1158

After completing my build I was having problems with over revving so I decided it would be wise to go ahead and replace the valve springs. Because the cams need to come out to do this, I decided to replace the cams as well. This is in a stock GSR with a SC34 (t3/t4 57 trim) with .63 A/R pushing out 9 psi. The full setup is in the link in the sig.

Here is the GSR cam plot


And here is the CTR cam plot


The dyno runs were not done on the same day, but as luck would have it temps/rh were very close to being the same on each day.

The overall gain was not as high as I had hoped 9hp 1tq, but I feel the car has more power thru the entire rpm band and feels more responsive. The turbo also hits full boost between 300 and 500 rpm earlier. Depending on the conditions I have full boost around 3500 rpm.

As a side project I used my IR temp gun to see what kind of temps I was getting on the manifold as each pull was ending. At the center of the collector the highest temps I could find were between 500 and 550 F. The runners would range between 350 and 400 F. Temps were also very quick to drop...falling to around 300 no more than 10 or 15 seconds after a pull. So I think the coating is doing it's job. I understand there would be more heat generated during hot lapping vs on a dyno, but I wouldn't expect more than another 200 F at most.

1fastEK9

''CTR'' cams are better, what kind of program are you using 2 tune your car, me and my brother put a turbo set up on a stock B16 and gain 321hp at the wheels with a t3t4 sc61 stage 5, using hondata, back in the days, GOOD LUCK

boostfeen

..CTR

1158

Using Power FC for EM. I agree that the CTR cams are better. The dyno didn't show much of a gain, but the engine has more response and makes boost quicker. At higher boost levels I'm sure I would see even more increase.

1158

Does anyone know if the CTR low rpm lobe is different from the GSR? I would think they would be the same, but it doesn't feel that way.

Boosted2K

Does anybody have any experiece with swapping GSR's for CTR's at higher boost and horsepower levels.

This was going to one of my next purchases. What kind of gains at around 25psi on a GT35R could be expected? Higer I hope

0xenocron

Besides swapping the cams, did you actually manipulate the fuel/timing maps?

The only reason your peak HP is higher in the second graph is because you revved higher...your curves are very similar.

swappedcx

am i missing something then because I see 258 @ 7800rpm then 267 @ 7800rpm

1fastEK9

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by swappedcx &raquo;</TD></TR><TR><TD CLASS="quote">am i missing something then because I see 258 @ 7800rpm then 267 @ 7800rpm</TD></TR></TABLE>


how about your fuel are you using 91 or 100 octane,and what size of injectors are you running? how about your fuel pump? it sounds like this is your problem, the motor is way more stronger than that, on a stock GSR we got 345 hp at the wheels with 10 pounds of boost

White Smoke

What all did you do to the tune? You are using cam gears right? What were the settings? If your not using gears then you just wasted ~300 bucks on those cams as minimal gains are to be expected at the stock setting.

1158

I'll try to answer all the questions.

First, this is on 93 and the maps were retuned for the cams. Cam gears were also adjusted. I forget what setting they are at. The graphs are misleading because the x axis labeling is different between the two. Both runs were reved to right around 8200.

As far as wasting money, the reason I was in there was to replace the stock valve springs with Toda's because the revs were coming up so quick I was worried about valve float. Since the cams have to come out to do the springs might as well put something better in there.

I'm using 750cc injectors, Walbro pump. Remember, this is a Mustang Dyno...probably closer to 310 on a dynojet. I'm hoping to throw the car on a dynojet in the next few weeks.

1158

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1fastEK9 &raquo;</TD></TR><TR><TD CLASS="quote">on a stock GSR we got 345 hp at the wheels with 10 pounds of boost</TD></TR></TABLE>

What turbo were you using and what dyno?

tony1

At those kinds of power levels i wouldn't expect big gains from those cams.

SOUNDEFFECTS

I agree with Tony1, its relative to the % increase of the power you had with the GSR's. Plus when you start getting into higher boost levels where scavenging can take plus, the CTR cams will start to show bigger HP gains and bigger % gains over the GSR's because of the duration and lift differences.

