Yellow Bullet Forums banner

1 - 16 of 16 Posts

·
Registered
Joined
·
101 Posts
Discussion Starter #1
Having some converter issues and looking for opinions before purchasing another one or getting mine changed
Combo is 438ci sbf making 750hp na spraying a 35 jet in a 3300lb car with 3.9s and 1.8 first running 1/4 mile only
Has run [email protected] on a 33 jet and [email protected] on a 35 jet
Problem im having is the converter will flash to 6000-6300 depending on how much I spray on the hit but it 60fts slower the more I spray and lugs it down about 1.3 sec out
Have spoken to converter builder who suggests loosening it to stop it lugging down, does this sound right ?
I was thinking it needed to be a little tight on the hit to stop the flairing ?
Ive tried everything from 50% gas with 4deg launch retard to 80% gas with 0 launch retard and it does nothing but flair it more at the drop of the button.
Any suggestions ?
 

·
Registered
Joined
·
6,814 Posts
Share your combo, results, & logger graph (if you have one) with your converter company, & take their advice. Lots of variables to consider like air & track conditions, fluid used, tranny gearing, power applied, tire size, rear gearing etc. Good luck.
 

·
Registered
Joined
·
773 Posts
Having some converter issues and looking for opinions before purchasing another one or getting mine changed
Combo is 438ci sbf making 750hp na spraying a 35 jet in a 3300lb car with 3.9s and 1.8 first running 1/4 mile only
Has run [email protected] on a 33 jet and [email protected] on a 35 jet
Problem im having is the converter will flash to 6000-6300 depending on how much I spray on the hit but it 60fts slower the more I spray and lugs it down about 1.3 sec out
Have spoken to converter builder who suggests loosening it to stop it lugging down, does this sound right ?
I was thinking it needed to be a little tight on the hit to stop the flairing ?
Ive tried everything from 50% gas with 4deg launch retard to 80% gas with 0 launch retard and it does nothing but flair it more at the drop of the button.
Any suggestions ?
I AGREE WITH YOUR CONVERTER GUY.
 

·
Registered
Joined
·
101 Posts
Discussion Starter #4
Share your combo, results, & logger graph (if you have one) with your converter company, & take their advice. Lots of variables to consider like air & track conditions, fluid used, tranny gearing, power applied, tire size, rear gearing etc. Good luck.
Thanks
I am working with my converter guy and have a few things to try before we pull it out
Unfortunately we don't have many NOS guys here so thought it was worth asking the question
 

·
Registered
Joined
·
232 Posts
Just a little worried it will do a similar thing just at higher rpm and also don't want it to slip anymore up top or ill probably need a gear change as well
TCE in Victoria did one for us. Lower 8 sec nitrous car. Stalled higher and slipped less. Made a big difference to our effort. Witchcraft.
 

·
Registered
Joined
·
610 Posts
Having some converter issues and looking for opinions before purchasing another one or getting mine changed
Combo is 438ci sbf making 750hp na spraying a 35 jet in a 3300lb car with 3.9s and 1.8 first running 1/4 mile only
Has run [email protected] on a 33 jet and [email protected] on a 35 jet
Problem im having is the converter will flash to 6000-6300 depending on how much I spray on the hit but it 60fts slower the more I spray and lugs it down about 1.3 sec out
Have spoken to converter builder who suggests loosening it to stop it lugging down, does this sound right ?
I was thinking it needed to be a little tight on the hit to stop the flairing ?
Ive tried everything from 50% gas with 4deg launch retard to 80% gas with 0 launch retard and it does nothing but flair it more at the drop of the button.
Any suggestions ?
Do you use Gonzo?
At the moment I've got my converter set-up for N/A but I fear it's going to flash too high with a 200 shot.
 

·
Registered
Joined
·
101 Posts
Discussion Starter #9
Do you use Gonzo?
At the moment I've got my converter set-up for N/A but I fear it's going to flash too high with a 200 shot.
Nah mate
We use TCE on everything and have had great results with boosted stuff
Im actually thinking about getting a bolt together from PTC so we can fine tune it
 

·
Gas Passer
Joined
·
4,909 Posts
What size tire? What RPM do you shift and how far down do the RPM's drop when you shift? Are you using a progressive or just hitting it with all of the nitrous at once? I agree with your converter guy, it's lugging the engine down at 1.3 seconds cause the converter is starting to grab and you're only spraying about 325-350 hp. Couple that with an engine only making 750 hp and a car weighing 3300 lbs and that engine is screaming for help. lol If your engine is designed for more nitrous, throw a second kit on it at 0.8 or 0.9 tenths and see what happens.
 

·
Registered
Joined
·
101 Posts
Discussion Starter #13
What size tire? What RPM do you shift and how far down do the RPM's drop when you shift? Are you using a progressive or just hitting it with all of the nitrous at once? I agree with your converter guy, it's lugging the engine down at 1.3 seconds cause the converter is starting to grab and you're only spraying about 325-350 hp. Couple that with an engine only making 750 hp and a car weighing 3300 lbs and that engine is screaming for help. lol If your engine is designed for more nitrous, throw a second kit on it at 0.8 or 0.9 tenths and see what happens.
28" radial , 1300-1500rpm drop depending on what rpm I shift at
Yes using a progressive which is all in by 1.2 sec
Its worse with more nitrous on the hit
Car goes 1.29 60ft with a 32 jet and 1.36 with a 35 jet and shows 300rpm more flash with the 35 jet and doesn't lug down on the 32 jet
Going to try more power earlier next weekend and see if we can get it to work a little better before pulling it out , my try leave on everything and see what it does
 

·
Registered
Joined
·
4,125 Posts
Understand but was told it will effect top end rpm as well by converter guy
A converter can have a higher stall rating off the bottom, yet lock up better on the top end when configured to do so. More slippage = more rpm, where better lockup (less slippage) = lower rpm. A lot of the really good converter guys can build them now to do pretty much anything they want, it's all in the design. Higher stall off the line will not always result in higher finish line rpm. For bracket racing, looser tends to be a little more consistent in many cases, but is still combo dependent. Different converter guys will give you different input on your stuff too. I'd suggest calling a few and just talking with them. Doesn't mean you have to buy from them, you can still use your guy, but a lot of time they have valuable info that can help.
 

·
Registered
Joined
·
4,125 Posts
28" radial , 1300-1500rpm drop depending on what rpm I shift at
Yes using a progressive which is all in by 1.2 sec
Its worse with more nitrous on the hit
Car goes 1.29 60ft with a 32 jet and 1.36 with a 35 jet and shows 300rpm more flash with the 35 jet and doesn't lug down on the 32 jet
Going to try more power earlier next weekend and see if we can get it to work a little better before pulling it out , my try leave on everything and see what it does
That's a pretty big rpm drop, way too loose. You need something quite a bit different.....
 
1 - 16 of 16 Posts
Top