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Discussion Starter #1 (Edited)
Some help with my 67DBB on the dyno and results.

Well my friends and I recently added hks 264 cams on the car so we went ahead and took it to the dyno. The good news on 30-31 psi it hit 702rwhp and 590 torque. The bad news, I'm getting a slight hesistation right when its about to come on hard. Its feels like its about to pick up mass power, pauses for a split second, then bam, it kicks in full force. Really wierd, and I cant understand why. Anybody have any ideas or suggestions??? You can see on the dyno sheet where it does that.
Link to dyno sheet http://img.photobucket.com/albums/v479/denmah/cars/costasdyno/costasdyno.jpg

And if anybody is interested, link to the video. http://www.youtube.com/watch?v=pRtdV_XJk0o

My mods. BL 67DBB, BL fuel system, HKS 264 cams, BL exhaust, VPC, SAFC2, greedy boost controller.
 

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Working OT
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That's wierd and it's odd that it bounces then shoots up. What you using for tuning?
 

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Working OT
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Really wow that's impressive. I keep planning on going aem but I'm seing alot of guys put down good numbers with out it.
 

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I had a similar problem when I was running the VPC & SAFC combo... I had to add some fuel at 4k rpms right before full boost (In your case it looks like you need to take out some) and smooth out my fuel -/+'s for example: ( the VPC should all be a 12'oclock) On the SAFC Fuel map.. you can't have 0, 0, 0, -3,-3,-3 etc.. you have to gradually add or subtract like 0, 0, +1, 0, -2, -3, -3 etc...

Hope this helps!
 

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I had a similar issue with Stock twins, AFC, and an OBDI ECU.

It was too much fuel at transition, where the ECU switches fuel maps. I bet you added fuel at this point as well, and the ECU is fighting it.

The only way I found around it (without changing equipment) is just let it be leaner at that spot.

Hope this helps.
 

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can't tell by your dyno graph of your air fuel. Can you get a more detail of it? it looks pretty straight to me and looks to be below 12?
 

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Boost Junkie
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Yeup, need to lean out the a/f between 4-5k rpms.

Steve
 
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