557 A460 heads

tis car ran like a rape ape juy 4th 2013. we pulled the converter out to fix a leak. nothing else done.... put it back in showed up for the 2013 Mile Highs and the car was slow from the very first pass. we rarely run this off the stop so i have no idea what that will fix. this car was running 9.50's with 1.42-1.45- 60 ft times and 3 seconds in the stop and we are now down to 1.65 60fts and only been running 1.5-1.6 in the timer and lost 3-4 MPH. so here what we have tried
converter
had repaired leaking converter send back and double checked over the winter and put back in at the beginning of this year
pulled the carb apart and cleaned all the circuits but never pulled the needles and seats?
checked the fuel flow (MagnaFuel 300 set at 6lbs and flows like a fire hose)
new tires
went through the trans. we lost a fitting in the shut down area and did this as a precaution (first race this year in May)
rebuilt the heads as we had 60% leakage on #1 intake installed new spring installed pressure down 50 lbs (just before this years Mile Highs)
this week end week end ran a brand new motor and a known good new msd and new wires
tach has been jumping around so we disconnected the leads to the 7AL3 and the Tach signal to the Dedenbear timer as well

I have no interference problem with linkage and have even check it over while we had the carb off this weekend as well.

Ace (LOST IN SPACE NOW)

Well it's pretty well got me stumped, since you've fixed, freshened or replaced pretty much everything that makes it go.  That's why I keep looking at stuff that's intended to make it SLOW.  When all attempts at diagnostics fail, I start deliberately changing simple things one at a time.  I'd still run it with the t-stop in the trailer, just to satisfy myself so I could think in another direction.  And I'd be damned if I'd replace the car and forget it.  That thing would bother me forever.  That's me, tho...........

who repaired the converter? if thats all you changed i'd look at it..........

cool40 wrote:who repaired the converter? if thats all you changed i'd look at it..........

the converter that worked so well was a converted bolt together buy Neal Chance and it has always had a leak at some point or another. well when we pulled it out when it was performing so well was because of a leak. my local guy unbolted it and cleaned it out to pressure test it and find the source of the leak. the repair was made inside the front cover. once we ran the converter (2013 Mile Highs) and found it was slow we talked and he built me one as we talked for 2 years about him building me one. So after the the Mile highs i installed one of his and picked up a 1/4 of a second on the timer but still a 157.00 MPH (not the 160MPH we were running. I also just found out he built it spragless)) . So after the season was over I sent the Neal Chance back to him and asked that it be looked over and converted back to a weld up as i had it with leaks. So this year we started out with that converter and it still in the car. I wonder if the sprag is slipping?

Ace

UPDATE: Been talking with my neighbor and i asked about putting a sprag back in his converter that has 18-19 runs on it. So i dropped it off Monday and Tuesday morning he called and said i had laid over the fins in the converter.    So i was thinking it was worse than what he said but he fixed it and installed a sprag and brought it over tonight and even the half that was damaged to show me and I'll be Damned. He was telling me the truth. I scratched the converter on purpose just to see what I get back and it had the marks i left on it (the damaged part) now this was the pump side that goes in the trans first. He said his vender (I think its Trans Specialties) wants it back to see what happened. he only charged me for the sprag so I'm pretty happy right now. Just need to get it in the car and test it out


Ace

   

powerstrokeace wrote:UPDATE: Been talking with my neighbor and i asked about putting a sprag back in his converter that has 18-19 runs on it. So i dropped it off Monday and Tuesday morning he called and said i had laid over the fins in the converter.    So i was thinking it was worse than what he said but he fixed it and installed a sprag and brought it over tonight and even the half that was damaged to show me and I'll be Damned. He was telling me the truth. I scratched the converter on purpose just to see what I get back and it had the marks i left on it (the damaged part) now this was the pump side that goes in the trans first. He said his vender (I think its Trans Specialties) wants it back to see what happened. he only charged me for the sprag so I'm pretty happy right now. Just need to get it in the car and test it out


Ace

Hope that sorts things out for you.

update

Well after getting the converter loosened up from 5800 to 6200 it no longer pulls the engine down at the launch. We discovered this watching the go pro videos. We don't have and data recorders. But we (I) feel that this motor has way to much cam for the elevation. This motor has better flow numbers on te heads by 20-30 cfm over the motor we started out with last year that suddenly lost HP!
Starting last year we purchased a used motor from a friend and had no all out runs till after we started having issues during our mile high race. After that we ran a few bracket races with a best ET of 8.20 @ 163 plus we even tried a few thing after that and the beginning of this year up till after the mile high race this year. I even pulled the heads days before this event and completed a valve job due to and intake valve leaking bad on #1. But after we put the heads back on warmed the motor up and re leaked down that same cylinder with poor ring seal. We went from 60% to 30% and just blowing past the rings so I'm in the process this week tearing down the motor and have a ring company that would like me to send them the ring for them to evaluate them. I was told to get a good 400 Grit finish from the machine shop and then take a 320 grit ball hone and make a 8-10 passes using that be for reassembley. This motor has bone stock unported TFS a460's and very small in my opinion cam by Cam Research ( I can't comment on this)and has ran faster than our results of this current build
This current build has only ran a best of 8.43@ 159 and change.same carb. Same throttle stop with no improvements. Again from my stand point I feel the size of motor and the fined altitude we have a missed matched cam. I even advance the cam 2 degrees with no change in ET. So I will leave this combo along for the Tim and consult with former resident of Colorado that works at Comp Cams and go over all the details
So with that said the used motor is getting a fresh ring and bearings and no changes we will leave this build alone for the winter while we are working on a HUGE (632) deal for next year.
Ace

powerstrokeace wrote:Well after getting the converter loosened up from 5800 to 6200 it no longer pulls the engine down at the launch. We discovered this watching the go pro videos. We don't have and data recorders. But we (I) feel that this motor has way to much cam for the elevation. This motor has better flow numbers on te heads by 20-30 cfm over the motor we started out with last year that suddenly lost HP!
Starting last year we purchased a used motor from a friend and had no all out runs till after we started having issues during our mile high race. After that we ran a few bracket races with a best ET of 8.20 @ 163 plus we even tried a few thing after that and the beginning of this year up till after the mile high race this year. I even pulled the heads days before this event and completed a valve job due to and intake valve leaking bad on #1. But after we put the heads back on warmed the motor up and re leaked down that same cylinder with poor ring seal. We went from 60% to 30% and just blowing past the rings so I'm in the process this week tearing down the motor and have a ring company that would like me to send them the ring for them to evaluate them. I was told to get a good 400 Grit finish from the machine shop and then take a 320 grit ball hone and make a 8-10 passes using that be for reassembley. This motor has bone stock unported TFS a460's and very small in my opinion cam by Cam Research ( I can't comment on this)and has ran faster than our results of this current build
This current build has only ran a best of 8.43@ 159 and change.same carb. Same throttle stop with no improvements. Again from my stand point I feel the size of motor and the fined altitude we have a missed matched cam. I even advance the cam 2 degrees with no change in ET. So I will leave this combo along for the Tim and consult with former resident of Colorado that works at Comp Cams and go over all the details
So with that said the used motor is getting a fresh ring and bearings and no changes we will leave this build alone for the winter while we are working on a HUGE (632) deal for next year.
Ace

If you want to share the cam specs I'm sure I can give you a lash change to get it going in the right direction.