The Camshaft Mega-Thread!

[idahotuner]

yeah i swore i would build a 400 stock block sr. did that, then it moved into a built over bored block, with a gt2871r now its moving to a top mount. so i am sure solid lifters will be somewhere in the evolution.

[PyR0NiAk]

That sounds familiar.. VERY familiar.

[idahotuner]

would have been alot cheaper for me to do it all at once, but no, i am stubborn and thought i would be happy with one setup. but its been a fun trip so far.

[maverick06xx]

Alright so i'm thinking the 63 ar gt3076r will support atleast 500whp right on pump gas?

isis intake mani port matched
peak boost kit manifold port match
1mm oversized supertech intake valves nitride
1mm oversized supertech exh valves inconnel
brian crower valve springs and retainers
brian crower 272/272 cams
3-5 angel valve job
ported and polished
running greddy ultimate emange

I just want to hit 500whp thats it no more thats max...the turbo i have atm is a AGP turbonetics delta 48 with the 63 ar but not sure what this turbo will net me...

[idahotuner]

you wont do it on pump gas i can tell you that.

[PyR0NiAk]

500whp is a GT35R goal, and you're sacrificing spool time... The only way I could imagine a GT35R turbo being a good turbo on an SR is going with solid lifters so you can rev the hell out of it.

[playero_loko]

I just want to hit 500whp...

not sure you'd be able to even 400 on pump gas with a .63 AR! Notice that in Full-race.com they havethe 3076R (asumming is the .82 AR) with 33+ psi on race gas (e-85) and got 573 whp... you also have to think about what dyno it was done with??? what were the actual mods on the car! not so sure you can run 30+ psi with pump gas...

if 500 whp is the goal, then .82AR is a MUST!!!

[idahotuner]

ou should be bale to do 450 on pump gas witha .63 i made 400 on pump with the gt2871. so 20 pounds on pump gas shouldnt be a issue wit hthe .63

[maverick06xx]

ou should be bale to do 450 on pump gas witha .63 i made 400 on pump with the gt2871. so 20 pounds on pump gas shouldnt be a issue wit hthe .63

Alright lets just say i do hit 450whp with this setup will it be a great midrange to 7500rpms car? thats all i would like as well, i'll be getting the spilt fire idnition system, 1 piece aluminum drive shaft to add with this setup. I could be happy if this car turns out to be a midrange to top end car with 450whp. But i'm gonna have to find a way to find a turbo that makes 500whp on pump gas and not be laggy... So you all think the .82ar is a better choice for my build and goal?

[playero_loko]

ou should be bale to do 450 on pump gas witha .63 i made 400 on pump with the gt2871. so 20 pounds on pump gas shouldnt be a issue wit hthe .63

i will go on a limb and say that this was done on a dynojet dyno, correct?

[idahotuner]

ou should be bale to do 450 on pump gas witha .63 i made 400 on pump with the gt2871. so 20 pounds on pump gas shouldnt be a issue wit hthe .63

i will go on a limb and say that this was done on a dynojet dyno, correct?

I think it was a dyna pack 1800 this is the graph

ou should be bale to do 450 on pump gas witha .63 i made 400 on pump with the gt2871. so 20 pounds on pump gas shouldnt be a issue wit hthe .63

Alright lets just say i do hit 450whp with this setup will it be a great midrange to 7500rpms car? thats all i would like as well, i'll be getting the spilt fire idnition system, 1 piece aluminum drive shaft to add with this setup. I could be happy if this car turns out to be a midrange to top end car with 450whp. But i'm gonna have to find a way to find a turbo that makes 500whp on pump gas and not be laggy... So you all think the .82ar is a better choice for my build and goal?

i would read reveiws on the spitfire ignitions because i read that stock coils are actually better. it should make power to 8000. i would like a single piece driveshaft for my car.

[HOOCH_256]

damn took me awhile to find this thread but it is exactly what i have been looking for! Im building a 240 that i just picked up and it has a freashly rebuilt SR but i want to make some bigger numbers and what not, and this is what im looking at getting into and want the advice from some pros here....


Turbo-
Garrett
57-Trim Turbo
Flow equivalent to GT3076R
P-Trim Turbine wheel
Optional 0.68, 0.81 or 0.96 exhaust housing

Cams-
256intake/264exhaust

injectors-
740cc

intake-
greddy

[idahotuner]

i would go with 264 264 cams, and did you rebuild it your self or buy it rebuilt, did you get receipts ?

[HOOCH_256]

no receipts sadly but when IntecRacing takes it apart they will be inspecting everything, thats why i decided to take it to them cause i hear they are one of the best for the SR and they have been more then helpful thus far with questions and getting back to me right away when i have a question! only thing im worried about getting is the bill lol

[idahotuner]

awe, i built mine my self and saved all the reciepts even for the balancing of the rotating mass, to show for if i ever sold the car.

[PyR0NiAk]

Ben, good work keeping up with this thread.

[idahotuner]

thanks, man. i try to stay on top of things. you should hear my latest idea though, i am hoping to put into creation this fall maybe, maybe i will make a seperate thread to discuss it.

