blau928

Hi Tuomo, thanks for the clarification.. I did not know Dema and Jim are collaborating.. Great stuff then..

Hi Greg,

The graziano box is also expensive, so is the ZF unless I find a smashed 599, and even then, it will no doubt cost an arm and a leg.. So, maybe I am stuck with the auto until I find out from Weismann what they want for theirs.. And it may also cost a bunch... Like I said, I have not heard from them as of today.

As far as crank cost and materials, I think Chambon was on the upper end of your scale. Moldex mentioned 4340, and I am fine with that as long as it is a billet piece.

The oldone site is very informative, and has a lot of information. The S2000 heads in wild form are 400 Int/320 Exh, look there..

With regard to my redline, I don't disagree with you, as piston speeds get high, and I am designing the thing as a street motor, so it's not neccessary to go to 8K all day long. However, I would like to be able to in a pinch and not worry that the motor will disintegrate.

I do have a preference for Carrillo, Arrow, Lentz etc., depends what I find when I am ready to buy. I don't want custom pieces, so I may get lucky with some team having a matched set they want to get rid of.

If you go dry sump, then the counterweight issue will be negligible, as the crank is spinning in a vaccum as you noted. I am looking at this, and evaluating... On a street car, no space for a tank for the DS.. I may run a vaccum pump instead, and hook it to the oil filler, pre vac pump, pump, then to a scrubber, and then to a separator with a drain to the sump area to have the same effect.

All cranks will break from detonation, regardless of what they are made of.. I am sure of it.. I don't plan excessive forces, and Moldex has made good stuff that has worked well in past, and I think it will be fine for me. I also want billet 4340, not a twist 4340... The secrecy you noted is with a lot of parts makers.. I think the strength comes with the forging, the resiliency of the material, and the finishing of the piece. Balancing is also key..! Polishing does a lot, and the crank must be able to bend, have low harmonic distortion etc. That's why I will have the crank cut last. The trick I found is to balance the entire rotating assembley to a small a tolerance as possible. So, I need piston weight, pin weight, ring weight, spirolock weight, rod weight, and bearing weight, and then tell them what kind of oil I will use. They will then take the individual bobweight of each journal, and then cut the crank accordingly. Pistons, rods, pins, rings, bearings are all numbered by cylinder, and stay there when assembled...

Anyway, great to hear from you as always, look forward to updates on your build, and comments on the science etc..

Also take a look at the civic build in the archives on Larry's site.. A little 2.0L pushing more than 190Lb/Ft and 300HP and Normally Aspirated. More importantly, I was impressed in the rate of change in torque over the powerband, the Lambda, and the VE.... If interpolated to a 7.0Liter, the results are pretty interesting..

I like that NASCAR stopped using the 2.0 journal stuff, so the really good parts will be cheaper, and like I mentioned, some team or some shop somewhere probably has a box of perfectly new rods waiting for me to send a check...

As far as the economy in detroit, it's everywhere, and some prices are falling, and others are through the roof..! Anyway, story for another time...

Cheers,

docmirror

BTW, the S3 cam mod is avail from a company on the left coast for a lot less money.

svp928

Richard, there have been some threads here describing the Chevy rods not ending up centered in the piston due to the difference in bore spacing and cylinder offset betw chev and 928- you might look up those threads for more info....

Steve

Jim Morton

Doc:

Good info. Please let us know the name of the "left coast" source.

If the S3 mod work can be done cheaper, I'll send all/any work there !

Please know that for what I have charged, the job is a money loser and simply done as an assist... so a cheaper source is no loss to me

ptuomov

docmirror, Jim Morton --

I doubt anyone will do the S3 to fit S4 mod cheaper than Jim. Jim charged me $400 for cleaning, inspection of the lobes, driver's side thrust mod, notching for shortening, etc.

If the alternative provider is cheaper it almost doesn't matter how much it costs because at this price range I am going to compare the quality of the mod and decide based on that.

For the record, since there has been a lot of guessing on various forums, here are the prices that I paid to Jim Morton for the modified cams. I had two sets modified, the first just with S3->S4 mod while retaining the stock S3 profiles and the second both modified S3->S4 and then reground to Elgin's 65-6 profiles.

The second set, Elgin 65-6 regrinds based on S3 cores:
- S3 cores in good condition from Oklahoma Foreign Motors, $350
- Clean and prep camshafts for work, $60 (this I could have done myself)
- Drivers side thrust mod, $300
- Regrind all four cams by Elgin Cams, $800
- Shorten cams, or notch for future shortening, $120
- Gas nitride heat treatment, $200
- Final straighten / Parkerize / QA, $100

Total per set, $1580 + $350 for cores.

The prices assume that there are four or more cam sets going in at batch, so delivery time depends on how many people are ordering at the time.

Why accumulate all these cams? I am planning to pay for a couple of days of dyno time to test cam alternatives with the Kuhn twin turbo system. If that plan materializes, I'll report the results.

