555 BBC twin turbo update
#4
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Re: 555 BBC twin turbo update
That's wicked.
I thought I heard turbos in the video. Where are they??
I thought I heard turbos in the video. Where are they??
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85Z28NOS (03-12-2021)
#7
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Re: 555 BBC twin turbo update
Oh my gosh!
That's going to mess with your hairdo.
That's going to mess with your hairdo.
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Re: 555 BBC twin turbo update
So...AWESOME! True duals? What kind of mufflers? Sounds great!
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IROCThe5.7L (01-01-2020)
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Re: 555 BBC twin turbo update
I saw these videos on your youtube channel in my subscriptions and was amazed. Killer work! So awesome. what a wild project.
- what do you plan on doing for a tire combination. From the video it looks liek you have a Nitto 555R on there now.. has that been holding up for your previous 1100hp or not really?
- what do you plan on doing for a tire combination. From the video it looks liek you have a Nitto 555R on there now.. has that been holding up for your previous 1100hp or not really?
#16
Re: 555 BBC twin turbo update
Its a mickey thompson on these 19’s. I might end up getting rid of them and they are almost wore out anyway. They hold up to about 800 whp pretty well. I have my 15’s with good tire for when i want to play at 1000-1200 but thats all they will hold too on the street. Im not sure what this car will do. Its got alot more weight in the rear so it may help it out some
#18
Re: 555 BBC twin turbo update
decided to test it to make sure things are working. So far seems good. Did a quick 2nd gear hit. Ran to 6400 rpm. Spool is decent, alittle lag but smooth. Not bad for big 1.32 ar t6 housings. Top end is insanely strong. Only 4.5 psi and it feels like its as quick as my sbc car was on 15
now to finish the wiring in the interior and coat the pipes, start working on the rear enclosure
#20
Re: 555 BBC twin turbo update
Phone doesnt do it justice, definitely loud but not terrible. Once its covered, insulated abit and carpet back in it should be great. Just hope the snails still can breathe well from underneath but the top wont be totally sealed.
#22
Re: 555 BBC twin turbo update
It should be good by then. But i dont plan to run it much without the cage.i’ll run it to the 1/8 or 330 for abit to dial in the launch and see how car feels. I wont do a full pass i dont think unless i can get atleast the 10 pt in. I have heard ihra tracks treat 10-12 pt cages to 7.50 and not 8.50 like nhra but not sure how true that is lol. But i would feel better going for a high 7 with a 10 pt so the track wont be as worried
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Re: 555 BBC twin turbo update
Oh man that thing is wild!! Sick ride for sure
#25
Re: 555 BBC twin turbo update
12 psi early tuning on pump gas.
now back on e85, 80% now. Had it up to 16 psi but boost is falling off to 14. At the limit if traction. One pull seemed to hook 3rd gear to 145 mph another it was skating, grabbing and Breaking loose. Gotta get on the dyno next
interior is back in ready for the street
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zoidberg355 (08-07-2022)
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Re: 555 BBC twin turbo update
I wouldn't be intimidated Orr. I'd race ya.
It'd only take a 2000 HP hit of nitrous.
It'd only take a 2000 HP hit of nitrous.
Last edited by skinny z; 05-08-2020 at 05:30 PM. Reason: Political correctness.
#36
Re: 555 BBC twin turbo update
Just updating...lost a lifter and wiped out a cam lobe late last summer. Had to yank motor and clean it out, replace bearings. Decided to put in a higher volume oil pump since i didnt like my pressure from before.
got a new cam and lifters from my old cam guy, he did my 383 and second 401” turbo cam. Discussed with him and he had some ideas to try with some interesting new tech. Cam is alittle shorter in duration now, abit less lift. Incredible thing is it uses a conical valvespring with seat pressure that i wouldnt run most hyd rollers on lol but it seems to work so far. Should be awesome for rocker arm life and lifter life on the street
after a few months of waiting for back ordered valvetrain parts i found a replacement thru PAC and got them. Got motor in a few weeks ago and running this week. First drive on same tune as before looks promising. Motor needs a lot more fuel, 10-12% midrange and 7-9% up top. Pulled nice to 6780 so far. Limiter is to be set to 7100. Was only on 7.5 psi but seems to spool slightly sooner and rpm trace was good. We shall see.
