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B230F +T Safe Boost

corey_mck

New member
Joined
Mar 2, 2015
Location
Frostburg, MD
So I'm in the middle of pulling all the turbo bits off an 89 760 turbo I bought for way too cheap to put on my 86 244 w/ M46. I've decided to go +t on the 240 instead of swapping because I'm using the car for rallycross and I think the better throttle response and quicker spool of the higher compression engine will suit my needs better. The 240's engine only has 149k miles as opposed to the 225k on the 760. The 760 has a build date of 9/88 and is LH 2.2 and has the Garrett T3 (most of this info is for someone else's future reference)... I got lucky with a simple swap. I plan on moving over all the turbo bits, feeding oil from the sender, draining into the oil pan, and using the 760's fuel rail, FPR, injectors, intercooler, ECU and timing computer.

A couple questions for those who have done this before. How much boost can I safely run on the B230F without running lean up top and without detonating? Has anyone here done this with a knock light and wideband and knows for sure? I know these engines are a dime a dozen but I'd like to avoid popping it. I don't feel like I need to make any more than 250hp in this engine, and I'm fine with whatever it makes safely until I go MS.

Thanks in advance!
 
quality of fuel dictates timing and boost. You will need to adapt the lh 2.2 ezk to get very far with it. If everything is in good mend and you've got quality 93 available, you ought to be able to reasonably run between 10 and 14 without any shenanigans.
 
I'm running 8 according to the cheap ass sunpro guage in my dash. ****s leaking, I need to put in another new valve cover gasket and increase the flow from my crankcase vent system some how without putting it back into my engine.

I'm LH2.4 with Mikes chips and I feel like 8 psi on my +t makes my transmission want to die.
 
I've put over 70k miles on a +T running about 8psi on a 13c. It's my daily driver, a '92 240. I always use 93 octane. It could be faster...but I don't want to break it, so it's 8psi.

In contrast, we race 24hr lemons with a B230F seeing up to 14psi. It pounds around a race track for 14.5hr per race weekend, seeing up to 6200rpm and it never seems to mind. Using stock LH2.4 computers, 93 octane, stock T3 from a 240, stock late intercooler, 850 turbo injectors...really nothing fancy. So you CAN use more boost. Just have to be aware of what's going on. We also monitor AFRs with a WB02, so when something has gone wrong (usually fuel delivery), we realize it and don't abuse it.
 
Thank you guys for the input! That's exactly what I was looking for. Right now the car isn't even titled, and once I bump classes and put actual rally treads on it isn't going to see much street use at all. I'm hoping to keep it safe around 11 lbs right now.

Next question... How awful is this cast block to drill and tap? I'm getting ready to drop the oil pan, and I figured I can drill the pan or the block with the pan out and a shop vac underneath. I sort of like the idea of the block instead of the pan.
 
The factory turbo cars drain to the block. Your non turbo block has a boss casted into the side (right below the exhaust manifold). You can drill and tap that to make it drain just like a factory turbo.

I like the idea of draining to the block because it's higher up and looks cleaner, but drilling the pan has no I'll side affects that I've noticed.
 
I've been running 12psi on my +T for 5,000 km now. Has LH 2.4 and never seems to knock on chevron 94, doesnt appear to run lean, tailpipe has a light coat of soot on it, as do the plugs. No issues with this setup.
 
Thank you guys for the input! That's exactly what I was looking for. Right now the car isn't even titled, and once I bump classes and put actual rally treads on it isn't going to see much street use at all. I'm hoping to keep it safe around 11 lbs right now.

Next question... How awful is this cast block to drill and tap? I'm getting ready to drop the oil pan, and I figured I can drill the pan or the block with the pan out and a shop vac underneath. I sort of like the idea of the block instead of the pan.

I drill and tap. It's easy with the block on a stand. Probably a PITA in the car. I would tilt the engine upright and drill it since the mounts will be loose anyway.
 
Hmm Yeah, heat is the problem with all of that-- external BIG oil cooler helps. use the exhaust valves from the turbo-- sodium filled, they can take more heat. bigger oil pump? the one from 95 onward-- and and and-- it's a nearly endless list of "must do"-- below is as far as I went, and I am turning out about 200 hp wheel, enough for me, and no headaches!
 
Because it does. Full throttle shifts on an aw70 with boost will murder it.

+1 killed my aw70 with 8 psi after 3 months of beating on it. My aw71 with the accumulator mod held 8-12 psi daily for a year until I parked the car. I must have added 70k with the +t at 10psi at 360k miles it was just done.
 
Lol, I have an m47.

I'm ****ed.
Depends on boost. :e-shrug: I put ~70k on a +T with M47. M47 died from oil leaking out. :roll: It handled the torque of 8psi from a 13c just fine.

I ran 13.9@100 in my autocross 244 with an M47. It might have broken eventually, but I swapped it for a T5 instead. I was careful with shifting, though.
 
Lol, I have an m47.

I'm ****ed.

Just don't load the car up with your friends and a big cooler of beer or try to dyno the car and you'll be fine. My M47 started whining badly after I filled the car with tools and parts and drove it in I95 traffic around DC, boosting around 12psi. Before that I've autocrossed it, and general shenanigans without damage, 3rd gear is the fussy one about shifting I believe.
 
No need for 93 on stock boost from a 13c. 87 works just fine.

That said, I'm building a hybrid T3 planning to run 10-15psi and I plan on running 93 (although I may see if I can get away with 89 :ninja:)
 
So I ordered oil feed and drain stuff, but ordered a 5/8 Barb for the drain. Is that big enough? I saw some guys saying 1/2", but some DSM guys swear you need 3/4" for the T3
 
Ive been running a B230FX+T for the past 3 years and about 60K on LH2.2 with a 15g @ 10 - 12psi depending on how hard I press the throttle. This goes through an M46 that had 300k on it when it went in and ive put another 120k with about 60 of those being with the +T. Theres good advice here in this thread with the main one being, know the limitations of the setup and dont go driving it like a gorilla with flat shifts such. I'm still on the same clutch we put in it 3 years ago and its only just started to slip now. I dont baby it and it sees redline atleast once a day but I make sure its in the next gear properly before letting the clutch out and getting back on the power. I also used the pan method and had a half inch pipe bent and tig welded from the inside of the pan. It works but when I go to an EMS in the summer and pull the motor I will be drilling the block and threading a threaded fitting on it so I can connect a steel braided drain line for a more clean install.
 
B230F+T, aw70 MVP stall, 15+psi s256 turbo and its still going. Drove the car to California from New Mexico back to New Mexico loaded and numerous tips from NM to AZ.
I did have a huge cooler up front. What kills the transmission is flooring it in OD.
IV also done a hand full of highway pulls at 30+psi as well.
 
AW70's run lower line pressures and have smaller components (esp OD) than an AW71. they are categorically weaker transmissions.
 
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