ICL (how advanced or retarded it is) is a different story. Somewhere in the range of 115-117* LSA is often quoted and nobody argues with it. 050 duration specs seem plausible, but the LSA and ICL (advance/retard) vary depending on whose specs you believe.
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