zeeboost Posted November 22, 2004 Share Posted November 22, 2004 First off, lemme go ahead and give you the situation. The v8 has been pulled out of my zx and is torn apart now due to excessive blowby and lack of performance -- I found some wear marks on the crank journals, a couple of cylinders that need to be honed, and a couple of rod cap bearings that are scored. In about 7 months from now, this will be my PRIMARY driver, so I can't afford to have this 355 to give me problems in the future. It's set up to make about 400 hp and 420 ft/lbs. according to Desktop Dyno, so it's obviously not stock. I'm wondering if I should replace the bottom end with an Eagle bottom end so I won't have to worry about any trouble from it in the future, or if the stock internals will work. I've heard that stock rods are supposed to be good for 350 hp or something like that, and I'm not sure about the crankshaft. I did try searching for this information, but found little help. My dilemma: I have 3 weeks to put the v8 backtogether and drop it in my car. I need somebody to please advise me on if I should upgrade the bottom end to Eagle (this will include their forged pistons and rods, along with their cast iron crank), or if what I have should have a lot of life left, or if maybe I should just get the Eagle rods b/c my crank will still be good, etc. If money wasn't a factor then I wouldn't be posting this, but I still have a few years of college left, so I can't really go balls out on an engine setup. Plus, I'll need to make a decision very quickly b/c I have to order the parts tomorrow in order to give me adequate time to build it and drop it in. If you have any other suggestions, please let me know. 2) Can somebody identify (mostly, if you know the brand) this piston for me? I've never seen that symbol on one before, so I wasn't sure who made it. Thank you all for the help -- I've been searching hybridz for the past couple of days, but I couldn't find anything that would help me. I just found many different questions on engine builds, and that grumpyvette seems to like Eagle rods. Thanks again Quote Link to comment Share on other sites More sharing options...
Tim240z Posted November 22, 2004 Share Posted November 22, 2004 Pistons appear to SpeedPro Brand http://store.summitracing.com/partdetail.asp?part=STL%2DH535CP30&N=110&Ntk=KeywordSearch&Ntt=speed+pro+pistons Quote Link to comment Share on other sites More sharing options...
80LS1T Posted November 22, 2004 Share Posted November 22, 2004 So do you want to know if you can reuse the pistons, rods, and crank or do you want to know if you should go forged? I say if your not sprayin N20 then you should be fine with some Hypers, a slightly upgraded rod(say poweder metal rods, supposedly good to 450-500HP) and a cast crank. Now if you have scuff marks on your crank, are you sure its salvagable? Guy Quote Link to comment Share on other sites More sharing options...
zeeboost Posted November 22, 2004 Author Share Posted November 22, 2004 It looks like the marks should come out easily with an emory (sp?) cloth/pad. I know that I could reuse the rods, crank, and pistons -- the question is would it last me? Would it be something to where I'd be scared to punch on it in fear of something breaking on me? I just don't really know the limits of a basically stock crankshaft and rods, and I don't know if 400 hp would be too much for them. Thank you so far for the replies. Quote Link to comment Share on other sites More sharing options...
80LS1T Posted November 22, 2004 Share Posted November 22, 2004 Whooooowoooooooo now! A crankshaft journal is not something that you want to be touching up with emery cloth! A crankshaft journal that has scratches in it will either need to be turned down or if they are really really small scratches you might be able to just have it polished. In my opinion I would say as long as this is not a race motor the power that your putting out would be safe for the set up you have as long as your not beating on it all the time. But I would listen to some others guys who have more experice then me on this one. Guy Quote Link to comment Share on other sites More sharing options...
zeeboost Posted November 22, 2004 Author Share Posted November 22, 2004 Yeah, I wasn't sure about that one. I was just going to take the crank to the machine shop to see what he could do, but after work one of the other techs came back to my house to have a few drinks, and when he looked at the crankshaft journals he said that it shouldn't be anything, and just to lightly brush it with emery cloth or steel wool. But then again, maybe he already had a little too much to drink Thanks for the warning Quote Link to comment Share on other sites More sharing options...
zeeboost Posted November 23, 2004 Author Share Posted November 23, 2004 Any last suggestions before I call Summit? So far, the list is: 1) Eagle SIR I-beam forged steel connecting rods 2) Centerforce Dual Friction clutch assembly 3) Holley Street Dominator Intake Manifold 4) ARP Headbolts 5) Felpro Gasket Set 6) Total Seal Gapless Rings Bill: $1400+ (this also includes the machine work I'm having done) Quote Link to comment Share on other sites More sharing options...
