ethan169

iTrader: (3)

I hate to make a whole thread for this but I couldn't really find an existing thread to post in that wasn't completely dead.

Ill try to make this straight to the point

03 VIII with stock turbo
S2 w/beehive springs
TBE w/HFC
ETS LICP
ARP Head studs
Perrin Inline MBC set at 25psi
MAF adapted with K&N filter (stock tube)
IX DV

I think that essentially it

For ECU stuff I do have the JDM Map sensor and an LC1 for boost and AFR (wow thats a lot of abbreviations lol)

So I run 93 pump gas I try to stick to names like Shell and Mobil but I dont always have that available.

Why questions is 25 pounds on the stock VIII turbo too much? The car seems to run fine and I assume when this cold weather goes away i might even come down to 24psi with out touching the mbc.

The car dynoed on Ivey's dyno with the previous tune from Mellon wich when he tuned the car did not have the cams in it! I just wanted a dyno tune to dial in the cams etc. and get some numbers...

-so baseline pull was 303.44whp and 313.05tq

-After the retune 317.63whp and 315.78tq

I think one of the pulls that he did that is not shown on this graph he got 321whp and 318tq but maybe it was knocking and he pulled some timing added some fuel?

He said that the gas that I had in there may have been "bad" because it was inconsistent with some low count knock. There was heavy traffic that day and I was driving down the lynden NJ from VT took a little over 4 hours with traffic. So I stopped at the first gas station one i finally got over the George Washington Bridge and filled up because i had no other place to go.

Ive posted the graph below.. unfortunately the network scanner I have here at work does not scan in color which is SUPER lame. But ill work on a color version and try to post that.

Mellon Racing

iTrader: (38)

that does seem odd...

so a baseline pull was done with the old Mellon Tune that was completed a long time ago before you had cams did 303.44whp and 313.05tq

then the Ivey retune (with S2 cams) was 317.63whp and 315.78tq

That car should be in the 350+area, was a boost leak test done with an air compressor?

25psi is not pushing it too hard.

ethan169

iTrader: (3)

I was not able to do a boost leak test before I went to NJ for the tune but I have done leak test periodically because of my constant paranoia that I have a boost leak. Chris I don't know if you remember the trouble we had finding the boost leaks in my car that basically ended up being TB shaft seal and a few other minor spots.

These previous tests are basically useless now though because this was all before the cam install was done. I had the head off as well to do a head gasket because we didnt realize there was a shrater valve in the compression tester so there was no pressure in the cylinder and CLINK went the first valve when doing the springs on the car.

So basically I need to check for leaks which I will this weekend when I return home for the holidays.

But I was expecting a little more gain from the retune with the cams. I mean just the cams alone untuned the car already felt WAY different and pulled hard down in the midrange anyway. I didn't want to push it without a solid tune.

Sean said the numbers were right on par for an VIII with cams like these, and my biggest restriction was my HFC. Said i would get a lot of gain from a test pipe and a UICP? I thought ive always read that the UICP wasn't really that big of a restriction. Of course i don't believe everything I hear.

Mellon Racing

iTrader: (38)

if you find and fix some leaks I would keep an eye on the knock and AFR as it may change now that air is going into the engine instead of around it.

you could also do a compression test to make sure the engine is healthy. If you have a cylinder that's very low, try adding a teaspoon of oil in the cylinder and test that one again. If the pressure jumps up to where it should be then you know the rings are worn pretty badly.

double check the timing as well, belt can jump teeth and throw everything out of whack and kill power or worse wreck the valves.

I agree, the HFC is choking it some, some are better than others but none are better than a test pipe

I don't think the UICP is going to make THAT much difference either, but I haven't done any back to back testing to verify this.

you're still rocking the stock FMIC right? regardless, I'm not certain you'll see huge gains going to a race fmic in this super cold weather.

cij911

iTrader: (14)

Although it does not sound like you gained much from the new cams and tune (based upon the the peak numbers), what does the power curve look like ? Did you gain a lot in the mid range ?
Something does not sound correct - 8's are supposed to really benefit from cams as the stock profiles are very mild.

ethan169

iTrader: (3)

Thanks Chris - So Ill do a boost leak test and fix anything that I find. Then run some logs etc. As far as the Cam timing Im assuming that the only way to check it is to take the timing covers off again which would require taking a few other things like serpentine belt side motor mount etc to see right?

I had a friend do the Install with me and hes pretty known in my area for working on Evo's etc. Been messing around with them since he got his back in 03 and doing installs for basically everyone that I know in my area anyway.

