99 Black Bird T/A

iTrader: (4)

Gotcha, thanks for clarification. Always sucks buying a driver to discover is more "project".

Big list of to do to sort car out. The good part is the car will end up being rebuild to suit your desires. There are good long tube set ups that work great, sound good and don't leak.

Magnum's are definitely fun to drive and shift.

FWIW - just a heads up...Sometimes Magnum's are a bit prone to leak from the tail shaft seal. I've had one in my T/A for five years and it's going to have to have the tail shaft seal replaced for the second time. Friend of mine has one in his T/A, he's had two tail shaft seals replaced and his is leaking again. His is also five years old.

500+ whp is doable with an 383 LS1 but its much easier to do that and more with a 427/7 liters. I think a new top end package is needed to hit that goal. Mamo would be the top choice shooting for 500 whp+ with an LS1/ 383 LS1 as his set ups have done that many times.

I hear you on that because free time is very precious.

Clipped

Yes it's aluminum. With cauliflower ear - or at least that's what it looks like to me after the shop welded this apparently infamous ear back on.

I questioned the previous owner and he said the crank did not look stock, H beams and diamond pistons were verified by him. IF I could just stuff a scope in there and see past the windage tray myself I would, but at this point seems like I need a better reason to rip the thing apart then to just verify.

pdxmotorhead

Unsolicited opinion,, Just betting,, the cheapest most productive thing you could do is yank the motor and open it up.
Until then you're guessing on everything. Very few tuners can sort an engine from scratch with unknown parts.

It's cheaper to hand the motor to a builder have it torn down and get to ground zero than it is to chase the unknown.
Last time I had a motor freshened,, it cost me 800 in labor to tear it down, measure it out, sonic check the
block crack check the heads, and let me know the results.
Then it was about 1.2K to put it back together with new rings, plus some light machine work with parts.
he rebated 200 on the tear down since I did the reassembly with him. So 1800 bucks. Last full dyno tune I paid for
on a known combo was about a grand for 1 full day on the wheels.

Any thing found to be below standard or wrong its way cheaper to find it with a micrometer or a dial indicator than on a dyno...

FWIW, my "stock" 5.3 injectors are 34# flex fuels.. The engine is stock and supposed to make factory 300 to 320HP.
It's likely never going to see a dyno, I'm street tuning it. 1 small change at a time. Just doing pulls to 60.
Its an L33 Aluminum block motor. Which IIRC had 24# in the Trucks. My injectors are off a van 5.3 flex fuel iron block.

Every race car ever sold:
1. Fresh motor 1 race weekend # of times thats true... .001

When I read down through the thread you have a laundry list of issues that are because the PO didn't document anything.
When the PO "thinks" is something or "looks like" something it = he doesn't know, but he will give you a good sounding guess.

So I dont know your car, don't know you ,, this is just a 10000 foot fly-by opinion..

Tony @ Mamo Motorsports

Weak heads on a stroker engine show their limitations even worse than they do on OEM engines as the added displacement requires more airflow.

Did you ever post the dyno numbers....I looked quickly but didn't see them.

Suspect the engine might have stock compression and the big cam just obliterated your DCR killing most of the low midrange and then the heads themselves (ported or not) limit the top end just making for a potentially bad combination

I agree with pdxmotorhead.....take some time over the winter to tear into it and see what you have. Consider spending some money for quality aftermarket heads that can properly feed the combo (My MMS 227X heads would be perfect on here) and put a smaller cam in it

If you get good heads, set the static compression ratio right and reduce the size of the cam you will have an explosive and powerful package that will drive great.....you can get close to 500 RWHP even factoring in the auto trans but that was never going to happen with OEM 853 castings ported or not

You need a ported 102 intake as well if your intent on really achieving your goal.....500 at the tire thru an auto is 530 - 540 with a manual trans and while that's entirely possible with good parts and an optimized combination its not remotely possible with what the engine consists of now.

I made 535 at the wheels with my 383 in my C5 back in 2005 but that was using good parts available at the time. My new 227X head smokes the 220 head I ran back then but it was a solid build and the 220 head I ran was a bunch better than any ported OEM head.

This guys journey with his 383 and a couple of cam swaps might be of interest.....you dont necessarily need a big cam to make good power (especially with really good heads).....you need the right cam

https://ls1tech.com/forums/corvette-...-good-bad.html

I think some of the disappointment comes from having unrealistic goals of what your current combination was capable of.....its quite difficult to get close to 500 RWHP with a cathedral headed 383 thru an auto transmission. It requires a solid optimized combo to get there ($$$)

Seems like your not keen on working on the car though and to really turn this around or even just improve it a good bit that is going to be something your likely going to have to consider. Or sell the car to someone else and start with a different project that needs less work

If you do decide to work on it hit me up and we can discuss sone of the items I recommend you upgrade.....to see any noteworthy changes aftermarket clean sheet design heads should be first and foremost on the short list.....you need to ditch the OEM castings

Good luck with the project either way

-Tony

Clipped

You have mail sir.

Thank you for taking the time to reply.

Clipped

I understand the best way to get a look at a steak, but I took the butchers word...... Will take pics again in the future when I have the thing apart.