Hello there, Next Month I will be doing a engine build-up to replace my 305, Im basically going to build a roller 350, use my TPI set up stock injectors for now but will use a APFR, Use my chip. I am debating on 2 cams from Comp, They are the Extreme Energy HR Cams, I previously Had a XE274H in my carbed 350 in my Monte Carlo SS, Was happy with it and sounded awesome!

For the 350 TPI I was debating on the following:

PN# 08-502-8 XR269HR-12

269in/276ex dur @ .6 tappet lift
218in/224ex dur. @ 0.05
.495" in .503"ex lift
112 LSA
general RPM 1500 to 5500
This ca, basically states good for a 305-350TPI with chip and upgraded exhaust, basically what I have now. Will there be much difference between this one or the larger cam below?

The other is the next series up,
PN#08-503-8

276in/281ex dur @ .6 tappetlift
224in/230ex dur @ 0.05
.503"in .510"ex lift
112LSA
general RPM 1800 to 5800
This cam recomends a chip, injectors, plenum, runners, exhaust, and a 2000 stall, now the deal is I will do these at a slow pace but will this cam still work without problems esp with the stock converter? I plan on doing the runners as well later on, and going to dual 2.5 exhaust.


How do you think the car would Idle and the exhaust sound, I know the 274 Cam in the carbed 350 sounded good.

All help appreciated.

 

go with the big one

 

You do know the injectors on the LB9 TPI's were a bit smaller than the ones on the L98 TPI's right? 19# vs 22#. I'm not 100% certain but those 19#'ers might hold you back. I'm guessing the chip will be the LB9 chip? I'm not sure about that one either ...

 

Go with the smaller cam if you plan to stay with a LTR setup. Step up to the bigger one if you're final plans include a Super Ram, Mini-Ram, or Stealth Ram.

 

You will have trouble staying with your factory chip. You will need a custom program. Best by far is to have someone program your car. Next best is a mail order custom to your car by giving them the parameters of your installation.

Next question. Are you running the stock heads? With the horsepower potential of those cams you need to step up to 24 pound injectors. My vote would be for the smaller cam of the two. Also if you are going to run the stock heads make sure they will handle the lift of the cam. Might give Comp Cams a call.

 

I would actually recommend going to 30 lb injectors with the bigger cam (which I have). The 24 lb injectors are going to be static at WOT with that cam.
If you go with the smaller cam, the 24 lb'ers might suffice.

 

Doing some searching, found that a stealth ram isnt bad on price, so I was now considering a stealth-ram and possibly a hot-cam if the extreme energy's arent a good choice

 

Nobody asked yet, but what heads will you be using?
If stock heads then I'd stay with the smaller of the cams.
I would change heads before swapping to a HSR because they are the bigger restriction.

 

I ran the first one with my stock 350 bottom, TF heads , stock injectors and superram. Also ran this on the stock 89 Prom and stock converter. Ran ran good and got good MPG too lol. Also passed e-check with just converter and EGR