I started assembling my motor last night and everything was going relatively smoothly. Crank endplay measured .004-.005, so I was happy about that. I am using (or was planning on) a relatively stock rebuild with new seals, rings, bearings, etc. I just want a solid motor for bolt-ons. Anyways, we go ahead and align the rings and put the first piston in. I then started searching the internet for the torque specs on the stock rod bolts (7 bolt) and found 18 ft/lbs with a 90* turn after. And then I found out that they are not reusable. At this point I was pretty upset being that we were all ready to have the short block done. I was thinking of alternative rods today, instead of just replacing the rod bolts on those scronny 2g rods. I know they can machine 1g rods to fit, and even evo rods to fit the stock 2g crank and bore. I figure instead of wasting 60 or so bucks on new bolts why not just fork out a couple of hundred and get those weak stock 2g rods out of the equation. Because those will be the only thing holding me back after so much hp.
So my questions are-
What do you guys suggest given the situation?
What needs to be done for the evo rods to be fitted to the 2g pistons?
What needs to be done for the 1g rods to be fitted to the 2g pistons?
Are there any other cheap alternatives that will work with the stock bore and crank?
Thanks a lot guys! Any replies are welcome!
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Caleb
Yes I'm the 14th owner
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You could get a hole set of evo pistons and rods and put them in! The only thing that needs done is, the little valve grooves on top of the pistons need cut a little, on the exhaust side of the pistons.. So now the exhaust side of the evo piston will be on our intake side of the motor.. Or you could find out if you could just spin the piston's on the rods!
Hope you understand what im trying to say here!!!!
You could get a hole set of evo pistons and rods and put them in! The only thing that needs done is, the little valve grooves on top of the pistons need cut a little, on the exhaust side of the pistons.. So now the exhaust side of the evo piston will be on our intake side of the motor.. Or you could find out if you could just spin the piston's on the rods!
Hope you understand what im trying to say here!!!!
I'm not trying to get the pistons too... that will end up costing more than I want to spend. I'm just looking for rod alternatives.
Can the evo rods be machined to fit the 2g pistons?
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Caleb
Yes I'm the 14th owner
But doesn't putting the evo pistons in backwards as needs to be with our motors esentially turn the wrist pin offset to the opposite side? The wrist pin offset is very important to the durability of the rod because it has to do with the angle of the rod where peak cylinder pressure is applied.
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Matt
dd '90 GST, Holset H1C
But doesn't putting the evo pistons in backwards as needs to be with our motors esentially turn the wrist pin offset to the opposite side? The wrist pin offset is very important to the durability of the rod because it has to do with the angle of the rod where peak cylinder pressure is applied.
Yeah, thats why you cut the valve grooves on the top of the pistons.. The peak cylinder pressure will be at the same point on our motor.. As long as the little dot on top of the piston is pointed to the timing side of the motor, the piston and rods will be spinning the same in our motor, as they would be in the evo motor...
The thing is that the dsm head doesn't even use the valve "grooves" that the evo piston has cut into them.. If you look at stock 2g pistons and evo pistons the valve clearance grooves are further out on the evo.. I have seen a block with evo pistons skip time and smack the valves and the gashes in the evo piston aren't even close to the grooves..
You mainly are after making sure that the offset is correct.. That is a big deal like Dsm-onster said.. It takes alot of stress off the rods and i would imagine the stress would be very bad if they were installed wrong..
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-=John Whalen=-
WH1C w/ .55ar BEP
Yeah, thats why you cut the valve grooves on the top of the pistons.. The peak cylinder pressure will be at the same point on our motor.. As long as the little dot on top of the piston is pointed to the timing side of the motor, the piston and rods will be spinning the same in our motor, as they would be in the evo motor...
Didn't understand why you said that until now . If the offset is the same then this is a great budget option. The rods and pistons are forged. . .Though weaker than typical aftermarket forged internals. Teh forging makes the pistons stronger than all stock dsm pistons. and perhaps the forged rods just might be about as strong as the much bigger 600whp 6bolt rods. No machine work required except cutting the reliefs. . . I've gone through pistons several times with the 6bolt rods hanging on just fine. If these rods are about as strong as 6bolt rods then you have VERY good budget durability.
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Matt
dd '90 GST, Holset H1C
There not just gonna "pop" in, your still gonna have to have a machine shop put them on, but there is no machining needed.
well yea, you know what I meant... or at least I did.
Anyways, thats awsome. Will they need to do any honing or will they work fine with new bearings? Speaking of bearings, will my acl 7 bolt 2g race bearings work with the evo rods?
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Caleb
Yes I'm the 14th owner
Yes all evo's are seven bolts thus you can use 7 bolt bearing...Sorry bout not getting back earlier to you but no machining needs done but you should take the items to a machine shop to get the pistons pressed on the rods...Put some new bearings in, and rehone if you must...Othwise slap them in there...
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Jim
99 GSX 60K Original Miles
Yes all evo's are seven bolts thus you can use 7 bolt bearing...Sorry bout not getting back earlier to you but no machining needs done but you should take the items to a machine shop to get the pistons pressed on the rods...Put some new bearings in, and rehone if you must...Othwise slap them in there...
Awsome thats great to hear... I think thats what I'll end up doing then if I can find a set of evo rods before the end of the month. Otherwise I'm just going to have to put new bolts in the old ones because I am really running out of time. Bumming rides from friends and family gets old. Where are some good places to look?
Oh yea, what evo rods are best to get? XIII, IX?
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Caleb
Yes I'm the 14th owner
Shit, sorry I didn't get back to you, but I'm not exactly sure 100% on the difference between Evo VIII and IX rods but I know for an absoulate fact that the IX's ARE forged...not 100% certain on the VIII's but I don't think that they are....
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Jim
99 GSX 60K Original Miles
Alternatives to stock 2g rods
. If the offset is the same then this is a great budget option. The rods and pistons are forged. . .Though weaker than typical aftermarket forged internals. Teh forging makes the pistons stronger than all stock dsm pistons. and perhaps the forged rods just might be about as strong as the much bigger 600whp 6bolt rods. No machine work required except cutting the reliefs. . . I've gone through pistons several times with the 6bolt rods hanging on just fine. If these rods are about as strong as 6bolt rods then you have VERY good budget durability.
