Trading my 5.3 vortec tmro for an lt1 block bored 60 over with srp forged pistons & rods. Crank. & 510 lift hydraulic camshaft . Getting complete motor without heads or intake.. But i have lt1 heads.. Im going to try to get all i can with it but i have a lt1 .40 over (385) lt4 intake & afr 210cc heads, 58mm throttle body ect making 410hp. I would like ur guys input on what to do to this spare motor building it wise to make 5-600 hp. Port the lt1 heads ? Reuse the afr heads. ? All replies would be appreciated thanks.

 

Why doesn't your current engine meet your goals? That would be my first question. I would look at you cam selection based on your heads and bottom end. If you're saying it makes 410 at the wheels, then you are making that 5-600 at the crank. If you want to make that at the tires, you're going to need a very good valvetrain, a solid roller, and a lot of $$$ in buying a light roating assembly. If you're not willing to go that far, sell the 5.3 or .060 over block and buy a nitrous kit. I've done the research and talked with the engine builders of the quickest stock cube LS1, and in order to make 600 whp with an sbc takes a good chunk of change. You're better off keeping that 5.3 and going to town, it'll save you a bunch of money in the long run. It's a lot easier to hit that number with an LSx engine.

If you already have a forged bottom end, spray it and have fun.

But that's my $.02

 

Turbo that 5.3!

 

Might want to review the 385" build to figure out what is wrong that it makes no power, so you don't repeat it on your next build. It's always to learn from previous projects to improve the next.
Seems like too much attention given to valve lift (which means VERY little!) and not enough to quality and acuracy of cylinder wall boring & honing, fit & finish of piston ring lands and ring selection. Ditto start up & ring seating & break-in.

What do you know about the machinist that bored and honed the block?
I have had a couple of customers that race their LT1s at the track regularly, and I tuned on my dyno. Both cars were 100,000 mile factory short block F body cars. Heads, cams, headers, etc. They rebuilt them, using a local shop & guy that bracket races locally. Bored .030" over. Both cars slowed down. They both brought them back to me for "re-tuning" (should have been no need, nothing else was changed.) one car was down 18 rwhp, other one was down 30!
I would never buy one when I didn't know more about it. A lot of you guys here are looking for power in the wrong places.

 

Not to derail this thread but what do you think happened to cause power loss? Incorrect ring gap? etc etc?

 

Poor break in procedures and machining will cause that kind of power loss. Lots Of stuff to consider in machining like ptw clearance types of rings used, type of piston used, the ability to machine the bores in a way to show exact torsion the block will be under when bolted to the heads and such.
To op
I agree with ed, you should be making a lot more power. You either should do research on engine building theory or let someone, who has built an engine that is comparable to yours that makes great power, do the building for you. Lots of people here can help you but you will definitely need an open mind and be able to swallow your pride.

 

OK.........410 hp at the crank or 410 hp to the wheels?

KW

 

if that's 410 hp to the wheels on a lt1 383 that's respectable..

my 383 was making 416hp to wheels..

600 rwhp on a na 383 lt1 will take really deep pockets..

 

Stick head & cam cars typically make more than that, of course that's if the heads are good. L.E. & AI head cars do it all the time.
But, I have seen 383"s that would not make 300. Not all "built" short blocks make as much as factory short blocks. Many don't realize the factory piston & ring set up is better than what they are putting in their builds. Narrower lower tension rings and better machined & finished ring grooves. Stiff, heavy rebuilder rings cost power.

Not all (most) machine shops can deliver round enough, straight enough cylinder walls with the correct surface finish. Takes more than a torque plate and an old Sunnun CK10 hone. The best deal right now is a Rottler Diamond hone. Absolutely makes more power. Improved ring seal is worth a ton more power than more valve lift.

 

Pardon me for interrupting guys,
Ed , what brand of rings & pistons would
you recommend for a rebuild? N/a no nitrous.

 

Hard to beat what came in these engines, Mahle. J.E. Piston's SRP brand isn't bad. I have not seen many needing re-bored anyway. Honed and new rings, not the cheapest rebuilder stuff you can find. Speed Pro is a good one. That stuff is fine for a budget build. Personally, I would use their low tension oil ring.
If you are trying to build a fast one, CP or Bill Miller are hard to beat. My long time Pro Stock racer friend Mike Edwards uses CP in his race car. That is also what is in mine right now. Piston rings, pretty much the standard is Total Seal, but nobody I know uses their gapless ring.

 

Hard to beat what came in these engines, Mahle. J.E. Piston's SRP brand isn't bad. I have not seen many needing re-bored anyway. Honed and new rings, not the cheapest rebuilder stuff you can find. Speed Pro is a good one. That stuff is fine for a budget build. Personally, I would use their low tension oil ring.
If you are trying to build a fast one, CP or Bill Miller are hard to beat. My long time Pro Stock racer friend Mike Edwards uses CP in his race car. That is also what is in mine right now. Piston rings, pretty much the standard is Total Seal, but nobody I know uses their gapless ring.
Do NOT use a high volume oil pump! One of the dumbest things I see done.

 

Don't know how that showed up twice. LOL

 

^^^^ Now that's the stuff I want to know about when I get to building my motor finally. I want it done right the first time and not be some hacked up junk that only makes 350 hp.

 

My car makes 410 hp to the wheels! It sounds low. As we all say it should push more. But car is super fast. Gets 6mpg & is just a toy. As for nos. i got 2 bottles. Nos & nx. Its set up for bos but motor has never been sprayed as its only got 2k on rebuild. & just changed the oil. From what iv heard people say on here before is a dyno is just a benchmark & not to get discouraged. (Nvr had to track yet) as for keeping my 5.3 ? How come. Would that work in an 94 z? I hadda 98 z28 roller car is what i have that motor for. I was gunna through that in there as i couldent afford ls1. Or turbo for that matter. Lol. But have a much better car now.

 

The 5.3 will fit using parts from the 98-02 cars. Take it to the track as is and post up some times and mph. That will be a better indicator as to power. Something sounds off, but its hard to tell with general info.

 

How can you know it's "super fast" if you have never been to the track?

 

Thanks for the advice Ed!

 

lt4 intake does not work with lt1 heads

 

LT4 intake will bolt up and work with AFR210's and 227's as well.