Tim240z Posted November 23, 2004 Share Posted November 23, 2004 Why the expensive rods....not like you are building a high rpm/compression engine.... Quote Link to comment Share on other sites More sharing options...
zeeboost Posted November 23, 2004 Author Share Posted November 23, 2004 I've always heard that the chevy rods were somewhat weak in stock form. I really can't afford to throw a rod within the next few years, so I figured I'd be on the safe side. Now, I don't have as much experience with Chevy as I do with the Datsun L-Series engines and the Ford small blocks, but that's just what I've always heard about the Chevy rods. My compression ratio should be 10.5:1, and my setup should put out about 400hp and 413 ft/lbs. Do you think the stock chevy rods can handle that? I mostly won't abuse the engine, but I'm sure every once in a while I'll get an urge to gas it. I'd just like a reliable bottom end. Quote Link to comment Share on other sites More sharing options...
Tim240z Posted November 23, 2004 Share Posted November 23, 2004 A good set of basic aftermarket rods will be fine......stay away from the powdered metal ones..... Why are you replacing your intake and carby? Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted November 23, 2004 Share Posted November 23, 2004 First of all stock rods are not weak, besides your not running alot of compression, turning crazy rpms all the time or spraying NOS right? I recommend polishing beams to look for cracks, mag them, install arp bolts, resize them for max crush and let em fly. Turn stock crank 10/10 or 20/20 on the high side and leave it, balance it, it'll work. Pistons look like speed pro hypers, kind of iffy on the wrist pins IMHO. I wouldn't do total seal rings for the street, spend money on heads instead. If it had excessive blowby then total seals won't work even if you hone it. They only work with a fresh, true, round perfectly straight bore, even their own literature states such. Go with a KB hyper, moly rings, get some heads, polish the beams, arp's, arp head studs (clamp better and give a better ring seal if you bore and hone with same). HV oil pump, steel sleeve shaft, block off filter bypass (sounds like it wasn't done before resulting in scoring of journals/bearings). Go with new spings, lifters, retainers, locks, cam, most failures are here anyway. The rest of the normal stuff as well. Check harmonic for elastomer failure, cracks, etc. run new one if needed or upgrade. If you really want it to last, baby it like 'ol grandma, otherwise it's always rolling the dice as even Nascar looses engines now and then and they are 80K apiece! David Quote Link to comment Share on other sites More sharing options...
zeeboost Posted November 23, 2004 Author Share Posted November 23, 2004 Tim240z -- I'm replacing the intake because: most of my miles are highway miles, and in 6th gear I'm usually running in low RPMs, which conflicts with the Victor Jr's powerband of 3,000-8,000 RPMs; dual plane would seem more streetable; I usually don't turn crazy RPMs to use the Victor to it's full advantage; I figured that since I already have the Systemax II setup, I might as well go with the intake that they recommend. I'm not sure where you see that I'm replacing the carb (unless carby stands for something else and I'm too slow to pick up on it ) dr_hunt - My heads currently are aftermarket -- as you can see above or in my sig they are the Holley Systemax II heads (2.02/1.6 -- the usual). the crank has been turned 10/10, and I have a high volume oil pump. The cam/lifters/pushrods have about 4,000 miles on it, if that -- the rest of the valve train has approximately 8,000 miles. Why would you suggest Keith Black over the Speed Pro? I know my cousin does oval track racing and he's constantly turning 7,000 rpms with his Keith Blacks and he hasn't had a problem from them yet, but I was under the impression that Speed Pro was a good brand...something I'm missing out on? Thanks for the suggestions Quote Link to comment Share on other sites More sharing options...
Guest Droopdude Posted November 23, 2004 Share Posted November 23, 2004 Stock rods and the famous chevy "Pink" rods are infact the same thing. The pink rods are magnefluxed and shot peened to reduce stress risers and harden the surface. Quote Link to comment Share on other sites More sharing options...
Guest Droopdude Posted November 23, 2004 Share Posted November 23, 2004 Here is a good article on connecting rods. http://www.grapeaperacing.com/GrapeApeRacing/tech/connectingrods.pdf'>http://www.grapeaperacing.com/GrapeApeRacing/tech/connectingrods.pdf I got this from http://www.grapeaperacing.com/GrapeApeRacing/ One of Grumpyvettes favourite sites. Quote Link to comment Share on other sites More sharing options...
