Has anybody done a roots blown LSx?
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Im currently building a 403ci 8-71 Roots blown setup. If you have a similar setup I would like to see some pics (of the drive/cog/accessory setup). Or If you have any usful tips/info that would be great. This is a path that I am finding not many people have taken and need some support! lol.
It is going into a 3rd gen Camaro with the engine set back 8", new fabed fabed firewall so space really isnt an issue. headers are also customed fabed and routed through the firewall to under the car where the sideskirts usually are.
Any pics/info would be helpfull! Thanks!
It is going into a 3rd gen Camaro with the engine set back 8", new fabed fabed firewall so space really isnt an issue. headers are also customed fabed and routed through the firewall to under the car where the sideskirts usually are.
Any pics/info would be helpfull! Thanks!
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Yea, there was a guy that just did one not too long ago. Search through the forced inductions threads and you should find it. I saw it less than a month ago. It's a great looking engine.
Im currently building a 403ci 8-71 Roots blown setup. If you have a similar setup I would like to see some pics (of the drive/cog/accessory setup). Or If you have any usful tips/info that would be great. This is a path that I am finding not many people have taken and need some support! lol.
It is going into a 3rd gen Camaro with the engine set back 8", new fabed fabed firewall so space really isnt an issue. headers are also customed fabed and routed through the firewall to under the car where the sideskirts usually are.
Any pics/info would be helpfull! Thanks!
It is going into a 3rd gen Camaro with the engine set back 8", new fabed fabed firewall so space really isnt an issue. headers are also customed fabed and routed through the firewall to under the car where the sideskirts usually are.
Any pics/info would be helpfull! Thanks!
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Your in luck. I'm the one and only guy that has done this within the last 10 years. haha. What do you need to know? I just did a 408ls 10-71 roots with BDS efi bug catcher. I ran the full holley dominator EFI.
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We did a lot of R&D for BDS even though they say they have done this. There belt sizes were wrong, boost levels wrong etc. When setting up the pullies base the boost level off of a 500ci bbc and you'll be close. What they sent for a 12lbs of boost was actually 7lbs of boost. I also sent BDS about 12 datalogs from my pulls. So they should have some good info to base the ls setup off of if your going with them? 9lbs of boost and my hottest AIT was 98*.
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That is awesome! Sounds like you are the right person to be talking to! Ive got some questions...For one, im debating on running a single dominator or a manual FI system (already have most of the components for both sitting around from years past). The other main thing is the lower belt drive. Im concerned with crank failure because the lower cog is so far away from the crank. Also are you running any type of damper? What setup are you using on the lower drive? Any fitment issues for the drive system? Did you use the bds drive kit?
Also some other tidbits: Im going to fabricate my own intake manifold (no offense but i just dont like the choices that are out there). Thoughts? Is this going to be a street driven engine? Mine is... I didnt want to punch out the block any more than I have to to preserve cyl wall thickness. I originally considered 408ci but settled on 403 ish, 4.001 bore/4.000 stk. Thoughts. Thanks for all the info and help, it hard to find on this stuff!
Also some other tidbits: Im going to fabricate my own intake manifold (no offense but i just dont like the choices that are out there). Thoughts? Is this going to be a street driven engine? Mine is... I didnt want to punch out the block any more than I have to to preserve cyl wall thickness. I originally considered 408ci but settled on 403 ish, 4.001 bore/4.000 stk. Thoughts. Thanks for all the info and help, it hard to find on this stuff!
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Ya I was thinkin the same thing seeing your snout and cr4ank pullies wayyy the hell out there. Was thinking there might be a wat to make a brace that goes between the SC pulley and crank pulley that makes it so they arent tearing themselves towards the center.
GL!
GL!
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I'm tuning the BDS belt drive. I needed to swap spacers from top to bottom and take spacers out not a bolt in drive kit like the say. I'm also not running a damper. The drive belt takes care of that. As far as crank failure that won't be an issue as the aux belt pulley (damper) goes on the crank, then the spacers and cog pulley bolt to that. So the grade 8 bolts are taking all the stress on this setup. I agree on the intake 100% if you can build one do it. The BDS intake is a nice piece but I could have spent hours port matching everything. I didn't because everything started large and got smaller as it went to the heads. This is a street strip engine. I ran out of dyno time so I'm going to put it back on this winter again this time with 15 lbs of boost and E98. The 9 lb setup is hardly turning the blower at all. My opinion do the mechanical fuel injection. I don't think the single dominator will do it. At 9lbs of boost it was pulling fuel as if it was a 505ci engine. I'll look at my dyno sheets to see the exact fuel consumption. The stock block at .030" over is good for about 1,200 hp so they say. What blower are you going with? The BDS high helix is one kick *** blower. The more boost you through at it makes it look like a whipple screw. I was surprise at the efficiency of this blower compared to all the other roots.
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I built my 427 c.i., LSX block, 8-71 BDS blower, E.F.I. engine two years ago. Mapped to run on pump gas, 110 race gas and E85. E85 really stepped up the horspower. The engine build was featured in the May 2009 issue of Hot Rod magazine.
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Im going with the 8-71 AL from bds with their 8-71 ls drive kit. I guessed it would take some tweaking because they just came out with the kit...Im still undecided on running e85 or pump through this motor. I really want the benefits of the e85 but the availability where I live is poor to say the least. Its mostly a street car and will make around 10 passes a year...btw i like the engine dyno. Looks really similar to the start-stand i used to have until i took it apart for parts lol.
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I finally checked and at 9lbs of boost at 6,500 rpm my engine was at 632.9lb/hr fuel rate if that helps you decide what induction to use. That pull made 824.6hp @6,500 714.4tq @ 5,300.
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Thats great info, it really helps! Thanks for all the input! Im going to take an inventory of the parts I have. I think I am just short a pump for the MFI..