Turbo BB?

[Sweet5ltr]

Looking at running dual inline walbro 255gph (GL392 part # external) fuel pumps. This would nail my fuel system and keep it under $180 bucks in comparison to a $400 A1000 aeromotive. If I win that carb setup, I will be $900 into literally my entire fuel system which was going to 'nickel and dime me' the most.

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A few ideas. First the boost referenced regulator simply has a port on the atmosphere side of the diaphragm. easy on just about any regulator. Normally a small block with iron heads likes around 35. We found at mild boost, 10-12, we only needed to run 20 total. On the initial dyno hits when we couldn't get it rich enough .Also the converter was so loose it stalled to 5300. Even then the 360 made 475@5600 to the wheels at 9 psi.
Doug

Thanks a ton Doug for your input on my thread,
What I have been reading from the BBC and BBF guys (turboforums) is that E85 can run a substantial amount of additional timing. Another topic they touched base on was with big single turbo setups, timing wouldn't need to be pulled until 5psi, in which then, it was 1*/per psi. The car runs 34* now, I believe we could get away with this or go down to 32* total (distributor is locked) and be fine. Let me know how you feel about this. I don't want to be in a few hundred bucks to pull a few degrees of timing. 6-8psi is goal, nothing more. To me, most everyone runs 36-38* timing anyways, normally,pulling even up to 2* retard per psi post-5psi would get me to my current timing level.

On the Boost Referenced Regulator;
I have the understanding that the boost pressure regulator adds 1psi of fuel pressure per 1psi of additional boost (1:1). I would be looking at around 16-20psi total possibly. Please help me out if I am wrong. Thanks.

 

[Herr_Poopschitz]

A few ideas. First the boost referenced regulator simply has a port on the atmosphere side of the diaphragm. easy on just about any regulator. Normally a small block with iron heads likes around 35. We found at mild boost, 10-12, we only needed to run 20 total. On the initial dyno hits when we couldn't get it rich enough .Also the converter was so loose it stalled to 5300. Even then the 360 made 475@5600 to the wheels at 9 psi.
Doug

What compression ratio are you guys running, and did you try it w/ more timing? Seems like you'd be leaving a ton of power on the table by only running 20 total, esp w/ e85...I ran that on 91 w/ similar boost...

I still don't like the idea of only running 6 psi...that turbo won't like it either w/ no intercooler or something to drive the compressor outlet pressure up...

Pg 41
http://www.turbodriven.com/files/pdf/BWTS_2011_Catalog_SMALL.pdf

 

[Sweet5ltr]

What compression ratio are you guys running, and did you try it w/ more timing? Seems like you'd be leaving a ton of power on the table by only running 20 total, esp w/ e85...I ran that on 91 w/ similar boost...

I still don't like the idea of only running 6 psi...that turbo won't like it either w/ no intercooler or something to drive the compressor outlet pressure up...

Pg 41
http://www.turbodriven.com/files/pdf/BWTS_2011_Catalog_SMALL.pdf

looking at around 8psi as a goal. Not really trying to have any 'crank walk' or cracked blocks in my future. Car has SFI damper and all the goodies, and bottom end was balanced/blueprinted. Just looking for conservative power numbers.

 

[Herr_Poopschitz]

Oh...when you say 'locked', what exactly do you mean? Used to be 'locked' meant no timing adjustment whatsoever...like 'locking' it at 18 deg, never goes lower, never goes higher. Unless you mean something different, I think you'll have a number of probs w/ it at 32...starting it could be difficult, idle, cruise, tip in, etc.

You may look into recurving the distributor based on what rpm the manifold starts seeing positive pressure. On the other hand, I don't see why 32 total would be unacceptable w/ 85 and relatively low manifold pressures.

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looking at around 8psi as a goal.

If you run 8 psi w/ an intercooler that has a ~3psi drop across the core, that will get your pressure ratio up and increase the compressor efficiency to a point where you can even locate it on the map...haha.

 

[dvw]

What compression ratio are you guys running, and did you try it w/ more timing? Seems like you'd be leaving a ton of power on the table by only running 20 total, esp w/ e85...I ran that on 91 w/ similar boost...

I still don't like the idea of only running 6 psi...that turbo won't like it either w/ no intercooler or something to drive the compressor outlet pressure up...

