M30 N/A Build, stock rod strength

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LKTe30
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Tue Sep 26, 2006 4:01 pm

I am building a N/A m30 to put in my e30 and have a question about the strength of the stock m30 rods.

First here is the jist of what is going to be done to the engine:
custom 10.5:1 pistons
.5 overbore, hone, resurface
head port/polish, resurface
3 angle valve job
probably a 284 cam
dual valve springs
balance/blueprint

Basically the question is will the stock rods be ok for this set up. I don't plan on having the engine rev much higher then 6500 rpm but this will be put into a road racing/drift car so it will experience the higher revs.

Custom rods are expensive and I have gotten a good deal on all the other work to fit it in my budget. I would like to use the stock rods from the donor engine, I have cleaned them and they look to be in great condition.

But can these rods handle this setup? Any advice is appreciated.
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Gunni
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Tue Sep 26, 2006 4:03 pm

yes, unless you plan serious rpmԚ´s,
what rpm limit are you going for here?
With great challenges comes great engineering.

Gunni
@ 2012 VEMS group buy !!
LKTe30
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Tue Sep 26, 2006 4:05 pm

rpm limit will probably be around 6500 maybe 6800 but no higher than 7000

On that note what rpm limit do you guys think I should use with this engine?
Andy335Touring
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Tue Sep 26, 2006 8:06 pm

If you can find them for a sensible price look at getting S38b35/6 rods, thats what Alpina used in the B10 N/A motor to handle the higher revs.

They are a bit longer but as your using custom pistons you can get them made to suit this.
LKTe30
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Location: Richmond, Va

Tue Sep 26, 2006 9:21 pm

thanks for the info, only problem is the pistons have already been ordered and are being made to be used with the stock rod length, guess maybe I should have asked this question earlier but I figured the stock rods would be strong enough. How much longer are the S38b35/6 rods?
Andy335Touring
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Tue Sep 26, 2006 9:26 pm

I don't know for definate but 3mm was mentioned to me a while ago ?
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