13b rotary LPG brute ute ( b2000 )

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bumpstart
Posts: 133
Joined: Wed Jan 20, 2010 9:09 pm

13b rotary LPG brute ute ( b2000 )

Post by bumpstart »

here is a little snip of some first start footage of something i have been doing for a mate
its a 13b engine,, using an unusual combination of end plates with some porting , fitted with a turbo,, all in a mazda b2000 ute
genuine examples of b1600 utes with factory 13b where sold in the mid 70's in the USA , known as REPU's


NB
i have a similar turbo LPG and ignition setup on my daily user FC rx7
http://www.youtube.com/watch?v=r1jl7dXI7Yw
been waiting nearly six months for it to come back from gas fitter
they couldn't work it out and some of the f/ups at that end where laughable

i got it going after 6 hours effort,, 1st tug ,, and this is the first key start vid
-still very rough on the mixes and setup and motor build is 3 mins run time new
[ so far i have a vac leak on the lower inlet manifold ]

i built and supplied the engine
the rotor conversion ( 12a rx7 front engine bracket and s4 spark side feet welded on to full chassis )
turbo fit and dump pipe
intercooler fit ( supra under the guard)
driveline ( modded s5 turbo box and custom tailshaft )
and wiring ( including partial locked curve dizzy and DLI ignition )

the shop got the radiator
exhaust ( after dump pipe )
gas fit up
battery fit
and supply two intercooler pipes
( the two shit bent ones in the bay )
[ and took 6 months with that ]

this engine is a RESI 6 port,, tall port primary ,, with rx4 rotors
the LPG system is custom plenum, VN TB, impco 225 and model E converter

the turbo will be s4 highflow after run in


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turbo s5 LIM , custom plenum for single 65 mm TB
port matched to 6 p block

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ports and housings

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cross port end plates on the secondary /auxiliary ports

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old anchor

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engine mounts

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s5 turbo gearbox mods

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engine built and ready to fit

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engine in

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RHD makes things tight
when the going is hard, don't retard, remember your lubrication

bumpstart
Posts: 133
Joined: Wed Jan 20, 2010 9:09 pm

Re: 13b rotary LPG brute ute ( b2000 )

Post by bumpstart »

286 rwhp on a DD dyno at 13 psi
( s trim baby hybrid turbo )
when the going is hard, don't retard, remember your lubrication

Steptoe
Posts: 1504
Joined: Fri Feb 02, 2007 8:32 pm
Location: JAFA , New Zealand

Re: 13b rotary LPG brute ute ( b2000 )

Post by Steptoe »

My son, like u highly miss giuded :roll: :D has been watching this thread...
He is a rotary man...did his own rx7....
Between u and I and for a rota of cause...a nice job.
The volumes that go thru the engine would not the 225 limt things some what? even a 425.
I was doing a few numbers ages ago and the rotary turns simiar to a V8
Would not, duel 425s or injection be the way to go?
My Spelling is Not Incorrect...It's 'Creative'

bumpstart
Posts: 133
Joined: Wed Jan 20, 2010 9:09 pm

Re: 13b rotary LPG brute ute ( b2000 )

Post by bumpstart »

a 425 was originally part of the original idea but i was lead to believe they are not as boost friendly or as simple as the 225 , or as happy when used in a horizontal install onto EFI TB

the 225 isnt all that far off that of the airflow of the stock carbs used on early rotors ( 329 CFM V 315 CFM )
and under 1 bar boost that 329 CFM is going to be 650 + CFM

under boost the restriction wouldn't amount to any more than was already had from the binned stock mazda intercooler
so it was decided to err smaller to keep throttle response knowing i had an approx 320 HP limit with a single E and lockoff

225 also have 2.25 and 2.5 inch inlets ( depending on which cover ),,
and the massive mazda s4 Tb has a a 2.25 inch stock entry to the hat , and can still make decent power through that



had a four barrel manifold been used on an NA engine then a 425 would definitely be a better option
but under boost the 200/225 have the nod for easy hook up to the EFI manifolds without really being the bottleneck they appear on paper
( as proven by the dyno result,,, S trim s4 highflows on petrol 13bt's rarely make 280+ rwhp )







impco 225= 329 CFM , impco 425 = 460 CFM

mazda 12a nikki carb , 315 CFM, 13b hitachi carb ,, around 320 CFM,
max NA HP i have seen from these = around 140 rwhp

s4/5 13b EFI TB = 651 CFM
= 4770 mm2 staged throttle body, 3 x 45 mm
( s4 and s5 rx7, NA and turbo )

holden / GM 3.8L V6 ( used on the ute and previously on my rx7 )
= 2826mm2 single 60mm TB =about 520 CFM
when the going is hard, don't retard, remember your lubrication

bumpstart
Posts: 133
Joined: Wed Jan 20, 2010 9:09 pm

Re: 13b rotary LPG brute ute ( b2000 )

Post by bumpstart »

PS
have helped out with a "profire" custom programmable vapour injection system that uses 4 large keilin injectors and they are maxed at around 60 rwhp each ( 240 rwhp ) :|

in aus there is some red tape/ patent shit that is blocking the viability of liquid injection systems
-esp. politics about some of the cold start requirement means they must retain dual fuel and other complexities that make them too much headache to be a choice
( unfortunately )
when the going is hard, don't retard, remember your lubrication

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