Pg 41
http://www.turbodriven.com/files/pdf/BWTS_2011_Catalog_SMALL.pdf

Compression ratio is 9-1. We tried more timing with no improvement. We thought the same thing it would make more power, but it didn't go any quicker at 24. We stopped there. On the 10.08@136 pass it had 17 total. Do the math. 3700lbs@136= 750+ HP
Doug

 

[Sweet5ltr]

Oh...when you say 'locked', what exactly do you mean? Used to be 'locked' meant no timing adjustment whatsoever...like 'locking' it at 18 deg, never goes lower, never goes higher. Unless you mean something different, I think you'll have a number of probs w/ it at 32...starting it could be difficult, idle, cruise, tip in, etc.

You may look into recurving the distributor based on what rpm the manifold starts seeing positive pressure. On the other hand, I don't see why 32 total would be unacceptable w/ 85 and relatively low manifold pressures.

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If you run 8 psi w/ an intercooler that has a ~3psi drop across the core, that will get your pressure ratio up and increase the compressor efficiency to a point where you can even locate it on the map...haha.

No intercooler, haha. Locked meaning yes, locked total timing currently. No mechanical advance or timing curve. Car runs great, idles cold. Great response off the line, and no complaints. I am just asking, could I run my current locked dizzy at 32-34* with the turbo on E85 and not worry about a boost retard box? I'm trying to accomplish this on a limited budget obviously. Going to talk to a close friend with a turbo outlaw car this week on this subject.

Any complaints on my fuel system choice?

 

[Herr_Poopschitz]

Compression ratio is 9-1. We tried more timing with no improvement. We thought the same thing it would make more power, but it didn't go any quicker at 24. We stopped there. On the 10.08@136 pass it had 17 total. Do the math. 3700lbs@136= 750+ HP
Doug

Yep, that's weird. What was A/F?
What kinda heads you runnin'?

Car is boogeyin'. My Dad thinks I'm crazy, but I love '62s.

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No intercooler, haha. Locked meaning yes, locked total timing currently. No mechanical advance or timing curve. Car runs great, idles cold. Great response off the line, and no complaints. I am just asking, could I run my current locked dizzy at 32-34* with the turbo on E85 and not worry about a boost retard box? I'm trying to accomplish this on a limited budget obviously. Going to talk to a close friend with a turbo outlaw car this week on this subject.

Any complaints on my fuel system choice?

I don't think you'll have a prob at 32 deg.

I like the walbro pumps. F Aeromotive and their overpriced mediocre stuff.

If you can't afford a retard box, how are you going to afford to fix the engine when you blow it up? (J/k, kinda)

You will hate the 4.10s and want to change them immediately.

Again, not sure about that turbo for what you're wanting to do. You NEED to learn to read a compressor map...don't just throw parts at it cuz someone told you it would work.

 

[Sweet5ltr]

Yep, that's weird. What was A/F?
What kinda heads you runnin'?

Car is boogeyin'. My Dad thinks I'm crazy, but I love '62s.

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I don't think you'll have a prob at 32 deg.

I like the walbro pumps. F Aeromotive and their overpriced mediocre stuff.

If you can't afford a retard box, how are you going to afford to fix the engine when you blow it up? (J/k, kinda)

You will hate the 4.10s and want to change them immediately.

Again, not sure about that turbo for what you're wanting to do. You NEED to learn to read a compressor map...don't just throw parts at it cuz someone told you it would work.

I am actually reading the compressor maps now, turbo may need to push some more pressure to be efficient in the least bit. I am just asking is it necessary, nothing more, I can afford it but if it isn't necessary then I am not going to place it on the car.

 

[Herr_Poopschitz]

I am actually reading the compressor maps now, turbo may need to push some more pressure to be efficient in the least bit. I am just asking is it necessary, nothing more, I can afford it but if it isn't necessary then I am not going to place it on the car.

You could look for a diff turbo that will more closely match what you intend to do...

 

[dvw]

Yep, that's weird. What was A/F?
What kinda heads you runnin'?

Car is boogeyin'. My Dad thinks I'm crazy, but I love '62s.

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I don't think you'll have a prob at 32 deg.

I like the walbro pumps. F Aeromotive and their overpriced mediocre stuff.

