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Posted

Still toying with the idea of building the carb for running e85? I think that would be outstanding from a performance stand point.

Posted

f476d24af164913e19490ca31490ac9a.jpg

Not trying to be a butthead my vote is around 700HP hard to imagine more without a blower or NOS. Good luck!
Posted

OK, quick research shows a high RPM lockup convertor on a TH400 can kill dyno readings. A 11 second Camaro dyno'ed 350RWHP according to one website. That could be the issue

Posted

Nope. LS1 tech a guy talks about a 11 second Camaro with a 468CI V8 that couldn't break 360HP on a dyno because he had a really high stall in his TH400.

 

My best bet is:

Slicks and a 1/4 miles and trap speed, then get weight and do the HP calculation.

Posted (edited)

1967 Firebird 541 V8 Dyno Pull:

 

Started recording a bit late.

 

Turns your speakers up, especially if you pull it up on your TV and home theater.

Edited by SnakeEyes
Posted

sounds awesome, you'll have to "hand calculate" the HP and let us know what it is. Were you able to get an accurate torque number or is there a way to manually figure that out also.

Posted (edited)

sounds awesome, you'll have to "hand calculate" the HP and let us know what it is. Were you able to get an accurate torque number or is there a way to manually figure that out also.

Nope, I don't know if the TC locked up well or at all. Lots of talk around the net of people that say they won't, they will just fine, they might. Have some old Camaro guys looking at the power curve sheet, something wasn't going well. My rev limit is set atvmy Digital 6 Plus at 6600, but at 5800 power drops and the lines squiggle.

 

One guy thinks I might have a internally broken spark plug, or dislocated High Tension lead. (Which I believe is just a spark plug wire, and the guy is really old school)

 

 

Seems to me if that was the case I would have a lot more driveability issues.

Edited by SnakeEyes
Posted

Nope, I don't know if the TC locked up well or at all. Lots of talk around the net of people that say they won't, they will just fine, they might. Have some old Camaro guys looking at the power curve sheet, something wasn't going well. My rev limit is set atvmy Digital 6 Plus at 6600, but at 5800 power drops and the lines squiggle.

 

One guy thinks I might have a internally broken spark plug, or dislocated High Tension lead. (Which I believe is just a spark plug wire, and the guy is really old school)

 

 

Seems to me if that was the case I would have a lot more driveability issues.

 

Were you thinking 700-800 wheel hp or crank hp?

Posted (edited)

Were you thinking 700-800 wheel hp or crank hp?

Crank. I'm not a moron, none of these old big Cubic inch motors could make that at the wheels with 91 octane naturally aspirated.

 

 

My best pull was 479 HP 443 TQ.

 

Look what happens at 5500RPM. On some sites now asking if anyone knows where to start. All I have so fas is "plugs and wires". I didn't think plugs and wires would cause problems at the same RPM EVERY pull, but be stable under that RPM.

 

Reading even more talk about stalls in TH400s. Seems like a lot of people get low numbers. One guy said the same engine with no changes except trans:

T56, and a TH400 with a high rpm stall. TH400 dyno'ed something like 150 LESS torque....but the guy gained a full second ET I'm 1/4.

 

A lot of people seem to say a chassis dyno is useless on these trans with high stalls.

 

hn93qwI.jpg

Edited by SnakeEyes
  • Like 1
Posted

Crank. I'm not a moron, none of these old big Cubic inch motors could make that at the wheels with 91 octane naturally aspirated.

 

 

My best pull was 479 HP 443 TQ.

 

Look what happens at 5500RPM. On some sites now asking if anyone knows where to start. All I have so fas is "plugs and wires". I didn't think plugs and wires would cause problems at the same RPM EVERY pull, but be stable under that RPM.

 

Reading even more talk about stalls in TH400s. Seems like a lot of people get low numbers. One guy said the same engine with no changes except trans:

T56, and a TH400 with a high rpm stall. TH400 dyno'ed something like 150 LESS torque....but the guy gained a full second ET I'm 1/4.

 

A lot of people seem to say a chassis dyno is useless on these trans with high stalls.

 

hn93qwI.jpg

I certainly didn't mean to imply that you were a moron. It's just that this is the internet and you never know who's on the other side of the screen.

 

I don't know your engine specs. I assume this is a solid and not hydraulic valve train?

 

Under that assumption, my first thought would be some where in the ignition system too. I have certainly seen plugs do this. I have also seen a wonky distributor do it.

 

How old is that digital 6 plus box? I just had to replace mine because it under load around the same rpm would make the car feel like I was hitting the rev limiter. I even tried adjusting the rev limiter to 9500 and it would still do it right around 5500 rpm. Long before my shift light.

Posted

Also, what other forums have you been on?

 

I recommend speedtalk.net

 

Some of the premier engine builders in the country frequent there.

Posted (edited)

Also, what other forums have you been on?

 

I recommend speedtalk.net

 

Some of the premier engine builders in the country frequent there.

TeamCamaro.net

 

 

And just started hotrodders.com they have several regular Poncho guys, whose posts have turned up in google search when I'm looking into something.

 

TC is a 1st gen specialty site, but not REAL big on performance set ups like mine. (There was nearly a meltdown when they saw my Pontiac fuel pressures at 80 PSI at throttle when cold, thought it was done for, but its a normal Pontiac V8 thing)

 

A guy on hotrodders gave me new settings for my digital 6 plus box, which was set to 9.9 timing retard(max). We both figure that was leftover from the blower days. I hadn't paid much attention to the setting since the car was running well. I'll be upset with myself if its a lot better tomorrow.

Edited by SnakeEyes

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