Automatic Transmission 2-Speed thru 10-Speed GM Autos | Converters | Shift Kits
Sponsored by:
Sponsored by:

Hitting the rev

Old Dec 4, 2007 | 10:02 PM
  #1  
408lq9's Avatar
Thread Starter
9 Second Club
 
Joined: Sep 2007
Posts: 34
Likes: 0
Default Hitting the rev

My car has a 400 trans with a 3.73 gear and it wants to get on the rev @ the 8 mile point. it did it three times, does it sound like converter slipping or wrong rev setting in the computer. spraying 100 from tha hit and 150 in second gear. the car was just computer tuned before i went to the track.
Reply
Old Dec 4, 2007 | 10:26 PM
  #2  
performabuilt's Avatar
LS1Tech Sponsor
15 Year Member
Liked
Loved
Community Favorite
iTrader: (25)
 
Joined: Aug 2006
Posts: 10,854
Likes: 80
From: BLOOMSBURG PA
Default

400 Auto ?
__________________
Built..PerformaBuilt..Tough

Call 888-744-6542


Reply
Old Dec 5, 2007 | 09:09 AM
  #3  
408lq9's Avatar
Thread Starter
9 Second Club
 
Joined: Sep 2007
Posts: 34
Likes: 0
Default

its a 400 auto
Reply
Old Dec 5, 2007 | 09:11 AM
  #4  
b00sted's Avatar
TECH Fanatic
20 Year Member
iTrader: (7)
 
Joined: Jun 2005
Posts: 1,109
Likes: 0
From: Chicago
Default

th400's aren't computer controlled...

Why not just manually shift it?
Reply
Old Dec 5, 2007 | 09:24 AM
  #5  
Gilbert@Ace Racing's Avatar
FormerVendor
 
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Default

SO basically, it is hitting the RPM limiter at the trap, right?


What is the tire size are you running?

And what is the RPM limiter set at?

g
Reply
Old Dec 5, 2007 | 10:19 AM
  #6  
408lq9's Avatar
Thread Starter
9 Second Club
 
Joined: Sep 2007
Posts: 34
Likes: 0
Default

i'm running 1/4 mile. it has a 325 drag radial. and i know a 400 does not use a computer, i manual shift. rev is set @ 7200 on a 408ci motor. it has a ptc street/strip 3500 converter in it now and its about 6 years old.
Reply
Old Dec 5, 2007 | 10:22 AM
  #7  
b00sted's Avatar
TECH Fanatic
20 Year Member
iTrader: (7)
 
Joined: Jun 2005
Posts: 1,109
Likes: 0
From: Chicago
Default

You made it sound like the computer was 'set to shift it'. What are you shifting at? Is it slipping or flaring when you try to hit 3rd?
Reply
Old Dec 5, 2007 | 11:29 AM
  #8  
Gilbert@Ace Racing's Avatar
FormerVendor
 
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Default

Ok I get it now. After it is in 3rd at 1/2 track it is on the limiter.

What is the fluid condition?

Is the tranny new?

You may have a direct clutch slipping. And you may also be blowing through the converter. I recommend taking it to a Professional and having them take a look at the tranny.

g
Reply
Old Dec 5, 2007 | 11:38 AM
  #9  
408lq9's Avatar
Thread Starter
9 Second Club
 
Joined: Sep 2007
Posts: 34
Likes: 0
Default

it don't matter how you read it, i said COMPUTER REV, not computer shift. it's not slipping, it feels like a good pass when shifting each gear. i was just told it could be running straight through the converter on nitrous. don't know if it does that on motor because i don't run on motor.
Reply
Old Dec 5, 2007 | 12:12 PM
  #10  
Gilbert@Ace Racing's Avatar
FormerVendor
 
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Default

Sometimes the written word can be interpreted in a few different ways.

Based on the last comments then I agree... it is "running straight through the converter" then that is probably what is happening. Especially if it is more than a few years old and has been hammered on.

What 60' times are you seeing with this combo?

g
Reply
Old Dec 5, 2007 | 01:53 PM
  #11  
408lq9's Avatar
Thread Starter
9 Second Club
 
Joined: Sep 2007
Posts: 34
Likes: 0
Default

1.43 to 1.47 on 100 hit from the gate on drag radials leaving @ 3000-3200 rpm foot brake
Reply
Old Dec 5, 2007 | 02:36 PM
  #12  
Gilbert@Ace Racing's Avatar
FormerVendor
 
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Default

I am going to go out on a limb here and say that your engine is 550 fwhp without the juice. 650 with.

