1/8th mile shakedown

JSM

Active member
Re: 1/8th mile shakedown

There will be a point at which when you reach X boost, the turbo will be ready to go and over the spool up hump. Looks like your taking things slow, and moving in the right direction. Perfect way to approach it.
 

Aeroking

e.i.
Re: 1/8th mile shakedown

TwinTurboV8Ty said:
There will be a point at which when you reach X boost, the turbo will be ready to go and over the spool up hump. Looks like your taking things slow, and moving in the right direction. Perfect way to approach it.

your absolutely right, as always. once i hit 8psi or so. the turbo pretty much spools itself.

i've noticed another thing. at WOT halfway thru 4th gear, the boost starts to fall off. hmmm
 

sy#2921

BAMF
Re: 1/8th mile shakedown

if you are using the stock boost selinoid up the duty cycle in the higher rpm's to maintain boost
 

Tooky

Serious about performance
Re: 1/8th mile shakedown

Aeroking said:
i've noticed another thing. at WOT halfway thru 4th gear, the boost starts to fall off. hmmm
Middle of 4th gear? Like around 120-130 MPH? Is the turbo a 74 or 72, I recall it was a 74 but your sig says 72 now?
 

Aeroking

e.i.
Re: 1/8th mile shakedown

Tooky said:
Middle of 4th gear? Like around 120-130 MPH? Is the turbo a 74 or 72, I recall it was a 74 but your sig says 72 now?

its a 72

and yea, i stopped checkin the speedo at when it shifted to 4th, so it might've been 110-120 somwhere
 

CLONE

New member
Re: 1/8th mile shakedown

Aeroking said:
your absolutely right, as always. once i hit 8psi or so. the turbo pretty much spools itself.

i've noticed another thing. at WOT halfway thru 4th gear, the boost starts to fall off. hmmm

Have you checked to see if the compressor wheel is hitting the cover?
 

Aeroking

e.i.
Re: 1/8th mile shakedown

CLONE said:
Have you checked to see if the compressor wheel is hitting the cover?

i'll have to pull the radiator out to get the air filter off.
I'll try tonight.
 

WyoSyclone

Active member
Re: 1/8th mile shakedown

We had found on Syclone0209's Sy that his air filter (unsupported), connected to his cobra was flexing towards the rear of the car and causing the cobra to collapse, shutting off air flow... you might just want to double check that if yours is set up with just a filter off of the cobra...

Aeroking said:
i've noticed another thing. at WOT halfway thru 4th gear, the boost starts to fall off. hmmm
 

Aeroking

e.i.
Re: 1/8th mile shakedown

i did a test launch at 4psi. i sat WOT on the converter for 9 seconds.

sec 1 - 2100@100kpa to 2300@106kpa - 14.7afr
sec 2 - 2300@106kpa to 2400@111kpa - 14.7afr
sec 3 - 2400@111kpa to 2400@114kpa - 15.1afr
sec 4 - 2400@114kpa to 2400@115kpa - 15.1afr
sec 5 - 2400@115kpa to 2500@118kpa - 13.9afr
sec 6 - 2500@118kpa to 2600@121kpa - 13.1afr
sec 7 - 2600@121kpa to 2600@124kpa - 12.9afr
sec 8 - 2600@124kpa to 2700@126kpa - 12.8afr
sec 9 - 2700@126kpa to 2800@129kpa - 12.7afr
 

Aeroking

e.i.
Re: 1/8th mile shakedown

ran the 1/4 this evening. ran 4 consistant 13.7s @ 100mph.

i did my first run on my current AFRs, next run i went .50 AFR leaner. the next run i ran the AFRs .50 richer then the first run (1.0 richer then the 2nd run).

no change in times, or mph's.

i've noticed 2 problems. First my obvious of trouble spooling on the line. i've been launching at 110-115kpa. and cant break anything above that. I've launched at 14.2AFR, then 13.6AFR, with no change.

