For the Auto guys, supercharged b20 on MP7A JDM automatic tranny

[Spawne32]

I know that people are mentally challenged when trying to wrap their heads around an automatic honda so im just gonna lay out the basic specifications of the build, and the pics. Then everyone can feel free to comment looking forward to opening up some new doors for the automatic folks.

JDM B20B Engine Block
OEM Honda Crankshaft
Crower Steel Billet H-Beam Connecting Rods
Supertech 84.5mm 11.5:1 Compression Pistons

JDM P8R Cylinder Head Casting
33mm Intake/28mm Exhaust Valves
Supertech Dual Valve Spring Kit
Mild/Medium Hand Port and Polish (Intake/Exhaust Ports)
DDTECH Squeeler Cams (Supercharger non vtec profile)

Jackson Racing Supercharger Kit
MVM Stepper Pulley
Ported and Polished M45 Blower Case (Filled Silencer Ports)
OEM LS Crank Pulley

Private Label Manufacturing B Series Narrow Header (4-1 2.5" Downpipe)
3" Catco Catalytic Converter
3" VRS Aluminized Steel Cat Back Exhaust Piping
FloPro Baffle Pack Resonator
Solo Performance OE92 (Turbo Style) Muffler
3" Custom Short Ram Intake with 6" Blox Velocity Stack and AEM Dryflow Filter
CNC Venturi Ported 67/60 Throttle Body

ACURA RDX 410cc EV14 Fuel Injector's
Walbro 255lph HP Fuel Pump
AEM Adjustable Fuel Pressure Regulator
3 Gallon (4gph) Methanol Injection System on Devil's Own Proggressive Methanol Controller
93 Pump Gas

JDM MP7A Automatic Transmission
Raybestos GPXX Clutch Kit
Precision of New Hampton Street Stall Max 2800-3000 RPM Stall Converter

b20b back from the machine shop and ready to start building





painted the block gunmetal




crank installed and rotating smooth as butter with great clearances



mp7a picked up from JDM engine depot in north jersey



precision of new hampton street stall max torque converter



pistons installed in the block




more work










P8R head ported and polished with 3 angle valve job and backcut valves








some pics of the motor assembled with my ddtech custom regrinds

 

[XslickwhitetegX]

fun project, going to keep an eye on this thread! whats your hp goal? 180 to 200 i assume..

 

[Spawne32]

fun project, going to keep an eye on this thread! whats your hp goal? 180 to 200 i assume..

i made 180 to 200 on my car now with a stock b18b1 lol... not really doing it for anything super crazy at this point, i enjoy being unique, the supercharger is a head turner, and while it will probably only make about 8psi, the virtual engine building and cam designing programs we have been using on the setup show crank horsepower to be just above 300, so im hoping to see about 250 to the wheels. The range however can go from anywhere to 235 to 275 for it to be acceptable. Hoping that the methanol tuning puts it over that 250 edge though.

 

[XslickwhitetegX]

stock is 142 if im not mistaking, while b18c5 makes 195hp.... so your stock b18b made more if not close to a b18c5? am i missing something here or am i really that tired?

250 sounds like a reasonable goal i just hope that torque convertor hold up.

 

[Spawne32]

stock is 142 if im not mistaking, while b18c5 makes 195hp.... so your stock b18b made more if not close to a b18c5? am i missing something here or am i really that tired?

250 sounds like a reasonable goal i just hope that torque convertor hold up.

my b18b1 is supercharged on 7psi, (otherwise completely stock) im taking the supercharger thats on the car currently and transplanting it to the b20 thats all that torque converter will hold up plenty fine trust me lol ive been drag racing my car for over a year now on a completely stock 200,000 mile SP7A automatic

 

[Kyle]

What are you going to be tuned on? Does any company offer tuning for automatic ECUs?