80LS1T Posted November 24, 2004 Share Posted November 24, 2004 I would stay away from the CFDF clutch! I had one in my car and the damn thing chattered like you wouldnt beleive!!!!! If your dead set on it be extremly gental with it for the recommended 500 mile break in period. I have heard this from more than one person about CFDF. I am planning on going with a SPEC stage 2 or 3 with a BILLET steel flywheel. From what I understand the BILLET steel flywheel will hold up a lot more than a stock one when used for drag racing. My car is not a full out race car by any means but I will see track time once done. Guy Quote Link to comment Share on other sites More sharing options...
zeeboost Posted November 24, 2004 Author Share Posted November 24, 2004 Holy crap! That's exactly why I'm replacing mine! it started chattering on me, and I figured maybe it didn't have a good break in. The throwout bearing is seriously FUBARd! I figured I did something wrong, so i was about to buy another one. $550 is quite a bit for a clutch that won't hold up passed 10,000 miles. I guess I need to start looking at other options. Know any good recommendations besides the SPEC stage 2/3, or is that the best way to go? Thanks again for the warning. Quote Link to comment Share on other sites More sharing options...
80LS1T Posted November 24, 2004 Share Posted November 24, 2004 From reading posts on LT1tech.com, I have come to conclusion that the spec stage 2/3 are the most commonly used with success. The CFDF is the most hated clutch set up because it is sooooooooo prone to chattering. Im not sure why though? I will say this, it did hold but then again I never had a chance to run it wil DR on either? This is a quote from the "Thunde Racing Website" Stage 2 - Stage 2 clutches are recommended for mildly upgraded vehicles with a power adder. A segmented Kevlar disk is used on the Stage 2 clutch kits. $440.00 Stage 3 - Stage 3 clutches come with a sprung center disk with pads. The disk pads are a carbon/ceramic combination, rated to 680 horsepower. The ULTIMATE STREET/STRIP CLUTCH! Sharp but smooth engagement with light pedal. $530.00 I have seen these cluthes on EBAY for about $420(stage2)/$470(stage3) If you really are looking for a nice set up you could go with a McCloud twin disc for about $1100. 37-64022-1A-07 McLeod Street Twin Clutch Assembly, 1-1/8 X 26 Spline, Steel Flywheel $1066.99 I have priced out a BILLET flywheel for about $300 and a new clutch/PP set up for about $450ish. So I plan on spending about $800 for a new clutch set up. I have also thought about going with the McCloud set up but I havent read too much on them yet. If they are way less prone to chatter then I might go that way. I just cant stand the clutch chatter. Its one of my petpevs I guess? Either way, stay away from the CFDF or any CF for that matter! Guy Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted November 24, 2004 Share Posted November 24, 2004 zeeboost, I've had three failures of speed pro hypers in circle track engines all wrist pin related. One the wrist pin actualy broke in half between the rod and piston boss on one side, scored that hole and had to sleeve it, bent a rod, causing the adjacent rod to be replaced due to bind and discolor the big end. Also had evidence of the wrist pin severely bending prior to breaking. On two others the wrist pins bent causing binding of the piston and rod creating severe scuffing on the skirts. Speed pro made good on the broken pin, by replacing parts. Big whoopie. On the bent pins, I was told by speed pro that they must of hydraulically locked. This is funny cause both engines were running and were torn down for a freshen only, bad leak down tests, and two pistons in one engine and one in another were scuffed pretty bad and had left aluminum on the cylinder walls which was causing blowby. Both engines had no reports of any problems of any kind, reputable drivers I've known for years, both were bushed rods, in both cases pins were bent .002 to .005. I have no reason to doubt the drivers, neither engine was there for a "comeback catastrophic failure" only a freshen. Since then I don't use speedpro hypers and I haven't had that problem since, so at least in my mind it is my opinion to go with KB's when doing hypers. David Quote Link to comment Share on other sites More sharing options...
zeeboost Posted November 24, 2004 Author Share Posted November 24, 2004 Well, I have the Centerforce SFI flywheel, but I haven't heard any complaints about that one yet. As far as I know, that's the only flywheel I can use with a two-piece block and a t-56 from the LT series engines. That stage 3 clutch sounds pretty good -- I think I'll look at buying that one instead. It should still bolt up to the fly, right? Well, I did post this to get insight and more info on what I should do to buy a stronger bottom end, so I'll go ahead and get the Keith Blacks just for peace of mind. Even though this engine won't be doing any circle tracks, and therefore won't see as much stress, I'd still have that thought in the back of my mind about the wrist pin giving out, so while it's apart, I might as well upgrade the pistons as well. I guess now would be a good time to go with floaters. Thanks again for all of your help. Quote Link to comment Share on other sites More sharing options...
80LS1T Posted November 24, 2004 Share Posted November 24, 2004 I cant see why a spec wouldnt bolt up to that flywheel? The SPEC should have the same bolt pattern as the CF so it should bolt up just fine. I am also running KB pistons in my LT1 and so far so good. I dont have a lot of miles on my engine though since I rebuilt it. I have 175psi compression across the board though on a warm engine. I am running about 10.9-11:1 compression. Guy Quote Link to comment Share on other sites More sharing options...
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