2nd problem is my trans is built to shift at 5500rpms. but for some reason my engine wont rev that high. it revs to 4800-5000 and flatlines for a second or more, then shifts, and flatlines the rpms again for a second or 2 before it shifts again

any ideas on the shifting rpm issues?

boost didnt fall off on the far end. the turbo quiets down in 4th gear, but the boost is still there.
 

dgoodhue

BuSTeD 4.3
Re: 1/8th mile shakedown

Aeroking said:
ran the 1/4 this evening. ran 4 consistant 13.7s @ 100mph.

i did my first run on my current AFRs, next run i went .50 AFR leaner. the next run i ran the AFRs .50 richer then the first run (1.0 richer then the 2nd run).

no change in times, or mph's.

i've noticed 2 problems. First my obvious of trouble spooling on the line. i've been launching at 110-115kpa. and cant break anything above that. I've launched at 14.2AFR, then 13.6AFR, with no change.

2nd problem is my trans is built to shift at 5500rpms. but for some reason my engine wont rev that high. it revs to 4800-5000 and flatlines for a second or more, then shifts, and flatlines the rpms again for a second or 2 before it shifts again

any ideas on the shifting rpm issues?

boost didnt fall off on the far end. the turbo quiets down in 4th gear, but the boost is still there.

Your shift RPM's will go up with more torque and HP. I not sure what going on with the shifts hanging for a second. I am no transmission expert.
 

CLONE

New member
Re: 1/8th mile shakedown

If you want a different set of eyes to look at everything with your truck just let me know, I'll have time this weekend.
 

Aeroking

e.i.
Re: 1/8th mile shakedown

CLONE said:
If you want a different set of eyes to look at everything with your truck just let me know, I'll have time this weekend.

alright. give me a call later this week. and i'll come up.


wasnt the best track conditions either. also, the lights were malfunctioning, so we were running a pro-tree. lol, lots of fun. :tup: as long as your not a turbo truck trying to spool at the line.
 
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sy#2921

BAMF
Re: 1/8th mile shakedown

Dont let the lights throw you off your game. I run pro tree at my track normally since they end up getting more runs than the other test and tune. I still just sit there once the tree drops until I am ready to leave
 

denny

Active member
Re: 1/8th mile shakedown

Aeroking said:
ran the 1/4 this evening. ran 4 consistant 13.7s @ 100mph.

i did my first run on my current AFRs, next run i went .50 AFR leaner. the next run i ran the AFRs .50 richer then the first run (1.0 richer then the 2nd run).

no change in times, or mph's.

i've noticed 2 problems. First my obvious of trouble spooling on the line. i've been launching at 110-115kpa. and cant break anything above that. I've launched at 14.2AFR, then 13.6AFR, with no change.

2nd problem is my trans is built to shift at 5500rpms. but for some reason my engine wont rev that high. it revs to 4800-5000 and flatlines for a second or more, then shifts, and flatlines the rpms again for a second or 2 before it shifts again

any ideas on the shifting rpm issues?

boost didnt fall off on the far end. the turbo quiets down in 4th gear, but the boost is still there.

As for spooling off the line, I am having similar issue with the T72.
http://www.syty.net/forums/showthread.php?t=60500
I haven't try removing timing yet, haven't drove it since. In a few weeks when it get cooler I will start at it again.

You can see it didn't launch for *hit on my last 11.8 run. (1.9 60')
http://www.youtube.com/watch?v=_-bnMnRnqqk

For me, the boost fall of about 4-5lb when the TC lockup. To fix this, I am going try retarding timing where the RPM and boost at lockup. Also going to raise the shift point via the shift governor, shifting at 5100 going try 5500.

Keep posting your progress.
 

beastmode

New member
Re: 1/8th mile shakedown

Sucks your PRP got cancelled... Quaker is a fun track for just running but if you want a real time forget about it
 

Aeroking

e.i.
Re: 1/8th mile shakedown

sy#2921 said:
Dont let the lights throw you off your game. I run pro tree at my track normally since they end up getting more runs than the other test and tune. I still just sit there once the tree drops until I am ready to leave

i didnt try to beat the tree, my R/Ts were hi 4s and 5s.

i was looking thru TP, and see this "RPM above which fuel type determined high" does this have anything to do with the revs not going higher?
 

dgoodhue

BuSTeD 4.3
Re: 1/8th mile shakedown

Aeroking said:
sy#2921 said:
Dont let the lights throw you off your game. I run pro tree at my track normally since they end up getting more runs than the other test and tune. I still just sit there once the tree drops until I am ready to leave

i didnt try to beat the tree, my R/Ts were hi 4s and 5s.

i was looking thru TP, and see this "RPM above which fuel type determined high" does this have anything to do with the revs not going higher?

His Sy is one of the slowest spooling truck I have ever seen.
 
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