Either way we check the timing for a good solid 40 min i wanna say... cranking it over by hand to make sure the notches all line up when they are supposed to. I mean ive been running the car for almost 1k miles now which was mostly highway from driving down to NJ from VT and back and I haven't had any issues. So I doubt there is any timing issues or worse valve damage. Im sure i would have noticed something.

As far as compression testing I will give it a try when i can get my hands on a tester. But when we had the head off everything looked extremely tight and clean. Especially for 60k on the clock. Of course we couldn't really check the rings etc but all valve seats and seal etc were in great shape and the turbo had absolutely no shaft play, axial or radial.

To give you an idea of how my car is condition wise im still on the stock clutch and no slipping even after 18 or so pulls on iveys dyno and a handful at swift in addition to my daily commute to work which includes many 3-5 pulls Of course i dont expect it to last much longer. But I also expected it to be done at 15k lol...


-Ethan

ethan169

iTrader: (3)

I have attached a shot of the dyno graph that includes a base pull and the final pulls. Although its in black and white they are all pretty close as you can tell.

I didnt seem to gain much in the midrange either. From what it feels like to me is that the car pulls almost like it did before the tune (to be clear this means with the s2's installed but a previous tune that was done before cams were installed) Only difference in feel is that it seems to be a bit smoother in power delivery, especially down low like while milking through the gears during normal driving. Not so much lag then boost constantly down low, just smoother. Sorry if that doesnt really make sense.

And yes i was under the impression that the cams are supposed to help the VIII's quite a bit too. Which they certainly did, I don't need a dyno to tell me that I can feel it for sure. But the tune itself didn't really give me any gain. I mean were talking 5hp or tq.

I was always told the tune was the best bang for the buck. I just spent quite a bit on 5hp/tq lol

I dont really want to get hung up on the numbers but I do feel like something is up here. I just want to car to perform like it should with the mods I just put in. I wanted to bring the car to another level that could keep me satisfied for another year or so.

Chris- I am still on the stock FMIC. sorry forgot to add that in the last post.

-Ethan

cij911

iTrader: (14)

I am sorry, but I may be misreading your statement... Did the 'baseline' dyno numbers have a Mellon tune for 25psi and the new S2s installed and then the final numbers just tweaked the tune for the S2s ? If so, then I understand your results....

Mellon Racing

iTrader: (38)

I tuned the car before it had cams a long time ago, Ethan installed the s2's and did a baseline dyno pull with my old tune still on it. Then he had Ivey tune it for the s2's. I haven't tuned it for the s2's, but I'm very loyal to my customers and would like to help him figure out what's going on because I really think the car is capable of more. My guess is that there's either a mechanical or octane issue, I think Ivey did the best he could with what he was given to work with.

ethan169

iTrader: (3)

This is correct. Mellon's tune was at 23psi. The base line pull was with literally no changes to anything involving the ECU or MBC.

-Ethan

sk8terdude929

iTrader: (2)

You shouldn’t have a problem with that boost, I know I run 27psi on a FP green as I did with my stock VIII turbo on 93 without any knock. As for the HP I don’t know, it seems like a lot of the people with S2's are at least around 350ish like Mellon stated but I’ve heard Ivey is a great tuner so I wouldn’t be worried. If it was bad gas though, why not try to drain it and get some fresh gas and run it on the dyno again to see if it is consistent

cij911

iTrader: (14)

To OP - Well its hard to say since the baseline already had a solid tune and the s2 cams. Had you done a true baseline with the stock cams, then you'd be able to see the real gains...

ethan169

iTrader: (3)

Update on this situation...

I did a boost leak test and did find a decent leak. Fixed it car seems to hold pressure properly now. I took a few logs and noticed that Im getting quite a bit of knock on WOT pulls and some random knock at very low load and rpm and no boost. I am being told its possible that I may have a loose knock sensor or even a faulty one. Im not 100% on where the knock sensor is but Im assuming its on the back lower section of the block itself? I don't remember removing the sensor of the plug from it. But Ill have to check when I can get a chance.

I have attached some logs. One of them has a 3rd gear pull in it. They both show knock in random spots 1-3 counts with very low TPS and no boost. The ECU is pulling a lot of timing during the pull. It gets down to 3 deg timing etc.

Take a look if you can get a chance and tell me what you guys think. Is it a knock sensor or maybe my exhaust rattling? I certainly don't hear it rattling and Last time I looked at it it wasn't making contact to any part of the Tcase. Its the Buschur TBE with HFC if that matters.

Thanks guys

-Ethan

ethan169

iTrader: (3)

bump for anyones input on my random knock???

Mellon Racing

iTrader: (38)

it's most likely real, doesn't look random to me.