904 Flares on 2-3 shift?

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Valvebounce

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My apologies if this has been thrashed out before,
But we have a 904, bought from a reputable shop. It's a full manual valve body "drag free" (What ever drag free means?) 904. Supposed to be a pretty good unit. According to the shop who supplied it.
However when I'm racing, and really have the boot up it it flares on the 2-3 shift. The obvious answer would be go back to the seller. but they're in the USA, and we're in New Zealand.
Plus I've never had bad advise on this forum yet. Trans has done maybe 1500 miles, and about 30 passes since it was installed two ish years ago. I'm starting to get the hang of driving the car now. so it's really bugging me. (I used to think I was knocking the shifter too far and hitting N, since it still have the column shift.

Thanks in advance.
 
I would do a pressure check, and then check in the trans pan. Sounds like the high gear clutches are bad. Had a rebuilt one do the same thing years ago, the clutches in the rebuild kit were bad. Put new clutches in and it was fine
 
Was it fitted with a lower gear set from an A-999 or the like? Reason I ask is that sometimes there can be some clearance issues with overall length of clutch packs and gear sets that will delay or prevent lockup of direct clutch pack. You can research it here on FABO on 904 tech pages.
 
Pressure check like Sterling said. If the pressures look good check the front band adjustment. If it's real loose it can let it flare on shifts (all). If band adjustment is good time to come out and apart for inspection. They may have nicked a high clutch seal when rebuilding it. Most likely you'll find the high clutch burned since you've been driving it this way for a while. Could also be what Garrett said
 
"Drag free" probably means it does not have gear braking which would mean it does not have front band apply in low gear. That's not the best for a race only car. Sounds like you are going to have to tear into it.
 
Actually it’s the rear band that would not have band apply. If the 2nd band didn’t apply u wouldn’t have 2nd gear. If it had front band apply in low it would lock up and not move. Is this forward pattern or reverse pattern. Kim
 
Actually it’s the rear band that would not have band apply. If the 2nd band didn’t apply u wouldn’t have 2nd gear. If it had front band apply in low it would lock up and not move. Is this forward pattern or reverse pattern. Kim

I don't know why I threw front in there. I know damn well low and reverse are on the same band.
 
Aren't some of those full manual valve bodies required to have the kd hooked up?

If this the case? It's no biggie to refit that.

I only drive the car on the strip. I'll have to ask the owner if he's noticed it driving on the street too.
Should probably email the shop who built it too. (no doubt he'll be doing that, but I thought I'd ask you guys too) The car certainly goes well. Even with that little flare it's run 12.5@107.
 
Some valve bodies still need the kd linkage. Or u could tie it back with safety wire. What brand is the mvb? Talk to the manufacturer. Kim
 
I think we do need to talk to the guys who built the trans. They're a reputable firm, with many many glowing reports on the www.
I also googled my problem and found a number of similar threads. (Most on this site! Haha.)
 
I do that often, the google search is more bot oriented so it will put you right to a thread on here to review. If it's Mopar oriented, it is probably on here at least in two postings! That is an excellent thing, I think that this forum is probably one of the most intensive and reliable sources of experience based information available ANYWHERE on the W.W.W.
 
im having the same issue and just noticed it this over the week end shifting form 2-3 4k shifts nice over that like you get a little neutral sound before going into 3rd. Just had this 904 built with the Turbo action fmvb early march.. I hope its only a band adjustment as Fishy68 mentioned. New steels and clutches , bands and some hard parts i supplied.
 
Will check tonight, funny when I had it done and got it home checked the trans level and it took 1 pint to top it up, since then I have put on around 3000ks but will check it again . This just happened on Sunday so I hope there’s no damage been done.
 
They'll do that if the fluid is a little low. Checking running in neutral?
Thanks Cuda checked fluid this morning as weather here has been pretty ordinary all week got a break this morning and took the car for a run checked fluid after some run time to get it all up to temp it was on the low side needed to add 1/2 litre , shifts feel crisp 3-3500rpm. Will test again later in the week @ 5-5500rpm .
 
@oldkimmer the valve body I’m using is the Xtreme Action 17876XA which doesn’t require the KD tired back at all. I haven’t had a chance to get it back out as we are in Stage 4 lock down due to Covid and you need to be careful to not get caught driving around unless going to the doctors etc otherwise your donating to the government. ! Police are like Nazis at the moment .
 
Haha Melbourne is virtually shut down not a real lot happening. A lot of businesses are closed curfew after 8pm . 5 more weeks of this ain’t good for anyone.
 
@CudaFactHackJob got the car out this morning warmed everything up real good than launched from a 5300rpm hit no flare 1-2 2-3 . Pretty stoked as it was only a little low on the fluid which was causing the 2-3 flare. Topped up 1/2 litre problem fixed . Thanks on the advise
 
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