[disenter]

Hey guys, new to this site, but came across this thread after searching for help with my cams.

Have a Redtop Sr20det, with mostly bolt ons, but I have bc 264/264 12.06mm cams, bc springs and ti retainers, with a GT2860RS (disco) 0.86 rear hanging off the side of it. Now I have all the support mods, and on the dyno it made 240rwkw, but boost is happening very late in the piece, like 5000rpm to hit 18psi on a 4th gear ramp, and after 5500rpm, its tapering back down to about 15psi...

What could be wrong? or is this what one should expect with this combination of cams and turbo?

Cheers!

[idahotuner]

the gt2860 from what i heard is kinda a mismatch turbo, or am i thinking of the gt2876.

but either way a .86 turbine housing with a t2 inlet is going to be a slower spooling turbo.
unless you have extra displacement for it.

I ran a gt2871 .86 on my car and had boost by 3300 but i also had an extra .2 liters of displacement.

also you might want to check your waste gate, did you buy the turbo new, what boost controller are you using?

[disenter]

Yeah I used to have a 2871 56t .64, but it blew and I got the disco fairly cheap second hand from a friend. Discos from what I've read should be all in by around 4200rpm in a .86. Question is whether bigger cams should make it laggier? I kinda thought since bigger cams or rather bigger lift, means more air and fuel in and more exhaust out that it should be easier to drive the turbo, but maybe it's not?
Actuator is fairly new, but just the standard item found on both discos and 2871's from Garrett.
Boost controller is a hks evc 5.

[idahotuner]

your gain maybe set low on the boost controller, and 4200 sounds about right, have you checked for boost leaks cause that could be a big reason. and actually seems like it maybe the problem.

[disenter]

Yeah ic system was pressure tested and a leak was found and fixed prior to tune, but still behaving like it's got one or something. The evc was reset up by the tuner, and I haven't seen it myself yet as its still in the shop. Was just sent the dyno sheet. Before tune it was hitting 19psi by 4600 with the cams at zero both sides, but it had a leak which it doesn't or shouldn't now, so I'm at a loss as to why after dialing cams and tuning that it's lost response

[idahotuner]

dialing in cams, why arnt they set in stock location.? you have adjustable cam gears?
what brand of cams?
did you open your throttle body when you pressure tested it to see if you have a leak around your intake manifold, or possibly and exhuast leak before the turbo.

[disenter]

hi idahotuner, the cam's were dropped into standard location, set at zero on both intake and exhaust sides originally, which I did, with some help, at home, although I didn't have a degree wheel, and just got it as close as possible by eye, and have been played with since then on the dyno to try to achieve better results, using a pair of vision adjustable gears. I think the intake cam is at about 5 deg adv and the exhaust cam is at about 8 deg ret now from what the tuner has told me. I had asked for them to be properly degree'd to ensure that they are 100% (or as close as possible to it) before attempting to tune the cams, but from what I'm told, few bother doing this anymore and just play with the gears until they find the sweet spot as it were. The instructions on the cam card fairly much tell you to just drop them in at zero, and adjust from there as necessary anyway I guess..

They are Brian Crower Step 2 264/264 12.06mm lift, with Brian Crower BC1200 springs and Titanium retainers, with some Tomei rocker arm stoppers thrown in for safety sake.

I didn't do the pressure test myself as I don't have the required tools for it myself, the workshop that's tuning it did, so I'm not sure how they went about it, but they did find a leak from the small throttle body outlet, that joins to the large intercooler pipe. The hose used is the right size for the throttle body end, but the bit that's been welded into the IC pipe for it to go to is a bit smaller, the clamp let go and so at 4.5psi, it was pretty much pissing out of there from what they told me. So they tightened the hell out of it and it was apparently holding 18psi after that, so that much at least should be ok.

Whats weird, is we overlayed a dyno sheet from before the cams were played with, and before this boost leak was apparently corrected, and the boost is dropping off at fairly much exactly the same point.... 5500rpm its tapering down from 18psi to about 15.

I had a chat with the tuner about it today and he's going to try and do some more testing to isolate the issue, but he said he's only ever had one other disco .86 sr20, as they're not such a common turbo anymore, and it did much the same with boost tapering down. But yeah, I find it hard to believe its normal... so I'm wondering if anyone else here has experience with these cams and this turbo in particular?

Cheers!
Dave.

[disenter]

I guess it probly make it a tad easier if you can see the graphs, so here's what I have.. sorry they're not the greatest quality.

Boost



AFR



overlay before and after..

[idahotuner]

dose your car sound like tractor when it is running?
here is the link i use to double check my cams have been installed correctly.
http://rs-enthalpy.com/info.html sounds like you have the same exact cams that i have.
how long have you owned them ,did you get them new?

like i said i would double check a boost leak, and pressure test it all the way up to like 30 psi. i do it by havign a cone like peice of tubing with a bicycle stem, that i hook an air chuck up to and use a air compressor to just force the air in through the turbo intlet, with the motor off. any leak at that 30psi will sound like a high pitched whistle.

try doing a base psi run with the boost controller disconnected and see how the power curve is with out being munipulated by the boost controller. this these two thing eliminate 2 factors at least. and we can see if its cams or possibly actuator.

