heh well plugs and leads didn't seem to do anything :/ still has the dead spot.

dizzy cap and rotor seemed to be in OK condition too, cleaned up the contacts anyway. at a bit of a loss what i can do next now...!

might be time to take it somewhere and let an expert look at it

for some reason i still suspect the knock sensor... is it possible its giving out 'knock' signals even when its out of the block? anyway i could test it? (aside from getting a new one...)

Might be just a bad grind on the cam

Im also having problems with the massive dip where the BBM switches over...
ran on 2 diff dynos with same results. Im running RPD 3 cam with extractors intake etc....

recently ive fitted a chiiptorque HP4 chip with the hop that it may sort the thing out, but have not run it on the dyno yet.

any updates on your issue yet?

Is it possible that with the new cam profile the optimum point for switching the BBM is no longer 3800rpm?

i had this problem and it has since been fixed...
what i did was...

1. there is a grub screw which controls the amount that the butterflies open/close... play witht this grub screw till you graph reads right, 1/4 of a turn at a time, its hard to feel on the road so you will need more dyno time to do it properly... the grub screw is on the swinging arm of the actuator, similar to the idle speed screw which adjusts the opening of the TB butterfly...

2. advancing the timing also helped it (i cant explain why, but it helped lean out the richness at that point)

try these 2 things and let us know how you go...
you should pick up power across the entire range, but mainly at that switchover point...

cheers

I had a look at the distributer and it seems ok, gave it a clean up anyway.

I havent advanced the timing yet, but would like to. However I am building an MS2 at the moment and I have to get an EA sold so its out of the way.

I havent really taken the car over 2.5k for a while so, not too sure how its going.

have you checked the condition on the of the coil?
Make sure it has at least a 12v power suply and make sure it is putting out a good spark.


if you can try and borrow an MSD blaster 3 or blaster SS coil and hook that up and see what happens

no updates yet... ! aside from leads/plugs not making any difference, the coil looks new, but i;ll do some testing. thanks for the info fast XR, what i think i will do is wait until i get the 3" intake i am buying in the group buy in the f/s forum, throw that on, put the vernier gear on that i have here, then try and arrange some dyno time and try and work it out ($$$ will be the problem...urgh).

I also want to make sure the chain guides are OK and not being eaten somehow, because the car has a bit of a "whine" which sounds a little like a supercharger... a couple of others with the RPD cam's have mentioned it iirc, what could be the cause? it is a little worrying.

also the car is getting much better fuel economy on std unleaded vs. premium now? wierd eh...

the thing that is annoying me is all the money on random things lol... leads, plugs, sensors, stuffing around, none of it making any difference, and im picking up a new set of rims/tyres for it on the weekend too (more$$$ dammit), and the brakes feel like they need some attention - nice and smooth when cold, but when they are hot it feels like a rotor is warped? gah stupid car. close to just putting the std cam back in lol, or find another one, maybe a s/h JMM cam

Last edited by forsaken on Sat Aug 11, 2007 6:59 pm, edited 1 time in total.

you shouldn't have to spend money to find out what the problem is,

Carry out proper checks of the entire ignition and feul systems, proper checks of the entire managment system from the ECU back to all sensors and other components. Refering back to to either a factory shop manual or a haynes or gregory's manual.


it won't be the cam profile causing it, i've used the same cam on a few cars, one ended up with chain noise but they all ran very well. even when in the car that was auto it still drop the 1/4 time by about half second, and picked a about 4MPH. Wich is not to bad considering the 3.08 diff and the stock converter holding the car back.

yeah... i mean it really has to be something to do with my car - (not the cam) but i haven't been able to find much else wrong, no error codes etc, or other symptoms which can be pinn'ed downed to certain sensors or components.

i mean, apart from the lump of midrange missing, the car drives great, smooth, idles ok, doesnt stall, rev's much nicer with the cam. I dont really notice it too much around town because it rarely gets rev'ed out in anything other than second, and you can only really feel the hole in 3rd/4th, in second it is over it too quickly. but its still s**t me and i wont be happy until i get it working properly...!!

even without dyno time, turn the butterfly screw on the bbm half a turn, and drive it, if it makes the sudden drop off even worse) turn it the other way until you can feel more of a smooth transition on the switchover of the runners... half a turn makes a big difference!

will be interesting the next time i jump on the dyno (looking at Joe from crescent motorsport.....) because fast-xr and myself adjusted the grub screw on my BBM switch over to match his exactly. he actually did the dirty work of taking the whole top half of the bbm onf and aligning it by hand.

So yeh once i jump on the dyno again we can have a look and post the results...

thanx again for that vince...

hey... had a look at it today, which way did you go from stock setting?

or, how many turns are yours from completely in or whatever

 

 

Attachments:

IMG_0168.jpg [ 20.51 KiB | Viewed 133 times ]

its 13.5mm from the end of the screw to the back of the little plate, u will need a vernier or something to get in there and measure it properly, you need to be reasonably accurate, 0.5mm matters..
let us know how it goes!

 

 

Attachments:

t_img_0168_200.jpg [ 14.84 KiB | Viewed 131 times ]

hey, just checking to which side you measured, yellow or blue line?

i adjusted it so the blue distance = 13.5mm ( was probably about 3-4 turns for mine :O), ie length including the thickness of the mount plate. will see how it goes when i go to the movies later

 

 

Attachments:

IMG_0168.jpg [ 26.94 KiB | Viewed 131 times ]