Still not a huge difference like adding in some Skunk2 pro stage 2's vs GSR's, you would see a bigger gain there as well.

95GSRTT

Thats either one hell of a messed up mustang dyno or one hell of a messed up dynojet you would be going to if you showed more than 40 hp from switching.

1158

Yeah, I figured I wouldn't get much gain because I'm not flowing a lot of air. At some point in the future I'll need to build the engine at which point the CTR cams would provide more benefit when I crank up the boost.

I'm just trying to figure out why I'm building boost quicker. Are the low cam lobes different between the GSR/CTR?

75w90

wouldn't the ctr have a more of a over lap than the gsr?

1158

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 75w90 &raquo;</TD></TR><TR><TD CLASS="quote">wouldn't the ctr have a more of a over lap than the gsr?</TD></TR></TABLE>

Yeah, it has more on the high rpm lobes, but I'm not sure about the low rpm lobes. My crossover is set at 4500 and I'm making 9 psi around 3500, before the switch I was making 9 psi around 4000. I'm not complaining, just trying to figure out why. I haven't chnged anything other than the cams and the valve springs.

IntegraTypeR

iTrader: (1)

am guessing that on the CTR run you advanced the intake and retarded the exhaust cams? am trying to say you moved the cams effienciency more into the mid range where you see it build more boost earlier! does that make sense?

you should have started with 0,0 ...reach your hp goal as you increase the boost (after tunning) then play with the cam gears to see any torque improvement around your band!

SOHC_MShue

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1fastEK9 &raquo;</TD></TR><TR><TD CLASS="quote">how about your fuel are you using 91 or 100 octane,and what size of injectors are you running? how about your fuel pump? it sounds like this is your problem, the motor is way more stronger than that, on a stock GSR we got 345 hp at the wheels with 10 pounds of boost</TD></TR></TABLE>
Dude chill his power isn't bad. Should be close to 310 like he said on a dynojet. You cant go comparing your motor that was dynoed on a different dyno with a completely different setup to his setup. 10psi on his turbo isn't the same as say 10 psi on a sc61.

1158

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SOHC_MShue &raquo;</TD></TR><TR><TD CLASS="quote">
Dude chill his power isn't bad. Should be close to 310 like he said on a dynojet. You cant go comparing your motor that was dynoed on a different dyno with a completely different setup to his setup. 10psi on his turbo isn't the same as say 10 psi on a sc61. </TD></TR></TABLE>

I agree 100%, I wanna know what turbo was being used for the 345 at 10psi. This is also a conservative tune. Which is what I asked my tuner for. I want the car to drive good, make power, but last.

1158

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IntegraTypeR &raquo;</TD></TR><TR><TD CLASS="quote">am guessing that on the CTR run you advanced the intake and retarded the exhaust cams? am trying to say you moved the cams effienciency more into the mid range where you see it build more boost earlier! does that make sense?

you should have started with 0,0 ...reach your hp goal as you increase the boost (after tunning) then play with the cam gears to see any torque improvement around your band!</TD></TR></TABLE>

You know what, I bet you are right. When the car was initially tuned, we ran out of time and couldn't play with the gears. I bet just changing the gears helped with spool time. That makes the most sense. Thanks!

Heylookits shawn

hrm, i have ctr's on my turbo b16, and i made 247hp and 165tq on 10 lbs. do you think getting cam gears would decrease my spool time? because im im not making full boost till around 5k. it is a pretty large turbo though

95GSRTT

You also have a b16, which I believe he does not, which will make a difference in spool times.

Heylookits shawn

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 95GSRTT &raquo;</TD></TR><TR><TD CLASS="quote">You also have a b16, which I believe he does not, which will make a difference in spool times.</TD></TR></TABLE>

yea i know, the difference in displacement equates to a difference in spool time, but he said after changing his cam gears he reduced spool time a few hundred rpm, something this tq-less monster could use