12.34 with homemade twins

SDP

SDP

AKA Dmax15
Dec 20, 2008
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Port Angeles, WA
Ran a 12.34 at 108mph last night, I'm pretty dissapointed. Had a huge boost leak I'm guessing only seeing 37-38psi when normal was 55-60psi. Must have developed it in the last day or two so it was pretty bad timing. 60ft was 1.80, there wasn't any track prep since it was just time trials and I only took two runs since it wasn't running well.
 
TrentNell

TrentNell

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Jul 7, 2008
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I wouldnt be disapointed with that , the Et was very good for that MPH . I would guess the boost leak is the cause for the low MPH .

It takes time to get top #'s out of a setup it doesnt happen over night , heck it took me 25-30 passes to drop from 12.0-11.6 just getting a .1 better each time out tweeking tunning , 60ft , ect get that boost leak fixed and see what happens . a 12.3 isnt anything to be ashammed of good sixty and no leak it might go 11's ..................
 
SDP

SDP

AKA Dmax15
Dec 20, 2008
261
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Port Angeles, WA
TrentNell said:
I wouldnt be disapointed with that , the Et was very good for that MPH . I would guess the boost leak is the cause for the low MPH .

It takes time to get top #'s out of a setup it doesnt happen over night , heck it took me 25-30 passes to drop from 12.0-11.6 just getting a .1 better each time out tweeking tunning , 60ft , ect get that boost leak fixed and see what happens . a 12.3 isnt anything to be ashammed of good sixty and no leak it might go 11's ..................
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Yeah the boost gradually dropped off from 45psi and a ways before the 1/8th it was down to 37psi or so, that could explain MPH, it was 108.7.

I realize they were decent times for the first time out but I'm disappointed that it was running so well before and it developed the problem heading to the track. I don't like the feeling of knowing it should have done better after all the hard work, I guess on the bright side I have all winter to get it set up how I want it. Not too bad for having less than $16K into everything.
 
TrentNell

TrentNell

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Dmax15 said:
Yeah the boost gradually dropped off from 45psi and a ways before the 1/8th it was down to 37psi or so, that could explain MPH, it was 108.7.

I realize they were decent times for the first time out but I'm disappointed that it was running so well before and it developed the problem heading to the track. I don't like the feeling of knowing it should have done better after all the hard work, I guess on the bright side I have all winter to get it set up how I want it. Not too bad for having less than $16K into everything.
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It happens to every one at some point , I spend an hour before every time i go to the track and look over every inch of the truck , check all boost connections , look for exhaust leaks ,check steering and chassis , ect . Since i started doing this i have not had a spoiled trip out since .
 
SDP

SDP

AKA Dmax15
Dec 20, 2008
261
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16
Port Angeles, WA
TrentNell said:
It happens to every one at some point , I spend an hour before every time i go to the track and look over every inch of the truck , check all boost connections , look for exhaust leaks ,check steering and chassis , ect . Since i started doing this i have not had a spoiled trip out since .
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That's a good idea. I also added pulse width to the tune and was going to try it if things were going well, I've been holding rail pressure so I'm sure it would have helped me get closer to 11's.

Upgrading both turbo's during the winter and hopefully a few other changes to help get me there, my goal is mid 11s for next summer but I'm sure it'll take a lot to get me there
 
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TheBac

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Congrats on the times you ran. MPH is about right for the ET. You'll get it next time!
 
SDP

SDP

AKA Dmax15
Dec 20, 2008
261
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Port Angeles, WA
TheBac said:
Congrats on the times you ran. MPH is about right for the ET. You'll get it next time!
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Thanks Tom!

And yeah its the stock intercooler, LB7's don't have issues that I know of with them. Mine has aluminum end caps so I'd think it should be just fine.

Found the problem, just went and looked it over. I had overlooked the wastegate line on the stock turbo, it blew off in a spot where it hadn't been before:eek:. I thought it was held on there good enough but I guess not, when you double boost pressure I guess it can cause the unexpected to happen. Something so simple that took me a couple seconds, wish I would have found it last night and I could have made a few more runs and messed with the tune.
 
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TheBac

TheBac

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Dmax15 said:
Thanks Tom!

And yeah its the stock intercooler, LB7's don't have issues that I know of with them. Mine has aluminum end caps so I'd think it should be just fine.

Found the problem, just went and looked it over. I had overlooked the wastegate line on the stock turbo, it blew off in a spot where it hadn't been before:eek:. I thought it was held on there good enough but I guess not, when you double boost pressure I guess it can cause the unexpected to happen. Something so simple that took me a couple seconds, wish I would have found it last night and I could have made a few more runs and messed with the tune.
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You're welcome. Look at it this way: thank your lucky stars it was something simple. Funny how we always tell ourselves to look for that kind of thing first, but we miss it anyway. (This coming from the guy who thought he hurt his motor but it was just a loose bale connector!) Bet you'll run an 11 next time!
 
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TheBac

TheBac

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Apr 19, 2008
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How do you like the uppipes?

I just noticed you're basically a stock engine twinned with an S475. Very nice! :thumb:
 
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SDP

SDP

AKA Dmax15
Dec 20, 2008
261
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16
Port Angeles, WA
TheBac said:
How do you like the uppipes?

I just noticed you're basically a stock engine twinned with an S475. Very nice! :thumb:
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Yeah but you still have me beat with just the stock turbo:thumb:

Up pipes did make a difference, worked as advertised and worth the money. I'm thinking about going to the cast manifolds and up pipe combo this winter for more of a gain.

Its crazy how much faster it is on the top end now without the leak and the wastegate on the IHI opening now.

Was on my way down to Portland again tonight but it ended up raining so I turned back after 3-4hrs of driving, also got in a fender bender:mad:. Teaches me to run bald tires in the rain I guess, it was stop and go traffic for a half hour straight and it just took one instance of not paying attention.
 
Osubeaver

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Aug 30, 2008
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Dmax15 said:
Was on my way down to Portland again tonight but it ended up raining so I turned back after 3-4hrs of driving, also got in a fender bender:mad:. Teaches me to run bald tires in the rain I guess, it was stop and go traffic for a half hour straight and it just took one instance of not paying attention.
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Sorry about the fender bender, that sucks!

You should have kept driving. It didn't rain and there was hardly anybody at the track. You could hot lap if you wanted.

Oh well, see you next season :thumb:
 
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