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I had the stage 1 cam and 1.7's in 2 1988 cars with stock pistons and had no p/v problems... but as everyone will tell you- check it first. I had gt40 iron heads on both cars.
 

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Discussion Starter #3
i just have stock heads on it to i forgot to put that on there. one more question. how about running 1.7's and a b-cam i know it adds to the lift but do you change your shift points at all or do i still need to shift at 5100. any of you guys run this kind of setup before?i really need some advice so any would be a big help.thanks
 

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Discussion Starter #6
i just cant make up my mind. does anyone know if i will be shifting any higher rpms if i add 1.7's to a b cam?
 

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I guess the shift point might be up a little than with smaller rockers........But you won't be shifting at 5100 rpm! Thats way too low........I mean I shift at 5200 rpm on my stock motor for gods sake. Sure the power might end at 5100 with the b-cam (i'm not sure) but that doesn't mean you shift there or you will be way out of your power band in the next gear.
 

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What's the rest of your set up? Intake? Heads? Exhaust? Hard to help you with shift points when we don't know anything about what else you're running. When you say stock set up, do you mean everything stock except the cam and rockers, or just a stock bottom end?

First, without the recommended heads/intake/exhaust mods to go with either cam you've mentioned, they're not going to perform very well. They'll likely kill your bottom end for little if any gain on top. Second, the 1.7 rockers will increase lift close to the .500" range which is too much for the stock springs. Chances are good you're going to have valve float before 5200 rpm with those cams and 1.7's anyway especially if the springs have some miles on them. Third, peak lift has nothing to do with p to v clearance - at peak lift the pistons are way down the cylinder. It's duration and overlap - specifically earlier opening intake valves and later closing exhaust valves that cause clearance to decrease. You have to measure to be sure as no 2 combos are alike. However, if you're thinking about adding either of those cams to an otherwise stock engine, you'll likely be disappointed with the outcome.
 

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Discussion Starter #10 (Edited)
i have stock heads and bottom end but it is carbed with msd,x-pipe,headers,gears,eldebrock rpm intake that pulls to 6500,i already have a b cam and its still pulling hard at 5100 with stock rockers with no valve float with stock springs it only has 70,000 miles on the motor.the car ran a 12.70 spining a brand new set of hoosier slicks it is very a very strong running car.i was just wondering if i would be changing my shift points with the added lift?the b cam duration is [email protected] and the rockers wont change that so i should be ok i had a friend that run them with no problems at all.i have new set of crane valve springs going on that can hold .560 lift
 

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Ran my b with 1.6's intake and 1.72's exhaust. Depending on track conditions and weather, I launched between 6000 and 6500. Shifts were usually around 6200 or so. That was just my combo. It took alot of playing/ tuning to figure it out, and I had TW heads.
 

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I am running stock heads with tfs cam and 1.6 roller rockers.
I suprisingly didn't lose much bottom end. I listened to everybody about not going with a tfs cam, and was expecting a big difference in bottom end and I found very little. Sure there is some but in my opinion i think everybody over exaggerates. But hey maybe I just got lucky on my set up.
 

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Unless someone else has an identical combo (intake, exhaust, gears, tires, suspension, tranny, everything), their shift points may not work for your combo. Why don't you just experiment at the track and see what produces the best times? Or dyno it - then you'll know where your power peak is and you can determine shift points from there. As mentioned before, if your heads are stock, with the 1.7's there's a good chance that valve float will set your shift points for you - and you'll know it when you feel it.
 

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Discussion Starter #17
what im really asking i guess is do the 1.7's change the shiftpoints because of the extra lift? like i said i have a set of crane springs to hold the extra lift.i know im not the only one who has run a b cam with a stock setup and was just wanting to get some kind of idea where to start to shift the car and then work from there.my race track close to the house is usually full so its hard to test it out alot.
 

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Sorry - forgot about the Crane springs - my bad. The 1.7's won't make that much of a difference - start where you were shifting before and experiment from there.
 

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Discussion Starter #19
one more question.i know the b cam says peek horsepower at 5100 but is that with inj. or the same for carb as well. the ford cams dont really explain themselves very well.i know the motor is getting more air with the carb instead of inj. but didnt know if that would change anything because of the added air and fuel from the carb
 

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Those advertised power peak numbers are pretty meaningless - your set up is likely different than what they used to rate the cam in terms of intake, heads, exhaust, etc. I just checked their catalog - they don't mention what components their power peak came from. That info is really not helpful in your situation - my opinion. Drive your car. Get a sense for when it stops pulling. When you can, find a dyno day and have it dyno'd - that'll tell you what the power peak is. Actual racing times are about the only way to know for sure if your shift points are helping or hurting your acceleration rate. Any approach other than that is pretty much just guessing.
 
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