Need opinions on bottom end build

[NateS]

Extreme Motorsports is building a bottom end for me because a rod started knocking. I talked to the owner and got his opinion. He is highly suggesting to keep my 7 bolt and have them bore it out and stroke it. He says that I should not have to worry about crankwalk at all. He has built several 7 bolts and the only ones that have walked are the ones that the owners didn't follow his advice. He says that if you match up the clutch and hydrolics and what not there is no problem. He said most people throw in rediculously heavy clutches and it ends up causing crankwalk. He has built several 7 bolt bottom ends that have been swapped into a few different cars over a couple years and still running strong.

I asked him about the stroker crank and he says that it doesn't really matter. He hasn't heard of swapping a stroker crank will decrease the chance of CW. He is confidant enough that it won't get CW as long as I do the clutch and what not the way he suggests.

I feel like I can trust this guy seeing how he obviously knows what he is doing. Another part of me still wants to just put in a 6 bolt and not have CW looming over my head. Suggestions?

[Black99GST]

i'm very interested in the whole "clutch set up his way" i guess if it works go with the 7-bolt, and share the knowledge with me i personaly would go with the 7-bolt set up for finance reasons, and because swaping to a 6-bolt requires A LOT more work. if he says he can avoid C/W (which is over-rated anyway) just get it in writing and do EXACTLY as he states (in Writing) and then your ass is covered... not to mention, 6-bolts are older motors, and have been through alot, unless everything is re-built, and all jazzed up (even more $$$) you dont know exactly the kind of abuse the motor has seen. 7-bolt FTW IMO opcorn:

[defiancy]

Since you are building a stroker motor, you shouldn't have to worry about CW since you are putting a 2.4 crank in there.

As far as the "his way" for the clutch thing, I think he may be referring to the fact that people often put large clutches on their cars and it causes more wear and tear faster on their motor, thus causing CW to occur quicker.

But again with a stroker motor you shouldn't have to worry about that.

Taken from Vfaq 1000 questions:

A 'walking' crankshaft is a crankshaft that moves too much inside the engine. This is also known as excessive thrust bearing play. The movement is usually due to the crankshaft not fitting inside its bearings correctly. While not bad for the crankshaft, the movement can place excessive or uneven loads on the bearings, causing premature failures.

With a 2.4 crank your crank this seemingly does not apply, especially since you will be replacing not only the crank but hte bearings aswell.

[gthompson97]

From what I understand after about 5 years and reading hundreds of "theories" about crankwalk is that the 2g 7-bolt cranks were machined "out-of-spec" and cause what defiancy said, premature bearing faiulre, therefore leading to a walking crankshaft and a motor that is no longer useful.

[Thor06]

I say why fuck around, drop in a 6 bolt. I'm not much on strokers, I would rather have a 2.0 that can rev out to 9 or 9.5 than a 2.3 that shouldnt go past 8. 6 bolt swaps can get spendy though, especially with someone else doing the work. What are your plans for the car? If you are just planning on running a 16g or something, best bet would be to just rebuild the 7 bolt and drop in a 2100 or something. If you're looking for 350-450ish I would say do a 2.0 6 bolt. I wouldnt go with a stroker until I was looking to run something bigger than a GT35R, even the 35R on a 2.0 wasnt bad at all.

[gthompson97]

GT35R FTMFW!!!! Too bad you won't know what that power feels like Dustin.

[Thor06]

Wanna bet bish?

Ha ha, lets see... quick summary of the night. Went to drink and hang out with the local DSMers and I ran out at like 12. At 2:30 people started leaving and the guy I was going to get a ride with was too drunk to drive. So that leaves me . It was a red 97-99 GSX with link (hooked up to an indash 7" monitor BTW) and all the goodies to support the 35R hanging off the exhaust side. So there we were cruising on the highway back to school and hes like why are you driving like a pussy? So I put it down, 100-120 and weaving in and out of traffic FTMFW . Shit was awesome. Oh, and 25 psi on that turbo sounds wicked as hell when you are running through the gears.

[gthompson97]

Originally Posted by Thor06

Wanna bet bish?

Ha ha, lets see... quick summary of the night. Went to drink and hang out with the local DSMers and I ran out at like 12. At 2:30 people started leaving and the guy I was going to get a ride with was too drunk to drive. So that leaves me . It was a red 97-99 GSX with link (hooked up to an indash 7" monitor BTW) and all the goodies to support the 35R hanging off the exhaust side. So there we were cruising on the highway back to school and hes like why are you driving like a pussy? So I put it down, 100-120 and weaving in and out of traffic FTMFW . Shit was awesome. Oh, and 25 psi on that turbo sounds wicked as hell when you are running through the gears.

Yeah yeah yeah, that's an old story.

What I meant was, you won't be able to feel it whenevvvvvvvvvvver you want....unless you got some big plans for that slow white mobile. opcorn:

Originally Posted by Thor06

(hooked up to an indash 7" monitor BTW

7" touchscreen Farenheit by any chance? Those screens FTW, the Z and Talon will both be getting one.

[Thor06]

Wait, what kinda Z did you get? Fuckin rich ass sugar beet farmers .

Yeah, the Cavalier is getting built as we speak, when I get home I will jimmy rig DSMlink to it and hang a 35r off it. No Garrett, Slow White is called Slow White for a reason... because its slow. Ha ha, did you know that you are doing extremely well to squeeze more than 250 hp out of it? I wont get a fast car until I get an M3 when I graduate college and the Cavalier dies so literally like 2012 or so. In between them I might get a rocket which would mess up or atleast stay with a 35r car if I could figure out how to drive.

Sorry for the OT everyone, original poster what are your goals and funds situation like?

[gthompson97]

That is for me to know and you to find out at a later time. And yes, sorry for the hijack......back to the original post!

[NOFX0617]

I would say just go with the 6 bolt man...if you are going to be putting that much money and work into it you may as well do it so your not worrying about it...so far I have to say that the swap is really not that hard....

[NateS]

Well I think I'm sticking with a 7 bolt, boring it out, and stroking it. My final goal for the car is in the 550-600hp at the crank. After everything is broken in and what not I'm planning on getting the car tuned for the maximum output of the 50 trim on it now. Should be a fun weekend car