6266 bb anyone,or just me?
- Thread starter earcher1
- Start date
I ran a 6265 with an 17 blade and it was the fastest spooling turbo that flowed over 70lbs/min I ever tried. It spooled faster than the 60-1. 5 to 28psi in under one second. I'd expect the 6266 to spool the same. Mine was a journal cartridge too.
NyBlankets
Active Member
- Joined
- Mar 17, 2003
Whens it going on Ed?
its already on
C
coach
Guest
With it being BB, it's going to be lower then a journal bearing. I would put it in the 3000 range, but if you ask Dusty Bradford...you will get your exact answer.
Is your motor stock stroke or a 249 stroker or bigger? This also plays into stall for the turbo. My 66 on a stock stroke needs a 3500 or so and with a stroker, it only needs a 3200. Add BB and it goes down another couple hundred RPM's. PTE has a recommended stall chart for each turbo too, but Dusty is the man!
Coach
Is your motor stock stroke or a 249 stroker or bigger? This also plays into stall for the turbo. My 66 on a stock stroke needs a 3500 or so and with a stroker, it only needs a 3200. Add BB and it goes down another couple hundred RPM's. PTE has a recommended stall chart for each turbo too, but Dusty is the man!
Coach
coach said:
Chip cars with no adjustability down low almost never spool as fast as cars with adjustable fuel tables. Just eliminating the factory MAFS when over 500hp has a significant effect on spool. The fuel used plays a big role also. Even on a 93 octane tune my stock stroke only needed about 2900-3000 with a ptc 9.5" to really crank with re journal 6265. It stalled to 5400@28-29psi.
818GN said:
The factory MAF flows terribly even with one screen out. It slows spool on all applications but it is worse the more mass flow the engine uses. Once you get over 500hp with it then remove it you will feel a big increase in spoolup and get a reduction in back pressure since you have raised the air pressure at the inlet of the compressor. It takes less ex energy to build mass flow if you start with close to standard pressure on the inlet. The stock MAF creates a huge vacuum at the inlet when you start making power. On the old 60-1 combo from 2 years ago it was limited by the factory MAF to about 25psi at sea level. Removing the MAF with the xfi install without adjusting the wastegate setting netted almost 35psi and it spooled nearly twice as fast.
Any tests of different MAFs? I know the stock ones were a choke, especially at your flow numbers but what about a true 3" LT1 or bigger LS style? Just curious.
818GN said:
Me and 818GN will be posting some feed back on this turbo after Wednesday. Our set ups are kinda similar and we'll be adding the 6266 to the combos. We ordered 6266 dbb .63 3 bolt exhaust housings with ported S covers. Both using 3200 stall converters.
6266's should arrive Wed/Thur, I am hoping.
Once, they are on, are we go out to a vacant area for tuning, I will post the RPM's at those points mentioned.
Tranny/Converter built and spec'd by 4C's out here in SoCal.
They specialize in Turbo Buick, Typhoon, and Syclone transmissions.
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What psi does the 6266 shine at? 25lbs? 28lbs?
My motor is forged/girdled w/ Champion irons, so I'm not too worried about turning it up.
818GN said:
It flows up to 78lvs/min with the right stuff. With iron heads and off the shelf cam it will take over 30psi to reach that flow. My stock stroke with a 6265 and gn1 ported heads hit that number at 28-29psi. I'd expect it to hit that with your parts around 32-33psi. That's if there is nothing else holding it back like the MAF restriction, intercooler, or converter.
78lvs/min equates to how much rwhp, roughly?
What cam, on a stock stroke, works well with a 6266, and why?
MAF is stock...strongly considering a Translator with proper 3.5inch MAF, ever since you mentioned the flow issues with stock MAF.
Intercooler is a RJC FMIC, so I should not have an issue there.
I did a dyno test with the 6265 about 8 months ago. I posted results in a thread. It was done at less than 3:1 PR on my stock stroke but the heads were really good. I was actually slightly over cammed for that turbo to make peak cylinder pressure when run all out. I'd likely use a 210-214* fast ramp lobe with 110-112*LS and advance it 2-4* depending on a few things. I had a custom 218 in it and it still worked like a champ but peaked a little later than I'd want trying to milk the most out of the turbo. Peaking at 5400 on a stock stroke with the compressor around 2.8:1 PR, 76-78lbs/min would be ideal. I made 696whp with mine@28-29psi then it was done. I went up over 30 and it blew hot air to the point my charge air at the plenum was up 60-70* over the best performance I got and that's with dual alky. So alot of heat. Another area that could show some gain with that compressor is the cover. The S cover is as big as they offer and it could likely pick up a little especially the way I ran it with more compressor cover. Even if it picked up 4-5lbs/min it would have let me get to about 725whp.
It would depend on what your looking for. With a smaller cam and less heads than I used it will take a lot more boost to get the mass flow. To hit up near 78lbs/min you're looking at at least 32-33psi with a really efficient converter that could hold the engine around 5000 rpm as long as possible. I'd run a tall slick and you will need a lot of octane to get it done.