I think the converter stall is correct, but is worn out. Swap converters, service the tranny and run it!

g
Reply
Old Dec 5, 2007 | 03:08 PM
  #13  
408lq9's Avatar
Thread Starter
9 Second Club
 
Joined: Sep 2007
Posts: 34
Likes: 0
Default

motor made 498rwhp, but we took alot of timing out for the juice. 448 on motor and 719 on spray.
Reply
Old Dec 5, 2007 | 03:36 PM
  #14  
Gilbert@Ace Racing's Avatar
FormerVendor
 
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Default

Nice engine.

I know you leave on the foot brake but..... Does the 400 have a brake?

Either way, what is the stall speed it flashed to on the hit?

g
Reply
Old Dec 5, 2007 | 03:53 PM
  #15  
408lq9's Avatar
Thread Starter
9 Second Club
 
Joined: Sep 2007
Posts: 34
Likes: 0
Default

no brake. i really don't know, i'm focused on the light and when to shift and spray second kit.
Reply
Old Dec 5, 2007 | 04:03 PM
  #16  
Gilbert@Ace Racing's Avatar
FormerVendor
 
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Default

I get it, like a good buddy of mine who runs a 4oo shot on a Ford small block says....."When the **** hits the fan who is watching a tach anyhow, it either feels right and runs the number or it doesn't! "

I'm gonna hang with my comments and what your friend said... put a converter in it and run it. Then let us know how it does.

If you would like to discuss some options give me a call. We build racing converter and could put one toghther that you would be very satisfied with.

g
Reply
Old Dec 5, 2007 | 04:26 PM
  #17  
408lq9's Avatar
Thread Starter
9 Second Club
 
Joined: Sep 2007
Posts: 34
Likes: 0
Default

have you done work for extreme horsepower out of north richland hills. what kinda converters do you sell and what would you recommend.
Reply
Old Dec 5, 2007 | 04:39 PM
  #18  
Gilbert@Ace Racing's Avatar
FormerVendor
 
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Default

My shop is situated immediately next door to Xtreme. 15 minutes ago I was next door discussing a 700r4 build with Arvil for a mutual customer, they are building his LS1 for his '91 Corvette.

My recommendation, based on what you have mentioned here and without knowing the car would be either a 10" or a 9 1/2 converter. Because you spray it we need to put a balloon plate on it and tig weld all of the fins. There is no doubt in my mind that we can build you a converter that will get the job done. That unit would run right at $900.00. We can determine the stall later as we move through the process.

My converter builder is a racer himself. He owns an Altered that runs 5.7xx's, his wife drives a 2nd gen F-body that runs mid 6.xxx's herself. He is building a Vega with a 502 Shaffrof engine to run in IHRA Divisional Stcok Bracket classes next year.

When it comes to racing converters. We get it.

Lemme know if you are interested. I'll be here until 7:00 or so tonight if you would like to call.

g
Reply
Old Dec 5, 2007 | 05:32 PM
  #19  
408lq9's Avatar
Thread Starter
9 Second Club
 
Joined: Sep 2007
Posts: 34
Likes: 0
Default

arvil told me a shop next to him rebuild my converter for $400. the converter was never touched. i called him back later after i drove the car and asked about the converter he said it was done so i left it at that. they build me a iron block 408, but could not get the car to idle. i own the black 98 firebird.
Reply
Old Dec 5, 2007 | 06:46 PM
  #20  
Gilbert@Ace Racing's Avatar
FormerVendor
 
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Default

Well I am glad to know that.

When was this done?

When you say it was never touched, please be very specific. Does that mean that the converter was not sent out by Xtreme? Does that mean that there was no difference in the performance?

Honestly, I do not remember your car, mainly because I see too many, but I believe that my shop did not do any work on yours. Maybe the converter.

PLease call me. I am at the shop now. I would like to discuss this matter in detail with you. I know of no converters that my customers are disatisfied with. If we built it originally and the stall is not right then all we ask is for the customer to get us the converter and we'll adjust it at no cost.

We need to talk.

g
Reply

Thread Tools
Search this Thread

All times are GMT -5. The time now is 10:12 AM.