05 colorado SBE 6.0/C480/4l80e 9.78@143 foot brake 3850lbs
#365
8 Second Club
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The 88/83 doesn't seem to have a problem making 800+ in other cars and the 78/75 appears to be falling off at 700. I guess if 700 is the end goal then the 78/75 fits the bill for sure!
Another question... if the 78/75 is making 11-13hp/lb and takes 20lbs to get to 700, but the 88/83 makes double the hp/lb and can do 700 at lower boost which would you rather have?
#368
TECH Fanatic
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Maybe VS will send him one to do a true back to back
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#370
9 Second Truck Club
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Complete opposite from what I have found..... I've seen a solid 3~4 tenths and same mph at the track from pump gas switching to E85 even with same amount of boost, and timing. Only time I could see this even being close is on a lower boost setup with really cool ambient air, or a really efficient ice water chiller.
#371
9 Second Truck Club
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At the same boost/timing on the same size engine with the same cam? Just curious if its a apples to apples comparison.
The 88/83 doesn't seem to have a problem making 800+ in other cars and the 78/75 appears to be falling off at 700. I guess if 700 is the end goal then the 78/75 fits the bill for sure!
Another question... if the 78/75 is making 11-13hp/lb and takes 20lbs to get to 700, but the 88/83 makes double the hp/lb and can do 700 at lower boost which would you rather have?
The 88/83 doesn't seem to have a problem making 800+ in other cars and the 78/75 appears to be falling off at 700. I guess if 700 is the end goal then the 78/75 fits the bill for sure!
Another question... if the 78/75 is making 11-13hp/lb and takes 20lbs to get to 700, but the 88/83 makes double the hp/lb and can do 700 at lower boost which would you rather have?
#372
8 Second Club
iTrader: (4)
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Complete opposite from what I have found..... I've seen a solid 3~4 tenths and same mph at the track from pump gas switching to E85 even with same amount of boost, and timing. Only time I could see this even being close is on a lower boost setup with really cool ambient air, or a really efficient ice water chiller.
#373
8 Second Club
iTrader: (13)
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I'm not sure about a 3,700lb truck or the 78/75... but if the 78/75 flows anything like the PT7675CEA on my 4000+lb car then I would guess the 88/83 would be faster down the track off the foot brake.
I recently went through a swap from a 76/75 to an 88/83. The 88 showed no loss on the low end since they 60' the same, was quicker/faster to the 1/8th and the 1/4, ET dropped and trap speed picked up 5MPH.
#375
Launching!
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Good question!
I'm not sure about a 3,700lb truck or the 78/75... but if the 78/75 flows anything like the PT7675CEA on my 4000+lb car then I would guess the 88/83 would be faster down the track off the foot brake.
I recently went through a swap from a 76/75 to an 88/83. The 88 showed no loss on the low end since they 60' the same, was quicker/faster to the 1/8th and the 1/4, ET dropped and trap speed picked up 5MPH.
I'm not sure about a 3,700lb truck or the 78/75... but if the 78/75 flows anything like the PT7675CEA on my 4000+lb car then I would guess the 88/83 would be faster down the track off the foot brake.
I recently went through a swap from a 76/75 to an 88/83. The 88 showed no loss on the low end since they 60' the same, was quicker/faster to the 1/8th and the 1/4, ET dropped and trap speed picked up 5MPH.
#376
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Denmah & Stock48:
I see you use the Deka 80lbers a lot. Have you done any comparisons between those & the Racetronix 850's? For $500 difference I would expect some performance to be had or is that not your findings?
I see you use the Deka 80lbers a lot. Have you done any comparisons between those & the Racetronix 850's? For $500 difference I would expect some performance to be had or is that not your findings?
#377
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What size engine? Also, were these Precision turbos you're talking about, or chinese variants? (Or a Precision swapped out for a chinese?) Interesting!