If you can't afford a retard box, how are you going to afford to fix the engine when you blow it up? (J/k, kinda)

You will hate the 4.10s and want to change them immediately.

Again, not sure about that turbo for what you're wanting to do. You NEED to learn to read a compressor map...don't just throw parts at it cuz someone told you it would work.

The heads are 308 castings with some bowl work. We read the fuel air off the gas scale for convenience. We've been from 10.8 up to the mid 11s.
Doug

 

[Sweet5ltr]

You could look for a diff turbo that will more closely match what you intend to do...

What turbo do you recommend in the same budget bracket? It may be ill efficient, but if it builds 600rwhp at 10psi does it matter? People run this thing on 5.3-5.7 LSX builds, I can't see it being even a remote match but it seems to work.. To the best of my reading abilities via the compressor maps, 10psi seems to be the ticket on the low end to even get remotely efficient, so i'll shoot for 10-12psi.

 

[Herr_Poopschitz]

What turbo do you recommend in the same budget bracket? It may be ill efficient, but if it builds 600rwhp at 10psi does it matter? People run this thing on 5.3-5.7 LSX builds, I can't see it being even a remote match but it seems to work.. To the best of my reading abilities via the compressor maps, 10psi seems to be the ticket on the low end to even get remotely efficient, so i'll shoot for 10-12psi.

Booyah. Stop being a pussy and let 'er eat!

Nice thing about the turdbo too is you won't have to wind the piss out of it, so the likelihood of breaking stuff at the same power levels as n/a guys goes down dramatically.

Sounds like you have a plan. Start saving for a clutch...and go buy some Depends.

 

[Sweet5ltr]

Booyah. Stop being a pussy and let 'er eat!

Nice thing about the turdbo too is you won't have to wind the piss out of it, so the likelihood of breaking stuff at the same power levels as n/a guys goes down dramatically.

Sounds like you have a plan. Start saving for a clutch...and go buy some Depends.

Have a Centerforce DFX already.. Centerforce said it's good for 650-700 ponies.. Strongest single disc 11" clutch I believe. Well, if all this works out, we'll see.

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Have a Centerforce DFX already.. Centerforce said it's good for 650-700 ponies.. Strongest single disc 11" clutch I believe. Well, if all this works out, we'll see.

Plan on possibly trading my 4.10's. Gearing is comparable to a 3.73 with a 26-27" tire. Optimal for me would be 3.23's. I don't think I would have any issue trading a 742 w/ 4.10s and a richmond locker for a 3.23 sure grip. Would make around a 3.00 gear set with my 30" ET Streets.

 

[Supershafts]

When taking CAM advice REMEMBER you don't have a 360" sb, and whether you're using a turbo or not, THEY are not the same.

You are still putting air into the same 500" motor that has changed the way it wants it.

The guys doing that 800 and 1000hp streetable turbo cars aren't running little cams, and you can simply change the performance level you want by changing the boost and lowering it.

Cracking the block is far easier with gm and ford, i also would not lose performance by leaving it locked at 20 degrees.

You'll find out that you'll wreck rings and gaskets before you wreck the block with the turbo, and you'll find out when you do hurt something that boost isn't the same as N/A motors and can still make big power whereas N/A would be down considerably and more noticeable .
.

 

[Sweet5ltr]

When taking CAM advice REMEMBER you don't have a 360" sb, and whether you're using a turbo or not, THEY are not the same.

You are still putting air into the same 500" motor that has changed the way it wants it.

The guys doing that 800 and 1000hp streetable turbo cars aren't running little cams, and you can simply change the performance level you want by changing the boost and lowering it.

Cracking the block is far easier with gm and ford, i also would not lose performance by leaving it locked at 20 degrees.

You'll find out that you'll wreck rings and gaskets before you wreck the block with the turbo, and you'll find out when you do hurt something that boost isn't the same as N/A motors and can still make big power whereas N/A would be down considerably and more noticeable .
.

