i was thinking of going with the speed pro forged kit in summit for like 575 bucks any other advice and can i fix all this without pulling the motor or what would be the easiest way to fix my problem. any advice is welcome, thanks
joe

 

you guys gotta have some kind of advice, 25 views and not one post, comment, anything, i need a lil help here.

 

I think I speak for most everyone when I say pull the motor have all of the correct machoine work done and checked. Otherwise you aree gambling on throwing all that money away. You motor may need to be bored or atleast honed. Your talking about a motor that turns some decent RPMs and makes some good HP. You will not be able to skimp out of it. I once built a motor and skimped on having the block checked just had it honed and threw in new parts. Guess what a crack in the lifter galley dumped some antifreeze in the oil about half way to where we were headed and that took out the whole lower end. I had my entire racecar motor done by a machine shop here in town and I assembled it. turn 4200- 6200 all day long for 20 or 30 laps at a time never missed abeat all season.

 

Do a stroker

 

Not to pick nits, but first off, I dont believe you can "throw a rod bearing." You usually either spin a bearing or throw a rod.

So, my question is, how do you know you've got a spun bearing? Just loud ticking? Have you had low oil pressure recently?

It sounds like your diagnosis is just a hunch at this point. I would make sure you're not rebuilding the engine for something silly like an exhaust leak, loose spark plug, or collapsed lifter. That is, unless you want an excuse for a buildup.


And yes, I would agree with race24x. If you want to do a rebuild, you'll have to pull the motor, and do it the right way. If you try to save money by skimping on the rebuild, you might end up spending considerably more down the road when you have to do it twice.

 

thanks for pointing out the typo and ya your right i meant to say, spun a rod bearing.

so let me tell ya what happened, put the hotcam in about a month ago runnin awesome, got the obd1 conv. its nice.

took it to the track and thanks to the obd1 conversion i hit the rev limiter on the 1-2 shift during real hard launchs, pcm4less said its just something in the obd1 tuning that you have to live with i guess, only happens on real good launches. but im pretty sure i over revved this **** out of my engine.

so after that i got a what sounded like a real loose RR knock but a little deeper in the engine. so stopped racing took it back to the shop popped the valve covers off and all the RR's are still tight and adjusted properly.

i havent pulled the intake yet to check the lifters and ill check the pushrods then also to make sure none are bent.

i did pull the dipstick out though and found a small metal flake on the end. i still have oil pressure tough and the car still runs super strong, no misses no backfires, during the last run when the knock started i still ran a mid 13 and my best is a 13.1 so i havent lost much power. just picked up an intermittent knock deep in and found some metal flakes.

im gonna tear it down before i start buying parts but just thought i would assk opinions

joe

 

It really does sound like you have started to spin a rod bearing especially if the sound is right about when you rev it up and let off the gas (not alot just rev it to 2500 or so) and you can hear it about when there is no load on the engine. Kind of in between revving up and the engine coming back down. the only real way to tell before substantial engine damage is to pull it apart. I cant tell you if you can pull the oil pan without taking out the motor but it would be a good place to start pull rod bearings one by one to see how they look.

 

Yes, the oil pan can come out of the bottom w/o the engine having to come out. I have my oil pan out now checking all of my rod bearings as we speak. Good luck!

 

if i have a bad rod bearing, can i just replace the bearings or do i have to get oversized bearings and turn the crank., what are the chances that i scarred the crank during all this. and would it be better to just get a used LT1 crank and throw it in with stock size bearing or what. im never planning on goin all out with this car, i might put a set of lt4 heads and intake on someday but thats as fast as i want it to be so ill never push over 500 hp

and how do i get the oil pan off without pullin it, i have LT's so theres plenty of clearence, but do i need to drop the kmember and how long does that take, any tips

 

you have to check all the clearances and go from there. if the crank is scared up, it should be ok, my cylinder walls look good so i got lucky. if it is scratched up, yes, you will have to get it turned and honed probably. you will have to drain ur oil to get the be able to see the crank and check the bearings.. also you will have to take ur motor mount bolts out so you can crank up the engine to get the oil pan to drop. The k-member did not have to come down when i pulled my oil pan. just make sure you check all the bearings and plan on replacing all of them since you have everything off anyways


-Mike

 

welp, drained the oil and found it filled with metal fillings and had a silver tint and swirls so i started pullin it yesterday, got it out today and tore it all down. spun rod bearings 7 & 8, they are fused together and too the crank. just thought i would post and let everyone know what was goin on, thanks for all the help everybody
joe

 

So do you have to get the cranked turned? What kind of noise was the car making that lead you to believe it was the spun bearing?



-Mike

 

it was a clunking from inside that sounded like a loose RR, gettting a new crank