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Dyno day predictions

VB242

I.M. Weasel
Joined
Sep 21, 2011
Location
Driving the No Malarkey Bus
I have 3 pulls today for $50 through the sports car club anyone want to guess what it'll do?
Stats:
B21- 2117ccs 8.5-1 compression ratio
China bay 20G with 2.5"-3" v band adapter welded on, turbo housing ported to smooth flow into transition
eBay 25x4x8 intercooler
90+ manifold
3" side exit exhaust with 11" glass pack
T5 trans, I assume the pull will be in 4th
26.5” diameter tires
3.91 1030 axle
24 psi on the MBC
5-8 degrees of advance at full boost
Stock k-jet fuel system
IPD turbo cam runs out of steam around 65-6600 rpms rev limiter set to 7k
Microsquirt with Siemens 788cc injectors
B21F intake manifold
I'm hoping near 300 hps but we will see
 
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So yeah that timing biz is pretty important, first pull made 157hp. I doubled the timing values at the top of the table and got 239hp and 244ft.lbs., needless to say I thought I'd get a little more out of her but happy to get almost a 100hp for $50.00. I need to make some detcans and see what I can wring out of it.
 
So yeah that timing biz is pretty important, first pull made 157hp. I doubled the timing values at the top of the table and got 239hp and 244ft.lbs., needless to say I thought I'd get a little more out of her but happy to get almost a 100hp for $50.00. I need to make some detcans and see what I can wring out of it.

I don't know the wheel sizes in your turbo, but apart from the compression ratio I don't see all that much difference from my previous setup (7.5:1 b21) which made 352whp and 344ft.lbs. at 30ish psi. 19.25 degrees at full boost. So I bet you still have a good bit of power left in that thing
 
I have 3 pulls today for $50 through the sports car club anyone want to guess what it'll do?
Stats:
B21- 2117ccs 8.5-1 compression ratio
China bay 20G with 2.5"-3" v band adapter welded on, turbo housing ported to smooth flow into transition
eBay 25x4x8 intercooler
90+ manifold
3" side exit exhaust with 11" glass pack
T5 trans, I assume the pull will be in 4th
26.5? diameter tires
3.91 1030 axle
24 psi on the MBC
5-8 degrees of advance at full boost
Stock k-jet fuel system
IPD turbo cam runs out of steam around 65-6600 rpms rev limiter set to 7k
Microsquirt with Siemens 788cc injectors
B21F intake manifold
I'm hoping near 300 hps but we will see

Would you like to post your ignition map?
 
Keep at it dude. I understand the desire to not blow the motor up. I definitely got bolder once I had a knock sensor on the megasquirt board to listen in for me. Before I always just had a friend drive the car on a flat deserted stretch of road while I listened in on detcans. We'd make pass after pass and incrementally bump the timing until I heard some pinging. That should get you closer to where you want to be power-wise. 24psi through an 8v should get you into the high 200's for power with a b21 with stock heads. If you can afford more dyno time with the det cans, that would be even better.

If dyno is out of the question, the next best thing is the dragstrip. As you add timing, if the trap speed increases, you know you're making more power.
 
it is very difficult for the newly initiated to dial in a timing map without the aid of a dyno. On a purely initeria dyno, it is also easy to go "past" what is best without getting knock on the dyno, and then discover that it's knocking it's brains out on the street. A set of det cans isn't a bad idea but even then one should be careful whilst driving around tuning.
 
yeah that timing map is a bit of a mess. ve table is a bit curious too.. looks fat in the 2-3100 range, and then drops off hard above 4000 (out of boost), what's up with that?
 
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