Best, Tuomo

docmirror

Doubt away, it's a semi-free country.

ptuomov

That it is! ;-) I could go on a political rant here, but this would lead the computer that logs my web activity to NSA flag me and I would be classified an enemy combatant for denying honest services and giving material support... ...so I don't do that.

Out of curiosity, who makes the S3 -> S4 mod cheaper than that, and more importantly, what method are they using? Also, do you know of a company that would do custom crank drilling well for a reasonable price?

docmirror

So, let me get this right. first you doubt that I can get it done. Then you implicitly impugn the quality of work that you've never seen, then you want me to give you the name and address of the vendor, and prolly his price too?

Do I have that right?

Jadz928

Since this is already a divergent thread, I think I may ask away.... and since there is some cam talk.

Does anyone have any experience using GT intake cams with some other exhaust cam config?

blau928

Hi Steve,

I have heard about this, and have been asking about rod thickness on the big end, and also about the stock rod widths etc to try and figure this out.. So far, I'm not getting any inormation from anyone who had the specs handy. I remember back in the day, Marc T said no problems using the chevy rods, but Greg b told me that there were issues, so I wanted to double check..

I'll do a search for rods and see what I find here..

You still in my area..? Have you gone to the CV concours lately..? I have not done anything with the PCA club in ages... I think I saw you driving on Hwy 68 during historics, another time on CV road.. (I was in the Range Rover, and we were both going quickly, so I didn't wave..)

Thanks..

ptuomov

No, you have that completely wrong.

What you wrote above reads to me as you being pissed off at me. I am going to assume that I somehow wrote something that could be interpreted in a way that is insulting. Apologies, this was not the intent.

I doubted that someone could do the S3->S4 mod for less than $400. The reason for me doubting this is that at least the way that Jim does it requires a number of steps and I think it's hard to make a profit selling that for less than $400.

I also didn't see the price posted here anywhere, so I didn't know if you meant it can be done for less than $400. I just intended to say: "Really, can you get this done for less than $400?" That's all.

I also said that if it costs $400 or less, I personally would then choose based on quality and not price. The reason for this is that the work of changing the cams, the new lifters, etc. is going to be pretty expensive, which means that the thrust mod itself is relatively small part of the total package price. It's more important for the cams not to fail. I understand that not everyone has the same approach as I do, and many people can source the rest of the project cheaper (already has S3 cams, no outside labor, using polished used instead of new lifters).

I didn't imply anything about the relative quality of Jim's work or the unnamed vendors work. In fact, I was interested whether your vendor has a solution that is better than Jim's. I didn't rule that possibility out in any way. Simply wanted to know if they had a superior solution (mainly more reliable, if it's cheaper it's probably simpler which means it's possibly also more reliable). Or perhaps you think that both solutions are so reliable that there is no relevant difference.

At this point I don't need more S3->S4 cams, but I am sure others do. So posting the vendors name, address, and price here was just me being curious. It is something that might be useful to others. But to be honest, I wasn't being altruistic, just nosy.

I do need some other things done, so I was wondering if you know of a shop that could do crank drillings well and economically.

For clarity, I don't have any business interest in any 928 related project anywhere. In fact, I have decided that if I ever have to sell something that I don't need I will sell it at or under cost. So I don't have any commercial interest in any of this debate.

Hope this clarifies.

cold_beer839

Tuomo,

Are the Elgin 65-6 regrinds more aggressive than the S3 cam profiles?

ptuomov

Yes, they are. Jim can describe them better, but my best guess is this. Before I get crucified please note I said guess!

Set 2
Intake Stock S3
Exhaust Stock S3
LSA 114.0
Intake LCA 120.5
Intake advertised duration ?
Intake duration @ 1mm 219
Intake duration @ 0.05" 214
Intake lift mm 10.0
Exhaust LCA 107.5
Exhaust advertised duration 236
Exhaust duration @ 1mm 205
Exhaust duration @ 0.05" 200
Exhaust lift mm 9.0

Set 4
Intake Elgin/Morton 65-6 on S3
Exhaust Elgin/Morton 65-6 on S3
LSA 114.0
Intake LCA 120.5
Intake advertised duration 260
Intake duration @ 1mm 222
Intake duration @ 0.05" 217
Intake lift mm 10.4
Exhaust LCA 107.5
Exhaust advertised duration 246
Exhaust duration @ 1mm 213
Exhaust duration @ 0.05" 208
Exhaust lift mm 9.4

I have the exact camdoctor file for stock S3 profiles, but I didn't use those files for this info. I just guessed, based on the EAP output (that used the camdoctor files) and manual. The Elgin 65-6 profiles are based on the cam card and augmented by my guesses. Jim should (and undoubtedly will) correct me if these guesses are too far off.

svp928

Richard, yes I am still here...I hadn't seen you around town or here on the forum, so I thought maybe you moved away..good see you back!

I would ask Greg B specifically- I can't remember the thread, but I believe Greg or Vilhuer may have talked about rod spacing..

Rob Edwards

RE: Rod spacing discussion, perhaps here, page 4?

https://rennlist.com/forums/928-foru...er-tech-4.html