RowJ

Many hear a sales pitch...I hear good usable info.

IIMO, there are two reasons why you hear few raves about BD's twins....
1- Most dismiss them without looking closely for the very reason John Todd mentions above -bad information! "The primary turbo is not big enough" ... according to many!

2-IMO - BD mis-marketed their twins. They went after a market that could have twins without doing head work and still get 500 hp. This approach probable made sense 2 yrs ago, but in fact, missed the mark. They went after a market that was shifting it's focus from 450 hp to 650 hp. I don't think they saw what was coming...but who did??

I almost ignored BD's twins, myself. My goal was the best 600 hp daily driver I could build. But, I was so impressed with BD's twins being engineer/computer designed that I was willing to detune my truck, if need be, to use them.

I was very pleasantly surprised to see these, so called small, twins support my present HP level beautifully. They spool faster than a stock HX-35, and at WOT, EGT's will very slowly climb to about 1450* at around 110 mph. On the road...they never get in the red, on my set up.

How could BD accomplish these numbers with a S300 primary turbo, when so many of us dismiss them as 'towing twins'? Maybe those interested in understanding the complicated interaction of compound turbos might want to pay closer attention to what John has to say instead of dismissing it as promotional hype.

RJ

Rods

. But, I was so impressed with BD's twins being engineer/computer designed

Keating shealy designed the BD twin kit in his shop in TN yrs ago and sold the turbos to them through EEP now they have changed a few things mainly turbos and such as for CPU engineer goes its called blacksmith designed

Ph4tty

BD does have some maps availible. Not very detailed but here ya go:
http://www.bd-power.com/ram/graphs/b..._com_graph.pdf

Forrest Nearing

what are your drive pressures like?

wildmanben

Do you have a turbo like that? I sure could use one.

Jetpilot

Wish we did......

RowJ

45 psi @ 55 psi boost
53 psi at 60 psi boost
65 psi @ 65 psi boost... everything on full (632 hp)

'Rods' - I believe (was told) John Todd is the one primarily responsible for the BD twins of today. He is an engineer by trade and was hired away from Holset by BD.

RJ

Jetpilot

632 RWHP with Mach 4's? Something doesn't appear right with that..... Even queezing on the alcohol that number seems high. What brand and model dyno was it?

RowJ

Mustang 250.... on two separate occasions. 628 & 632 (with F-1 Springs). I have seen dyno sheets on a 730 hp Duramax from this dyno and a Dynojet that were almost identical, FWIW.
I use Racing Methanol - 50/50% as recommended to me by Jim Fulmer.

It's hard to believe but there are not many Dynojets in the Dallas or OKC area. The two I have found are in 'ricer' shops and they really don't seem to want/need diesel truck business.

The N. Texas DTR Club finally set up a Dynojet (248C) for Feb 3rd. I'm anxious to see any difference as well. According to what I read from Dave Dunbar, HP will be close but torque on Mustangs reads 150 - 200 ft-lbs high??

Anyone else tried both?

RJ

Jetpilot

Well thats an awesome number..... Normally we would need some larger sticks and turbos to see that kind of number! Great job.

Doug

RowJ

Thanks, Doug ..... but we'll see. I have always felt the numbers were a little high for the bombs I have. Anxious to compare on a Dynojet.

FYI - When I added the BD twins (nothing else), I gained 56 hp on the dyno. Previously at 572 HP, with a 'Lil' HX-55 I had on there.... the one you and I once talked about. You were very kind...and very right about that one!

RJ

kantdrive55

True on our 02 Dodge we did run the EEP twins. That was before we had John Todd working here. These kits are no where near the same design other that the fact there is two turbos and some piping. This is in no way a nock at EEP twins.

kantdrive55

http://www.bd-power.com/ram/graphs/b..._com_graph.pdf

Here is a link to the Map for our turbos.

dieselfan

how much longer till the other twin setup is released and approximately
how much?

Forrest Nearing

those are some impressive numbers! what's your peak EGT with everything on kill? sorry in advance i fyou said and I missed it