You might want to start a new thread given the age of this one.
But my answer is it depends on the goals. Plenty of people have hit 700+ on stock cams. Unless you want the lope or are looking for every last horsepower I'd stay with the stock cams.
What's the best cams for 03 terminator
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You might want to start a new thread given the age of this one.
But my answer is it depends on the goals. Plenty of people have hit 700+ on stock cams. Unless you want the lope or are looking for every last horsepower I'd stay with the stock cams.
do cams if you have the heads open.
As per the op’s question from 7 years, probably a stage 2 blower cams from comp or MMR (quartet.) You can’t get much accuracy above 7000rpm with the stock ecu, so it doesn’t make sense to rev to 7500rpm without a stand alone.
Upgrading to a wider/larger lope cam opens your valves for a wider portion of the combustion and exhaust cycles.
this is a no brainer for extra power.
I’ve seen stock port Eaton cars on 13p-15psi with full bolt ons pick up 30-40whp and drop 2-3psi with ported heads and a well sized cam/properly degreeing them.
you can go from 430-450whp to 470-490whp with head/cam work on a stock Eaton.
it’ll drop boost because you’re going to be reducing the the restriction on the motor. Boost isn’t the end all be all. You’ll effectively be supplying the same cfm of air that the Eaton is pullied for as before which is all that matters. The boost will drop because your combustion and exhaust “chamber” will in effect be slightly more cavernous for slightly longer durations of the intake and exhaust cam rotations since the valves will be open slightly longer.
comparatively putting a narrower cam quartet in the head would increase boost but not add any horsepower. You would lose horse power and torque and create excessive back pressure. Make sense? The valves would be closed longer.
I make 810whp on 10-11psi with turbos on a 5.3L at 9.3:1 compression with very ported heads, stage 3 turbo cams custom ground to my build etc. very free flowing mill, rev happy and reasonably torquey for a ported head turbo car.
I went with MMR cams.
for a blower car, you want a lot of intake to feed the blower lobes.
On a turbo car you want to help spool so you can often run a smaller intake cam and a larger exaust cam to get the air out.
speak with a cam expert to help explain your goals, what you have now and plan to have later, and spec a great cam.
Good luck, best wishes
Cams are a great mod but unfortunately very expensive in the 4-cam Mod Motor.
I have 2 sets of new unused ‘13-14 GT500 cams that are the same as ‘05-06 GT supercar cams.
My brother is going to be rebuilding his turbo Terminator and I figured the GT cams and springs would be a nice mild upgrade.
A turbo car is a bit different but be careful on cams and over camming a small 4.6 motor.
Boost, compression and cams together if possible, otherwise in that order.
-J
I have 2 sets of new unused ‘13-14 GT500 cams that are the same as ‘05-06 GT supercar cams.
My brother is going to be rebuilding his turbo Terminator and I figured the GT cams and springs would be a nice mild upgrade.
A turbo car is a bit different but be careful on cams and over camming a small 4.6 motor.
Boost, compression and cams together if possible, otherwise in that order.
-J
On a stock ecu street car terminator running full or near full weight and obviously capped to 7000rpm, maybe 7250rpm (ecu accuracy), a stage 2 cam for 2000-7000rpm or 2250-7250rpm is the most you can realistically justify.
more you open up the valve timing, more you open up high rpm performance ha low rpm performance.
lower rpm needs an ample amount of time to fully combust. If you open the valves too soon, (or leave them open too long basically), the combustion is less complete, the explosion is smaller, and the power generated is less.
you’re essentially letting the flame experience some wind which is blowing it out, much like a lighter on a windy day outside. How much so is dependent on how much rpm, and the given mill’s geometry.
putting a race cam or race intake on a street car is going to be terrible for drivability, just as putting a 106mm turbo on a 3L is. Sure it’s great once the engine (air pump) is up to speed, but it makes getting up to speed take much longer.
flooding a motor with air or fuel will make it very lazy. Leaning it out will and running optimum air flow with the lesser amount of fuel safely needed and no more will yield great results.
On a 4.6 8.5:1 terminator Eaton blower car, a gt500 cam quartet from 2013/14 is probably a hair big as they're designed for the 5.4-5.8L combustion chambers and head architecture.
I think it’s less expensive to do a 2013 gt500 cam, sure, but there are probably better specced cams for 7000-7250rpm on a 4.6 terminator mill with stock c heads or mild c heads.
get a spec card for a proper stage 2 comp cam or crower cam or off the shelf MMR blower cam in that rpm range for a 4.6 Eaton blower terminator and compare it to the spec card on the gt cams.
if they are very similar in the important areas then save the cash and pick those up but if not, it could make the engine laggier and want for 7500-8000rpm of airflow (or whereever a 4.6 8.5:1 Eaton at 15psi might have the same cfm airflow of a 5.4 or 5.8 gt500 mill at 6500-7000rpm)
The point is you want to spec cams that match the airflow needed to optimize what you are working with.
good luck
more you open up the valve timing, more you open up high rpm performance ha low rpm performance.
lower rpm needs an ample amount of time to fully combust. If you open the valves too soon, (or leave them open too long basically), the combustion is less complete, the explosion is smaller, and the power generated is less.
you’re essentially letting the flame experience some wind which is blowing it out, much like a lighter on a windy day outside. How much so is dependent on how much rpm, and the given mill’s geometry.
putting a race cam or race intake on a street car is going to be terrible for drivability, just as putting a 106mm turbo on a 3L is. Sure it’s great once the engine (air pump) is up to speed, but it makes getting up to speed take much longer.
flooding a motor with air or fuel will make it very lazy. Leaning it out will and running optimum air flow with the lesser amount of fuel safely needed and no more will yield great results.
On a 4.6 8.5:1 terminator Eaton blower car, a gt500 cam quartet from 2013/14 is probably a hair big as they're designed for the 5.4-5.8L combustion chambers and head architecture.
I think it’s less expensive to do a 2013 gt500 cam, sure, but there are probably better specced cams for 7000-7250rpm on a 4.6 terminator mill with stock c heads or mild c heads.
get a spec card for a proper stage 2 comp cam or crower cam or off the shelf MMR blower cam in that rpm range for a 4.6 Eaton blower terminator and compare it to the spec card on the gt cams.
if they are very similar in the important areas then save the cash and pick those up but if not, it could make the engine laggier and want for 7500-8000rpm of airflow (or whereever a 4.6 8.5:1 Eaton at 15psi might have the same cfm airflow of a 5.4 or 5.8 gt500 mill at 6500-7000rpm)
The point is you want to spec cams that match the airflow needed to optimize what you are working with.
good luck
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