87 octane vs 91 octane

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swathdiver

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That's how we did the turbo motors, lots of timing down low, lean to spin up the turbo and rich on top and pull timing slightly as needed. Like you said, we didn't bother with a 1 degree knock while shifting.
 

Scottydoggs

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yeah a blip for a 0.5 of a second aint hurting nothing. its when its stays and keeps building.

then your ******* uncle chip shows up and ruins the party.

there he is. lol heres the kicker, i was already building the new engine for the car. plan was to have a running spare. yeah right. it knew wtf was up, and like a scorn woman, she blew up on me.

let me tell ya, when you chip a piston, you know asap you just hurt the hell out your engine. made some damn horrid sounds at 6,000 rpm till that chip got chewed up and passed the valve. ate the spark plug and then started to misfire really bad. never thought you could hear it being eaten up lol

001_zps6vksnwbu.jpg

ate that valve up too. it held no air pressure when i was taking my valve springs off it. straight hiss out the exhaust port lol

003_zpshaokf3va.jpg

the new woman was just to pretty for her lol she bailed....

001_zps0c1mkak3.jpg
 

swathdiver

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On my '79 and later my '85, melted pistons on both, they sounded like birds chirping. The material between the rings on the sides fell away like those chips. Never had a chip though, just plain melted them! What a lesson in fuel pressure! LOL

Love those old Buick motors!
 

Scottydoggs

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ouch, melted is pretty damn bad. guessing you didnt have a wideband? so needed to tune properly. even more so if boosted.

adding meth i ending up pulling 3% fuel from the maf 7000 to 12500 hertz, and another 1 or so % from 4000 to 7000. she hits high 11's then dips back down to low 12's on the wb when she's wound up good.

meth kit is progressive, so it starts at 4 psi and max at 8 psi, i make 12 or so max psi, depending on how cold it is out side. get a -5 degree out side temp and im hitting 14 psi no problem, gods intercooler is king.

i wish there were words for the sounds my engine made lol it was like a hi pitched crunching ringing sound, that lasted way to long, was heard after i let off the gas for a bit too.
 

swathdiver

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ouch, melted is pretty damn bad. guessing you didnt have a wideband?

Whatsa wideband? This was in the 1980s and early 1990s. It wasn't until '92 or so where we had the ability to hook laptops up to the newer Grand Nationals and do more specialized tuning. My buddies blew a lot of engines that way. I stayed with mild chips and pulled power through careful selection of parts and headwork and massaging what was there already and turbos. The biggest problem people run into now and then was making things too big. In my speed shop, I made more money taking all the quackery off the cars then selling parts.
 

Tonyrodz

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yeah a blip for a 0.5 of a second aint hurting nothing. its when its stays and keeps building.

then your ******* uncle chip shows up and ruins the party.

there he is. lol heres the kicker, i was already building the new engine for the car. plan was to have a running spare. yeah right. it knew wtf was up, and like a scorn woman, she blew up on me.

let me tell ya, when you chip a piston, you know asap you just hurt the hell out your engine. made some damn horrid sounds at 6,000 rpm till that chip got chewed up and passed the valve. ate the spark plug and then started to misfire really bad. never thought you could hear it being eaten up lol

001_zps6vksnwbu.jpg

ate that valve up too. it held no air pressure when i was taking my valve springs off it. straight hiss out the exhaust port lol

003_zpshaokf3va.jpg

the new woman was just to pretty for her lol she bailed....

001_zps0c1mkak3.jpg
I have Fel Pro .030 pistons from my GN motor. Would they fit in your motor? I only have 5 tho lol. Would any GN internals fit your 3.8? I wouldn't mind running you, just for the fun of it.
 

Scottydoggs

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I have Fel Pro .030 pistons from my GN motor. Would they fit in your motor? I only have 5 tho lol. Would any GN internals fit your 3.8? I wouldn't mind running you, just for the fun of it.


nope, wont fit. thats a gen one 3800. ive got a na block in mine now too. so hi comp and boost. the stock sc engine is a L67 with 8.1 comp where the na block is 10.1.

ive been trying to get back to the track, with e town being shut down, island is the closest track really. they run friday night test and tune, and most sundays are test and tune.

damn regal just started making some odd noises. seems like a bad axle or hub. its not bad enough to pin point it yet, everything feels tight still.

http://www.islanddragway.com/schedule/

i was shooting to go fri night but with this new noise that showed up yesterday, im kinda hoping its rained out lol shooting for next week for sure after a repair is made.

sadly, ive been trying to go since march, the few times i was able to go, it rained. working 6 days a week blows.

ill pm ya when im fixed up and able to go/

i got a friend whos got a coyote stang with stage 3 stuff bolted on and tuned, stock he was running 12's spinning 3 gears lol it was hilarious to see him get trashed off the line, then he shoots past them like they are standing still by the 1/8 lmao. i need to give him a call, see if hes got some dr's or not yet. cause hes gonna kill st tires for real now. hes always up for racing tho. so thats a third car to play with if he comes as well.
 

Tonyrodz

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My powermaster is shot, so the brakes suck. I still gotta do a swap over to vacuum. My boost is only around 15 lbs. I won't touch it, with my luck I'll blow it up. I know you gotta raise fuel along with boost. I know it could handle 18 lbs.
 

Scottydoggs

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My powermaster is shot, so the brakes suck. I still gotta do a swap over to vacuum. My boost is only around 15 lbs. I won't touch it, with my luck I'll blow it up. I know you gotta raise fuel along with boost. I know it could handle 18 lbs.


if i had a turbo,,,oh boy..... they take 15 psi like nothing, ive seen builds that were running 25 psi. but they break stuff, like 5,000 dollar built trannys. they end up being 550 hp. at 15 psi you looking at 400+ easy, with a cam at minimum for supporting mods. even stock cam they can get up there.

what ive seen over the years with the fwd crap. if you push it past the 350 mark your risk breaking stuff way to easy. so im happy with my 300 hp.

i got a semi built tranny, everything a built one would have, minus hard parts, was just not in the budget. really wish i had the hardened input shaft at min.
 

swathdiver

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My powermaster is shot, so the brakes suck. I still gotta do a swap over to vacuum. My boost is only around 15 lbs. I won't touch it, with my luck I'll blow it up. I know you gotta raise fuel along with boost. I know it could handle 18 lbs.

Are powermasters not available anymore? The '84s and early '85s had hydroboost like the diesel G-bodies.

I used to run 18-20 psi with a 237 regulator, stock pump and injectors on pump gas with a bottle of 104+ octane booster or Sunoco unleaded race gas when available. The motors were designed to run indefinitely at 20 psi but run them at 24 psi in 3rd gear and you'll lift the heads off the deck. A 24 psi swing was ok in 1st if it settled back to 18-20 psi. We used air compressor dials mounted in the ashtray to control the boost. That's how I melted a couple of pistons racing an RX-7, kept turning up the boost to beat him, his whole motor blew up and I melted a piston and drove it home sounding like a bird chirping for sixty miles.
 

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