Will a converter built specifically for footbrake racing differ from a converter built for trans brake launches? I have a 2000 pound left steer roadster with a 650 horse bbc and pg. The converter will stall at around 5800 - pretty loose BUT, I still need it to cut a decent light and repeat for bracket racing. I’ll have the engine dyno’d tomorrow and then will be shopping for a suitable spragless converter. I could use suggestions on a company that has abundant experience with building competitive converters for footbrake racers. ETS around 5.70 @ 120mph.

Mike, this might help.

https://www.facebook.com/watch...d&v=1729563890936883

J Lamb that Larry posted offers excellent advice and I follow it. The 5800 stall you posted will probably flash to 5600 -5650 off starting line and could/ will drop after launch. When asking for stall I always request “Flash Stall” as it’s the rpm you’re looking at in the launch DA of the run.

I tried Abruzzi July 2025 first time because they advertise here on DRR. Marco hit my requested Flash Stall to within 25 rpm, and he went out of his schedule to get the converter to me in 3 days because I was broke and needed it asap without an additional charge. This is the first spragless converter that I’ve owned.

This is a pic I posted in a recent thread. This is the Abruzzi converter being used with a borrowed trans that had a 1.40 planet (top DA) because my trans was broke as well. The 1.56 planet in my new trans ( bottom DA) is what I normally run and this is the information I used for Marco to build it. I requested 6400 Flash Stall. Look at the Blue Cur1 numbers indicating Flash Stall.

There are a lot of companies that can make you a good converter. I have had best results with Hughes converters, my go to guy there is Kevin Klienweber. Stephen Hughes has also been helpful. Kevin knows his stuff and is a pretty good racer to. Tell him what you want to do and give him all your specs, HP, gear ratios, weight etc. and he will recommend converter for your needs and build it right. Kevin can answer your question about footbrake converter being used for transbrake. He may tell you yours will work as is? I tell you that because he wont blow smoke up you and sell you something you do not need. My converter worked good on pro tree transbrake and footbrake racing but I like my converters on the loose side.

Here is the difference some companies you will have to pull transmission and converter and send it back 2 or 3 times to get stall right. Hughes has got mine perfect FIRST time every time. That has saved me so much time, money and labor. I do most of my work myself and do not want to have to do it 2 or 3 times to get it right.

I'm going to second Marco Abruzzi. I bought one from him last winter and started running it early 2025. He nailed the flash I was looking for.

I also run a roadster, although it's a small block car. I'm running low to high 5.60s and mine flashes to 6050 in 4000' of humid air and 6200 in 2000' of dry air falling back 650rpm with a 6800 shift. 1.20-1.22 60' depending on the air.

I had to make some changes when I put his converter in. I was having trouble staying green. I replaced an FTI converter that was flashing 5800 or so and fall back was 800rpm and a couple hun slower in 60' but was nowhere near as consistent. I was leaving at 2800 ± with the FTI and I had to take a few hundred out with the Abruzzi to find my spot.

Marco kinda laughed when I told him I footbraked my roadster all the time because you just don't see it that often but he gave me exactly what I asked for.

Great feedback! The video was very helpful Larry. The dyno shots help visualize the event as well. I’m leaning towards Abruzzi. Off to the dyno in an hour or so. Thanks.

Not quite apples to apples . I run footbrake with a tbrake speced verter . It flashes/stalls @ 6000 . In saying that I leave quite low 1800 off foot , when I was using tbrake it was @ 4500 . Any thing under 3000on tbrake will sixty same as foot above will get faster . Plymouth is quite heavy @ 3780 .
runs 6.60/10.30s regular , has been 6.50s/10.20s
It is very consistent no matter the weather .
This is a A1 unit and when ordered told them this is regular street driven as well , drives great on interstate and local.

Tex