Help me choose cam/rocker combo..

Look Its Aaron

Your car looks like it came straight from Mexico.
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Nov 18, 2001
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Fontana, Cali
I am going to be putting on some GT40 irons on my car, and I would like to know what cam/rocker combo you guys reccomend for this combo.

Also with what you tell me, what life will I be looking at. At what lift do the gt40 heads not flow anymore?

Later on down the line I will probably be using a GT40 tubular or Edelbrock performer.
 
Assuming your GT heads are not ported: Are you running a stock intake? (you left that part out)To take full advantage of the heads you will need to add at least a ported stocker. A cobra intake would be the next in line.

So many variables on the cam.... For a street car, I would probably run TFS1. But that is just me. Some people will recommend a comp cams variant, others still will say go custom. If you want a good street car, don't go too big...

For rockers, this also depends on the cam. Get some RR's for sure, but if the cam you choose has high lift numbers settle for some 1.6's. Then again, if your cam has lower lift numbers spring for some 1.7's to compensate.

I don't know how much I helped you.... But the choice is really up to you. Just make sure you build for how you will use the car. Too much on the street isn't very fun (I Know)
 
Havent put it all together yet, but the parts I have gathered so far are:

TMoss ported lower
Lunati 51014 218/226 500/510 112lsa
Stock GT40 Irons
65mm TB
C&L 76mm MAF.

Think Im gonna stick with 1.6 rr's as opposed to 1.7's because the spring package I put on the heads are only good to .550 lift. The 1.7's would move the lift up from 500/510 to 531/541. I think that is too close to the max lift of the springs.

Mines an AOD vert with 4.10's and a 2800 stall. I think it will work pretty well. Its 95% street car.
 
Crane 2031 and 1.7's....very smooth HP and TQ curves and it will still put up good numbers. Power will be over by 5600-5800 and that is just about where your combo will stop flowing anyways....
 
Rick 91GT said:
Crane 2031 and 1.7's....very smooth HP and TQ curves and it will still put up good numbers. Power will be over by 5600-5800 and that is just about where your combo will stop flowing anyways....


How does the 2031 sound? is it agressive? that kit also comes with valve springs right?
 
Rick 91GT said:
Crane 2031 and 1.7's....very smooth HP and TQ curves and it will still put up good numbers. Power will be over by 5600-5800 and that is just about where your combo will stop flowing anyways....



the 2031 is almost the same as the e cam right? the reason i ask i only went to the track one time with the h/c and im not sure of my shift point. gears play a part in this right? i have stock gears, it seemed like i had betters times and mph shifting earlier ( 5000 ) and getting into fourth gear before crossing the line. i never went past 5500 either. sorry to hijack, but what do you think, should i be shifting in the higher rpms?
 
really depends on your combo (what heads, intake with that 2031) if its more like the trickflow street or 5.0 then 5500 - 6000 should be good, if its more like the r series, then more around 6500 or 7000 should be good IMO

you powerband thats shared between your intake, heads, and cam, also paired with your exhaust setup, should really determine where you shift at

in other words, keep the rpms in your powerband throughout the most part of the pass, if youve got a torque monster that makes no power above 4500, it doesn't make sense to wait till 6k to shift now does it
 
The 2031 will not carry power past 6000rpms.....no matter what head or intake you are running. The cam has a small lope but really works well with the factory EEC, it is also very smooth and can cruise in higher gears at low rpm with out bucking. We upgraded seals and springs seperate... I have all the specs if your interested. Crane gave the 2031 a new number you can find it on their site.

It is very different then an E-cam, the E is a Crane 2040.
 
oh... i was just kidding anyway hehe


didnt really know what a 2031 cam was equal to, just letting legalize know that it depends on his combo of where to shift at

ill keep my mouth shut from now on haha
 
Rick 91GT said:
Crane 2031 and 1.7's....very smooth HP and TQ curves and it will still put up good numbers. Power will be over by 5600-5800 and that is just about where your combo will stop flowing anyways....

Ditto that.

I got mine thinking I was going to get iron GT-40s and I needed a smog cam(when I had my '89 GT). Low and behold I got a job and some Edelbrocks. It will cruise along at 1500rpm/55mph with a T5 and 2.73s, but it wants more gear than that. It was a pain trying to do 10mph in parking lots. I was going to get 3.55s, but sold the car before I went that far. I used the '93 Cobra roller rockers(also a Crane part).

Its going to be worse with the current 4-speed and 3.00s...but damn the non-smog engine is fast :D.