Hi, im not real sure where the right section to ask this question would be. I have a 98 trans am, car was a "cam only" setup for many years. A couple years ago I scattered the stock bottom end on a 250 pill. Car has been sitting for a while, and I am thinking about getting it back out. I have another short block for the car, it's a 02 LS1. I also have a set of Advanced Induction 243 heads, and a TREX cam shaft sitting on the shelf. A friend of mine offered to sell me his 5.3 for a decent price. It is a iron block, all freshened up by a reputable local machine shop. It has a stock crank that has been polished, stock rods, stock flat top pistons, but all new bearings through out, and rings that are supposed to be better with nitrous, I haven't really got into many details with him yet. I have a plate setup on my car, and want to spray around 150-200 when I race the car. My question is, am I better off trying to hit my stock 02 LS1 short block with 200, or the 5.3? Also would the 5.3 make less power than the LS1 with the same top end (243s, TREX, Fast 102) on both? Thanks!


-Rod

 

as for the power question the 5.7 reacts better to a cam set up like that. but with that amount of spray i personally would trust the 5.3 over the ls1. especially since the 5.3 is freshened up with a good set of rings id go with the 5.3 if i were you

 

theyll make similar power naturally aspirated

 

I would go with a 5.3. I wouldn't be comfortable with more than 150 on a stock bottom end LS1. On the other hand, we have sprayed 200-250 through a "stock" 5.3 for awhile now. (Cam only.)

-Garrett

 

I think I'm going to go with the 5.3...I just hope it isn't too much of a dog NA. But at least it's all fresh with good rings. And ARP rod bolts/head studs.

 

The LS1 is always going to make more power if you were to mod them the same. I would go that route.

 

guess I need to start saving for a bottom end lol

 

LOL. I'm not saying you can't do it, we have sprayed 200 on a completely stock C5 vette, however, I have seen it done alot more on a 5.3 setup without any issues. Just seems stock for stock, a 5.3 will handle more nitrous and/or boost stock for stock.

Thanks,
Garrett

 

I agree with what Garrett@Nitrous Express is saying... Stock vs Stock I've seen a 5.3 go farther but just in longevity. An LS1 will dominate in power in NA form with the same mods. The 5.3 especially the GEN IV motors seem to be stronger for longer. The tune up is going to determine how long either combo stays together.

My personal combo is a LS1 SBE and on a 125 shot, going 6.47@106.8 on a 1.43 60'. It will see a 150 and a 200 shot non-progressed. As I plan to take it as far as I can. Not looking to break any records, just set some good personal bests.

Also take into consideration, if any money is going to be spent on this build. There's no replacement for displacement. So take it for what it's worth, but I'd rather have a forged nitrous built 5.7 than the same in a 5.3.