[idahotuner]

always remember its about eliminating down to the basics

[disenter]

yeah i've had the cams since new, bought and installed them a year and a half ago odd now, actually i think it may even be about 2 years or so when i think about it.. bit of a long story, but basically, the information i had about them at the time, said that they needed roughly anywhere between 11 and 17deg adv on intake to work properly... so for a base setting and initial very rough, off boost road tune we ran them at 12 deg adv intake... enough to get it to a tuner to do the rest on the dyno.. but literally the day i had it booked into the tuner, i found some more information about them, saying that this was only true of revision 1 of these cams, and revision 2 did not need this.. just set at zero, and adjust from there as necessary while tuning... this is for redtop, non vct's of course, and as it turns out mine are revision 2. So, i told the tuner this, and told him that they would need to adjust them / degree them properly, and that i didn't care if it cost more, but it needs to be done right... but of course, this tuner didn't do that and just tuned the ecu as is...

This only produced 215kw at the wheels, with a 2871 56t .64ex behind it, and naturally was getting rather high knock readings under load and higher rpm's. I was pretty pissed off to say the least, as it cost me 600 dollars for the tune, and the tuner basically blamed the engine, said the bottom end was stuffed and was gonna fall apart if he pushed it more... but admitted he hadn't touched the cams.

So, I took it home, hitting 86 odd knock readings on my powerfc, ripped the rocker cover off, and wound the intake cam back to zero. It felt better immediately, didn't knock past 17, all the way to 7500rpm... I drove it like this, on this s*** tune for about a year and a half or something (an this is the lower reading you see on the overlayed graph above to, although it is with the same disco 86, because the 2871 blew, it is that same tune, just with the intake cam wound back to zero - yes, i've had my share of problems! lol), because i didn't really have the money to see about getting it done properly, and its been pretty difficult finding anyone who wants to even touch BC cams here in Australia, as far as degreeing them and tuning them properly. Now I have a workshop that's had a go at it, but the results are not exactly stellar... and whilst i don't expect miracles, i think 5000rpm for 18psi is a bit late in the piece for a disco 86 with BC step 2's.

The tuner has agreed to go back and do some more boost leak tests and see if he can find anything, but he didn't sound to confident about that... What I don't understand is why you would even bother trying to tune an engine that very obviously had these kind of boost issues... is it not logical to try to eliminate those issues prior to tuning??? I mean the first ramp on the dyno should have been enough to say hellooo theres a problem and we need to isolate it before moving on... or is that just me???

[idahotuner]

put both the cams to stoc positions, tuning cams can be finicky and its usually is only
a couple of degrees that people do it to eliminate overlap.

as for the cams they ran a bad batch that needed adjustible cam gears about 5 years ago, but i got mine 4 years ago and set them at exactly stock positions, using that link i gave you, and the engine purred like a kitten.

when i first installed the mine used the dimples on the cam gear instead of the dowels, and it ran likea tractor, you can see some videos on you tube if you search idahotuner first start up. then i realized my problem after chasing things all over, pulled the cames back out and clock them so they layed both front lobes facing out. stock postions or basicaly dead zero. and cranked the engine and it took off, smooth and nice.

people dont like brian crower cams and i dont understand why. they area good cam for the money. i did break one but it was my own fault when i was tightening the cam gear down on one, i sheared the lip off the end of the cam.

also if you drove around on a bad tune that had some nock, i would do a leak down test because it could be the actual engine is not holding boost, that happend on my last engine, and it got to the point where it wouldnt even hold 10 psi, but when it lost boost you could hear it like a BOV as boost shot past the piston rings

[disenter]

got to take it for a test spin today... it drives fine, but yeah is pretty laggy. The tuner had not put ANY gain/offset into the EVC at all. He just set it up 'by the book', which yes gets it to reach the target boost level, but very late in the piece in my experience with the evc .. so I put it up to 120% and it definitely came on a bit harder or earlier, but did also spike 1psi over the target of 18psi... that doesn't worry me, the tunes reasonably rich at 11.5AFR peak, so 1psi wont hurt it... but i think its still dropping boost after 5500rpm too... I've asked the tuner to try bypassing the evc entirely and just using a bleed valve to see if that is the issue, and also to drop the exhaust off it from the front pipe back, and give it a ramp and see if it makes a change... im thinking the cat may be a bit stuffed, making it not free flowing enough... hopefully i'll hear back from him monday and find out if there is any change doing that... if not, then i dunno wtf is going on. drives fine, has stuff all knock at all (saw a max of 20 on my pfc bouncing it off the limiter) just doesn't want to boost properly!! really starting to piss me off, and my tuner is getting the s*** with me asking him to try and find the problem and fix it! :\

i'll let you know when its figured out i guess!