 

[Spawne32]

sorry i was under the assumption everyone knew that im working with boost here from the get go lol

 

[Spawne32]

What are you going to be tuned on? Does any company offer tuning for automatic ECUs?

good question, as the electronics are the real monkey wrench in this whole program. If it wasnt for the fact that this car is OBD1 this build really wouldnt be possible. You have to start with a automatic car that already has independent transmission control and engine control, like the 94-95 integra's have. As far as tuning goes, the car is already tuned on ectune, and it will continue to be tuned on ectune, as its the only program that offers support to allow the torque converter lockup to engage properly. The trans computer on the opposite side of the car has been modified to allow higher shift points above 7000 rpm to make use of extra available power up to 7500 rpm. All of the engine tuning is done on a moates demon and a socketed P75 automatic ecu.

 

[speedin]

i just hope that torque convertor hold up.

Torque converters can handle ALOT. They can actually handle more than a clutch can. They will just start losing more and more of the power if you over stretch it. Thats why the higher stall converters use a more viscus fluid and a more aggressive internal vain design to help transmit the power.

Remember that bracket drag racers love built automatics... So making one handle 300whp isnt tough.



Look forward to hearing some updates on the build. I give you respect for doing things a little differently.

 

[Kyle]

So the OBD2 Integras don't have separate transmission and engine controls? That does seem very complex, I guess why did you decided to build an auto B18B? Just to be different? It just seems overly complex, but I do like the idea of supercharging it instead of just turboing it.

 

[Spawne32]

Torque converters can handle ALOT. They can actually handle more than a clutch can. They will just start losing more and more of the power if you over stretch it. That why the higher stall converters use a more viscus fluid to help transmit the power better.

Remember that bracket drag racers love built automatics... So making one handle 300whp isnt tough.



Look forward to hearing some updates on the build. I give you respect for doing things a little differently.

I appreciate the fact that someone can actually understand this, rather then just shooting it down like every other honda driver does. I just wish the aftermarket had more available for these kinds of projects, but seeing as how ive only seen a total of 3 done over the past 10 years to varying degrees, I can understand why there isnt really a single company out there that makes parts. One of the biggest flaws of this whole build that I still have to figure out is the open differential situation. Ive heard of people making the manual transmission differentials work but i have not found any in practice yet. For all intents and purposes the differential cases are IDENTICAL across the board on all honda transmissions, manual and auto alike. The only differences being that the speedo gear is not pressed on and the final drive seems to be bolted to the diff on a different position. Aside from the gearing, which isnt a HUGE deal, everything else has been dealt with regarding shift time, engagement, and loss from the converter.

 

[Spawne32]

So the OBD2 Integras don't have separate transmission and engine controls? That does seem very complex, I guess why did you decided to build an auto B18B? Just to be different? It just seems overly complex, but I do like the idea of supercharging it instead of just turboing it.

always been working with automatics, and manual transmissions never really gained any appeal to me expect for dedicated drag cars, which i havent gotten into yet, only worked with in passing from other owners. Contrary to believe, it would actually be more expensive for me to swap in a GSR or type-r manual tranny then it is to build this automatic. I dont even have 500 dollars in transmission work yet, and when its all said and done, it will still not exceed the price of a manual swap.

 

[speedin]

Didnt the JDM GSR auto tranny have a LSD in it?

If not id go shopping around 90's Honda's to find a model that had some sort of LSD in an auto trans. Knowing Honda whatever you find should'nt be too hard to get it to fit in a B trans.

 

[XslickwhitetegX]

dont think the jdm auto came with lsd

now its making more sense..haha. sounds like a clusterf*ck as far as tuning goes. I have a buddy on another fourm thats supercharged his auto for a DD and burned threw 3 different torque convertor and 1 tranny before giving up on the project. He felt only way was the levl10. this of course was 10ish yrs ago.showing my age

btw love your sig

 

[Spawne32]

Didnt the JDM GSR auto tranny have a LSD in it?

Apparently not, as thats what i have here, the only one i know of that does have a LSD in it is the JDM civic transmission M24A that came with a B16. However that transmission will not work with the computer setup that i have, and is physically smaller in both case size and drum/clutch size internally. Biggest advantage of using the integra SP7A/MP7A transmissions is the clutches and drums are much larger then any civic automatic transmission ever came with.