got a new cam and lifters from my old cam guy, he did my 383 and second 401” turbo cam. Discussed with him and he had some ideas to try with some interesting new tech. Cam is alittle shorter in duration now, abit less lift. Incredible thing is it uses a conical valvespring with seat pressure that i wouldnt run most hyd rollers on lol but it seems to work so far. Should be awesome for rocker arm life and lifter life on the street
after a few months of waiting for back ordered valvetrain parts i found a replacement thru PAC and got them. Got motor in a few weeks ago and running this week. First drive on same tune as before looks promising. Motor needs a lot more fuel, 10-12% midrange and 7-9% up top. Pulled nice to 6780 so far. Limiter is to be set to 7100. Was only on 7.5 psi but seems to spool slightly sooner and rpm trace was good. We shall see.
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Re: 555 BBC twin turbo update
What do you think caused the need for more fuel? Did the new cam pick up air flow, even though it's smaller? 10% more fuel isn't a small change, in terms of Lbs per Hour.
#40
Re: 555 BBC twin turbo update
I may have spoken to soon. That was on a lower boost hit. On more boost it doesnt seem to need alot more fuel up top, but some more in mid range. I guess maybe my original map may be lacking in fuel at the lower boost stuff but i could swear it was well tuned there at one time lol
duration being shorter and spooling alittle bit sooner is my guess for more fuel.
duration being shorter and spooling alittle bit sooner is my guess for more fuel.
#41
Re: 555 BBC twin turbo update
Had a plug wire off on a test the other day. Car seemed lazier and slower to spool but was hard to tell lol idk but with that much power being off 1 cyl doesnt always seem noticeable i guess.
after reconnecting plug wire it spooled much better, as i also leaned it out in the spool region, it seemed to help. Power feels ridiculous which is good but idk how much fuel changed from last cam logs. It seems to be similar so at the very least, going smaller in cam didnt hurt output but driving off boost feels alot better and did seem to increase in fuel demand some
after reconnecting plug wire it spooled much better, as i also leaned it out in the spool region, it seemed to help. Power feels ridiculous which is good but idk how much fuel changed from last cam logs. It seems to be similar so at the very least, going smaller in cam didnt hurt output but driving off boost feels alot better and did seem to increase in fuel demand some
#42
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Re: 555 BBC twin turbo update
awesome
I love following this build what a monster. More videos for youtube !
I love following this build what a monster. More videos for youtube !
#43
Re: 555 BBC twin turbo update
been messing with a rolling two step. Just ground activating holley rev limit 2. Tried yanking some timing around the same rpm to get some heat into it. Does seem to help alot in getting response up.
my fam came to visit and my little cousins are big fans of the car so I took them for a ride
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#44
Re: 555 BBC twin turbo update
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my buddy said he had some free time monday so i could use the dyno. Made 9 pulls and working up tune with new cam. Initially power was way down but combo wanted alot more timing than before so it just behaves different or my timing offset in the crank trigger needs checked again. Either way i think i ended up 4 deg more and picked up almost 100 whp at 17 psi. Made 1441 there. Previous was 1400 on 15 so cam is alittle smaller and it was hotter out, and slightly smaller exhaust housings. So power is close to same maybe slighly lower. There may be 10-20 in simple air fuel and another half deg or two lol but wasnt goin to stay there. Worked up to 23 psi and made 1602 before end of day. Discovered some issues with bank to bank fueling differences, almost a point richer on driver side so thats hurting. Gotta check injectors and plug gaps etc
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#45
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Re: 555 BBC twin turbo update
1600, holy crap. I was a little scared with all of ~260 horse on the road course, I can't imagine that much
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Re: 555 BBC twin turbo update
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my buddy said he had some free time monday so i could use the dyno. Made 9 pulls and working up tune with new cam. Initially power was way down but combo wanted alot more timing than before so it just behaves different or my timing offset in the crank trigger needs checked again. Either way i think i ended up 4 deg more and picked up almost 100 whp at 17 psi. Made 1441 there. Previous was 1400 on 15 so cam is alittle smaller and it was hotter out, and slightly smaller exhaust housings. So power is close to same maybe slighly lower. There may be 10-20 in simple air fuel and another half deg or two lol but wasnt goin to stay there. Worked up to 23 psi and made 1602 before end of day. Discovered some issues with bank to bank fueling differences, almost a point richer on driver side so thats hurting. Gotta check injectors and plug gaps etc
Things were almost always going great... except whenever tuning needed to be done on the Chassis-Dynamometer.
