Behold And Be Amazed At This $ To Hp Ratio

69Rcode_Mach1 said:
I know the kind of letdown you are feeling. Also what is the elevation where you live, that and the C6 together could lead to a huge decrease in power.

Thanks. What nobody seems to realize is that I am not complaining that these mods failed to net me significant gains. Rather, I am bummed that my build is getting me 385 hp or less at the fly. I was really hoping to get at least 400. My torque numbers are there and I am happy with them (400 ft lbs at the rear wheels) I just don't understand why the hp isn't there as well. As for my elevation, I am at 9 feet below sea level. Sometimes a bit more.
 
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here is my dyno

3455453923232%7Ffp63%3Dot%3E2354%3D%3A79%3D639%3DXROQDF%3E232424495736%3Bot1lsi
 
Max Power said:
Sounds like you are more concerned about a number than actual performance.

Maybe I am where I should be. If the conventional wisdom about an old C6 eating 25% of your hp is correct, then I have 400 hp at the fly and I can be satisfied with that. When I discussed my build with the shop back in the States, I was talked out of stroking it because with a hot build, I would see 400 hp, which is more than plenty for a street car. when I wasn't seeing that, I was thinking that something was wrong with my build. I am not concerned about the number per se. Regarding dyno bench racing, been there, done that, got the t-shirt. What was causing distress was seeing guys with similar builds getting better numbers. Better numbers mean better performance and at the end of the day, I want every last pony out of my pony, if you know what I mean. If it is in there, I want it out here.
 
Jerry if you are at sea level or even below it something is not right you should be seeing a lot more power than that. Those are the kinds of numbers a 5.0 would lay down with a similar combo, something is not right. The C6 is eating up sooooo much of your power, I know this from experience, so that is a huge factor. It could eat up atleast 80 or more hp to your wheels from the flywheel. You may want to look into a built C4 down the road.
 
The C6 has one of the largest parasitic drags of all trannys. I think in order from the least to the most, as far as Ford/GM it's: Powerglide, T350, C4, T400, C6. I don't know where the 727 falls in there, I think it's before or after the T400.

PA (Performance Automatic) builds a really nice tranny as far as a high performance application. They tend to build mainly Ford trannys, but do Powerglides as well. They also do AOD/AODE and E4OD as well as the C4/C6. Their Super Streeter C4 handles up to 450hp runs about $1075, and their SS AOD runs $1950. They even have a spline adapter for $64 to adapt a C6 converter to a C4 tranny if you like your converter.

My buddy bought a C4 Super Comp tranny with a brake at WFC a couple years ago for a little over $1600 and they had it there at the track. It lists on their site for $2450 now and I think then it was $2000. Cool thing about it is that it has a lifetime warrenty. It breaks, you send it in to be fixed for free, you only pay shipping to their place. They reccommend you send it in after every season and they freshen it up, again, free, just pay shipping. I think they even send you a case to ship it in. Now this isn't as great for you, where your at, but if you come back to the states....

http://www.performanceautomatic.com
 
mustangdave said:
I would check timing first: make sure you have around 34-36 dgrees of total timing all in by 3500 r.p.m. Once that is adjusted, work on carb. adjustments.

Ok. I asked and was told that the total advance was 28 degrees. That seems less than it should be. Also, they disconnected the vacuum advance. They said that with the high compression on my car (11:1) that keeping it connected would mess with the idle. Does this sound right?
 
Edbert said:
I couldn't agree more with this statement, but with those heads/intake and that cam he SHOULD be over 400 at the flywheel. Do you not agree?

Sure...but I didnt know what heads he had at first. There's definitely something odd going on, and the dyno 'tuning' so far aint getting it.

Ah, and you are in the UK. I'm perty slow on the uptake, it seems :p
Your combo 'smells' like ~450 fwhp to me. FWIW.
 
You may benefit from more timing...the tuners should have experimented on teh dyno. Also...there is no need to run vacum advance. Just the mech advance in teh dizzy. Make sure all the advance is in by 3k rpm.

Do you have big/heavy wheels and tires?

What was the weather of the day you dyno'd compared to last time?

You may want to look into getting the cam degree'd.

Maybe you intake gaskets aren't lined up perfectly partially blocking a port.....there are just too many variables until you start eliminating possibilities.
 
LMan said:
Sure...but I didnt know what heads he had at first. There's definitely something odd going on, and the dyno 'tuning' so far aint getting it.

Ah, and you are in the UK. I'm perty slow on the uptake, it seems :p
Your combo 'smells' like ~450 fwhp to me. FWIW.

actually in the NL but close enough. And you are right as to how my combo smells or should smell, hence my dissatisfaction with where it is at the moment.
 
jerry S said:
Ok. I asked and was told that the total advance was 28 degrees. That seems less than it should be. Also, they disconnected the vacuum advance. They said that with the high compression on my car (11:1) that keeping it connected would mess with the idle. Does this sound right?

Your dyno sheet is hard to read but it would appear to be missing 1 critical thing during the run. That is the Air/Fuel ratio. I wouldn't be surprised if you were super rich especially with 28 degrees. Most SBF's like a total timing of 36.
 
Two more points (never heard back about the EU fuel formula either):

The C6 will suck up a lot of power compared to a C4, but so will the 9 compared to an 8. I know a local guy who changed his 8 out for a 9 and lost 0.75 in the 1320!

Different dynos will produce different numbers. I have read that the same car on the same day can get 10-15% differences depending on which one they use. Around here they have DynoJets and Mustang ones (no relation). I cannot remember which one routinely gives higher numbers though. I have not heard of the one you used but it is conceivable that it gives out lower numbers than the other kinds.
 
Edbert said:
Two more points (never heard back about the EU fuel formula either):

sorry Edbert. I was not ignoring you just hunting down the info. We use the RON measure while you use the PON measurement. We get 98 octane RON here which is 94 PON (what you get).

The C6 will suck up a lot of power compared to a C4, but so will the 9 compared to an 8. I know a local guy who changed his 8 out for a 9 and lost 0.75 in the 1320!

maybe it is time to think about a C4 and an 8.8

Different dynos will produce different numbers. I have read that the same car on the same day can get 10-15% differences depending on which one they use. Around here they have DynoJets and Mustang ones (no relation). I cannot remember which one routinely gives higher numbers though. I have not heard of the one you used but it is conceivable that it gives out lower numbers than the other kinds.

this is a dynojet.
 
rhyno9 said:
Your dyno sheet is hard to read but it would appear to be missing 1 critical thing during the run. That is the Air/Fuel ratio. I wouldn't be surprised if you were super rich especially with 28 degrees. Most SBF's like a total timing of 36.

The tuner said the A/F was between 5-6.
 
Air fuel ratio should be around 12:1 give or take a little. You definitely need more total timing. The difference in 28 and 36 degrees can account for alot of power. Dial in as much as you can without detonation.