What would you recommend for the camshaft department? I know the old wise tale of "112-114LSA" for boost, but have read many stories of racers running radical N/A cams creating heavy overlap with great results with Turbo's. I'm kind of lost between the lines, as I know people who build insane power with factory cams in LSx builds and others who use very radical, turbo specific camshafts and build far less.. Some turbo cam companies state you want an 108LSA and huge amounts of duration, another states low duration and wide LSA. What is your insight on this subject? What is your opinion on timing with a turbo build, is a boost retard box necessary if running low amounts of initial timing on E85. I know the car cranked real easy on 20*, but was over 40* with the factory curve at full advance. We just locked it currently at 34*. I just don't want to rely on a controller, and it end up going out as I have had 3-4 ignition box's go out over the past few years (mallory/msd), and toasting the motor when under boost. I would rather it be a little lousy down low and be great up top. If E85 can give me this ability, then that is another plus. It isn't all about saving a buck! If it is completely necessary, then I have no issue with purchasing one.

 

[Sweet5ltr]

I know, I may need to sacrifice my love for heavy overlap for this turbo build.. I just don't want to order anything with the 'newer' fast ramp rates. I may be able to go with a .557MP solid with a 110LSA. Ideas?

 

[dvw]

When taking CAM advice REMEMBER you don't have a 360" sb, and whether you're using a turbo or not, THEY are not the same.

You are still putting air into the same 500" motor that has changed the way it wants it.

The guys doing that 800 and 1000hp streetable turbo cars aren't running little cams, and you can simply change the performance level you want by changing the boost and lowering it.

Cracking the block is far easier with gm and ford, i also would not lose performance by leaving it locked at 20 degrees.

You'll find out that you'll wreck rings and gaskets before you wreck the block with the turbo, and you'll find out when you do hurt something that boost isn't the same as N/A motors and can still make big power whereas N/A would be down considerably and more noticeable .
.

Granted a 500" turbo street motor will use a larger cam than a 360. However it doesn't take much. Tight lobe centers are not what I would recommend. Look at LS stuff 116-119 sometimes more. I recomended locke timing to save $. The only performance you would lose at locked timing is at cruise. Full throttle is full throttle. In our testing, timing has shown little gain. Not enough to warrant a chance at the motor hurting itself. Again, how fast do you want to go? I'm telling you the simple small block is a hand full. We make 2hp/cu" with nearly stock heads and a [email protected],.490"cam.
Doug
Doug

 

[Sweet5ltr]

Granted a 500" turbo street motor will use a larger cam than a 360. However it doesn't take much. Tight lobe centers are not what I would recommend. Look at LS stuff 116-119 sometimes more. I recomended locke timing to save $. The only performance you would lose at locked timing is at cruise. Full throttle is full throttle. In our testing, timing has shown little gain. Not enough to warrant a chance at the motor hurting itself. Again, how fast do you want to go? I'm telling you the simple small block is a hand full. We make 2hp/cu" with nearly stock heads and a [email protected],.490"cam.
Doug
Doug

Car is mainly a street car, set up for the strip. Would enjoy running in the mid to low 10's, easing it off the line. I already run locked timing, so that is why I am comfortable with doing it again. I am wondering the power gain by running this E85 carb over 93 pump fuel?

 

[dvw]

For what its worth I also have a F-Body with a blown 340. 12lbs of boost@3900lbs . It's been 11.01@122 in street trim. 4.30 gear,loose converter [email protected]"/540" cam. Much less efficient than the turbo. If it had Holleys I'd convert it to E85 in a heartbeat.
Doug

 

[Sweet5ltr]

Any idea of power increase with E85 over conventional fuel? I got some specs on the carb, from what he stated, the carb
was built for a 6ltr procharged chevy. Initial cost was $1,800 from C&S for the carb alone he stated. Still the only bidder on the setup, if I win it, it will save me a great deal on my turbo build.

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For what its worth I also have a F-Body with a blown 340. 12lbs of boost@3900lbs . It's been 11.01@122 in street trim. 4.30 gear,loose converter [email protected]"/540" cam. Much less efficient than the turbo. If it had Holleys I'd convert it to E85 in a heartbeat.
Doug

I think the rear mount is just going to look outrageous hanging under the car with this S475. Any mounting idea's? Will 3" pipe on the exhaust flange and cold side be enough to support 50#? Thinking about just using solid brackets on the exhaust flange tubing near the compressor and the charge pipe where the turbine discharges the air to the carb. I may run the .590 for a bit with the turbo for a baseline, and only 8-10psi. I really just love the sound and it honestly is timid in a big block IMO already.