For many years, I had to struggle trying to keep this kind of Power from spinning the Tires on my Chassis-Dynamometer...
What a pain!
Because of this, I tried to do as much tuning as possible on the Engine-Dyno... however this only gets you so far with the tune.
Eventually tuning needs to be finished at the Track or on the Chassis-Dyno.
About 2 years ago, I was able to replace the Chassis-Dyno with a Hub-Dyno/ Diff-Dyno.
I LOVE this Hub-Dyno!!! Traction issues on the Chassis-Dyno... Never again!
The Hub-Dyno is the way to go!!!
If any of you guys are unable to lay all of the power down, that your vehicle is making...
Find yourself a Shop with a Hub-Dyno/ Diff-Dyno!
You are going to love it!
... and especially the numbers from the Dyno results!!!
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#49
Re: 555 BBC twin turbo update
For many years, I had to struggle trying to keep this kind of Power from spinning the Tires on my Chassis-Dynamometer...
What a pain!
Because of this, I tried to do as much tuning as possible on the Engine-Dyno... however this only gets you so far with the tune.
Eventually tuning needs to be finished at the Track or on the Chassis-Dyno.
What a pain!
Because of this, I tried to do as much tuning as possible on the Engine-Dyno... however this only gets you so far with the tune.
Eventually tuning needs to be finished at the Track or on the Chassis-Dyno.
i would love to get on a hub dyno. This dyno is inertia based and will not load the car at all. I have issues getting boost so i have to put car on the rolling twostep at 4000 for a couple seconds to build 4-6 psi before going
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vorteciroc (06-10-2021)
#50
Re: 555 BBC twin turbo update
Got a new set of radials. Been on my old set and they are hard and dont work well. Tried them at the track before and didnt work out but the track did get a new surface and prep hasnt been great
with the new set it seemed to hook better down track. Trying to get suspension working with these new shocks, double adjustable so lots of settings.
I tried no boost first gear leave, a 1 psi leave and a 2nd gear leave on 6 psi. All were lazy 1.42-1.48 60’s. Second gear leave was quicker to full boost and ran the best 1/8 but i think the best potential will come once i get first gear to work. Too much boost it spun, not enough it was lazy to spool
car showing some potential. 2nd gear leave went 5.48 at 138 on roughly 18 psi. The other first gear leaves went 5.70 at 141 on 20-21 psi and then 5.57 at 139 on 22 psi but hit limiter on 1-2 shift. Previous best with the sbc was 5.32 at 136 i believe so im already well over that mph wise and et will best it once i drop 60’
car is squatting a bit so i need to play with bar angle, need to get more adjustment in my lca brackets. Gonna buy trz mounts which will lower it another inch. Gotta add some preload in the roll bar and it should come around
with the new set it seemed to hook better down track. Trying to get suspension working with these new shocks, double adjustable so lots of settings.
I tried no boost first gear leave, a 1 psi leave and a 2nd gear leave on 6 psi. All were lazy 1.42-1.48 60’s. Second gear leave was quicker to full boost and ran the best 1/8 but i think the best potential will come once i get first gear to work. Too much boost it spun, not enough it was lazy to spool
car showing some potential. 2nd gear leave went 5.48 at 138 on roughly 18 psi. The other first gear leaves went 5.70 at 141 on 20-21 psi and then 5.57 at 139 on 22 psi but hit limiter on 1-2 shift. Previous best with the sbc was 5.32 at 136 i believe so im already well over that mph wise and et will best it once i drop 60’
car is squatting a bit so i need to play with bar angle, need to get more adjustment in my lca brackets. Gonna buy trz mounts which will lower it another inch. Gotta add some preload in the roll bar and it should come around
Last edited by Orr89RocZ; 06-21-2021 at 07:18 AM.