98blackgtinsc

ok guys, the pistons are NEW!!!! so thats a good thing, i think i might be better off going for forged H-beams with 10,000 miles for the same price, actually less than new stock rods. IMO thats worth it. again im only making 350-400HP!!! not even close to any of the number you are talking about.

bransdaman78, thanks for the advice, unfortunately i dont have 1400 to blow, im rebuilding the motor in my garage, and i need to put it in my car sometime soon, so i need the best parts i can get as soon as possible as cheap as possible, ha, i know, horribly unrealistic, but i feel as though h-beams for as cheap as i can get them are worth it. the crank is a good i idea though, thanks.

godamgt00, if that question was for me, i have two blown pistons, it is the pistons that are gone, not the pins.

thanks for all the help guys.

98blackgtinsc

one more question... if i get my block bored .020 over, will the stock 03 pistons still work, i've heard they're so tight in the cylinder that it is better if it's bored, and i've also heard that they wont work because they'll be too small. them being too small seems to be more logical but i have no idea, anyone who knows anything about this, any info would be great thanks.

bransdaman78

well realistically get your block bored over isnt going to really help you... I wouldnt waste my money with that, however the piston size on the cobra should be identical to the GT, the cobra piston swap will also lower your compression... but aftermarket forged will also, basically just do a charger and be done with it.. the gain from the bore will comparativly insignifcant, escpically since you are not going to max your motor out.

bransdaman78

also the over bore will weaken your block if ever want to get crazy with the power... either way I just dont think its a good / worth while idea

GodAmGT00

Partly true.. If you blew out 2 pistons, personally, I'd have the block bored, cleaned and O-ringed (if possible on the 4.6).. Boring over doesn't weaken the block as much as the sleeves.. Even then, we're talking some serious power, or poor tuning..

I was asking the question about Wrist pins/piston strength to the general audience... I'm not very familiar w/ the internals of Cobras, besides the general make up, and what not...

I suppose you could just get a Cylinder hone and just clean up the walls, but if I'm investing my money, I'm going to get as much out of it as I can...


JT

code3GT

Here we go again.....If you don't know, PLEASE don't answer. 281 bored .020 over is NOT a 294 or 295...it's 283 cubic inch.

bransdaman78

yea, but consider the added cost and risk of over boring.. and the measley power gain... you money is better spent on high strength internals and a blower that will take you there... you will get all you ever wanted out of the 4.6 with f/I so the extra or 20 or 40 hp that boring adds is really insignificant... the internals and head work will make your 2v hold 600-1000 hp depending on F/I choice and what not... so whats the difference between 750 crank hp and 800 crank hp... not much for a street car, and often a little less power (in the high power range) will equal a faster street car.

code3GT

Yup, .020 overbore will in no way boost performance. It's basically just to clean up the cylinders.

GodAmGT00

Well, you won't get even 10hp from boring it over .020, or .030.. In fact, you'd be lucky to get 5hp.. The idea though, is to rid the cylinder walls of the outer layer, that's seen the excessive heat, and abuse.. The good idea of boring also means you can get better seated rings, which are ULTRA important if you're boosting/gassing.. W/ just a regularly honed wall, you may still have small gouges, or metal fatigue, not as visible, which could create a bigger problem down the road..

Also, I guess what I should have said was, if I'm going to build an engine, I'm going to take my time, and buy the right parts, instead of trying to bargain hunt for odds and ends. This solves a few major issues, such as the condition of parts being used, and I can take my time, and not drop $3,000 at a time on parts...


JT

bransdaman78

yea I agree with that, but I have hardly seen a need to do more than just a hone on a 4.6 street car that hasnt been previously sprayed or force fed... I would say that if it is properly honed that worry shouldnt be too much of a factor, again mush less so than buying better new internals