Yes! the highest when the engine is not running is 86kPa! Funny that that map is conservative because its for a dual 40mm 20v
Yes! the highest when the engine is not running is 86kPa! Funny that that map is conservative because its for a dual 40mm 20v
That's a VW, with a serious slant to the engine.
The A20 head has a pretty lazy combustion chamber so it needs to start combustion earlier than more modern heads. I sent you a new table to try out. You can also use a little more timing since you're at higher altitude.
C|
Loaded up the table and increased my rev limiter to 6k it is definitely feeling loads better. I think i need to experiment with the Air Correctors to try and lean out my mixture up top. Right now i'm not pinging from what i can tell, but my a/f is between 10.7-11.5 about 5k at WOT
Right ok so similar setup to mine, go with the 190 air correctors and see how they go maybe 145 mains jets for now.
Will try and get my idle jets out tomorrow night to see what size they are I know my pump jets are 50 as they came with 45's which are sitting as spares.
Mine are modded with 42mm chokes but 40mm is fine.
As for the rev limiter should be able to run the engine to 8-8.5k rpm with the cam you have especially with the lighter pistons although not sure how much heavier your new rods are compared to the old ones, the old ones are very light and strong I still use them only had one failure and that wasn't due to the revs or power output but the rod bolts coming undone from stock torque settings.
30miles isn't enough takes a good few hundred miles for the rings to seat really nicely I tend to notice a really good pickup in power and driveability when this happens!
Also yes slacken the tappets off they will need adjusting now that you've run the engine for a bit and will effect readings if too tight. Header won't effect compression reading.
Do another compression reading after some more miles and after you adjust the tappets, make sure that throttle is WOT when doing it and all plugs are out the engine.
Pump jets are 50 as i thought and for mains I'm running 155 and 170 airs on F16 tubes which yes is probably on the rich side but given the revs it uses and the bigger power it's probably not that bad.
the idle jets are 50 F6 and when tested for emissions it's so low it doesn't read on their machine so it should be tax exempt! lol!
Whats the fuel pressure set at? mines about 4.5 psi.
My fuel pressure is set at 3psi, so I could probably bump it up. I'm going to drop in some 145 mains with my 190ac. I put the 190s in yesterday and noticed my afr went from 11.5 to 13.0:1. So a small improvement. Still haven't opened it up past 6k. But I've had it pull to 110 no problem. Oh yeah and I blew a damn hose cap off.
Yeah you need to make sure everything is on tight and also are you running the Tstat? if not loose it when the engine revs higher than 7k all the time it will just bend the hell out of it and try and suck it through the housing better to not bother and have more power with cooler engine.
I finally got the carbs synced all together, i forgot about the little air metering valve on the side of the carby, once i adjusted that one on the low flow one, i've got a consistent 5kg/h at 900rpm across the board! Fwew!!! Car is feeling great and sounding smoother and smoother! In fact, whilst putting groceries in my car, i started it up, to just enjoy it, and it sounded so smooth, outside of the big cam sound, which definitely sounds great! Once, i get this thing at 1500 mile mark, i'll change to oil, and open up the rev limit to 7.5k! There is a dyno day in mid-late aug, so hopefully i'll be able to go to that, and then give everyone an idea what Hp this thing is making!
Should be interesting to see how it's power band goes can't see why it shouldn't have power all the way upto 8k with the cam and exhaust your running. Just a shame you left the head stock!! grrrrr!! lol!
Turbos out flow na heads for the cost
Not if you can do it yourself! lol! Just imagine a nice small blower with a nicely done head you'll have best of both worlds then!!
Hows it running now done anymore miles on it yet? I normally just take mine for a nice cruise up and down a nice long stretch of motorway steady 2500-3000rpm for hour or so once i've plugged all the leaks and made sure nothing pops off the coolant system!
Classic mistake i make is allways forgetting to tighten the bleed bolt so get about 10 miles down the road to find it's fallen out and all my coolants gone AWOL as well! lol! I allways keep a spare in the car with a 5 litre bottle of coolant now! and a few spare Jubilee clips too! doh!!
Dyno day is august 20th
Hey Guys, figured i'd give everyone the heads up on the Prelude...
It's running pretty damn good, but i'm starting to wonder if my pump is flowing enough fuel... Last night i went running up the mountains here in CO, and cruising in 3rd between 4.5k-5k i'd notice that i was running rich under throttle (12.5:1 afr) but all of a sudden my car would just run out of top end busting up the mts, and i'd look at my UEGO, and i'd drop lean all of a sudden. I'd shift to 4th and baby it, and i'd come back down...
I uped my pressure today, but my gauge is busted so i'm not sure what the pressure is, but i drove it around today, and everything seemed fine, but i didn't run it long... I'm wondering if this is why i was thinking in the 4th and 5th gear pulls that i was going to need bigger jets past 6k...
Ok, now for some video... Still alot left in this thing, if i can just get this tuning 100%
First the in car...
http://youtu.be/BbKJNZWGMcc
and next the under the hood!!!
http://youtu.be/X_MP6Y6vp9Y
on this vid, here are the high light times if you don't want to watch the whole 5 mins.
-start up... ~30secs
-getting on the interstate... ~1.28mins
-then another 3rd gear pull...~1.48mins
-right turn then 1,2gear and part of 3rd...~4.00mins
enjoy
You coming out tonight??? Let's see what efi vs carbs does
I watched the underhood first and must admit, the moment you started it, I got a little smile.
I'm glad you like! Still wishin I had a high def camera
Sounds like you got it running pretty well so far probably still a little tweeking to be done yet with fueling and ignition but balance sounds good idling better than mine but my manifold is level so it's nigh on impossible for me to get it right untill i take it off and have it machined flat.
Looks like it's pulling well from low down to top end no hesitation's anywhere, as for the fuel pump could well be not quite enough pressure or flow you need to get a pressure gauge really to get it right on a high tuned engine should have it at between 4-4.5psi, also could be maybe the float valves aren't a large enough size to flow the fuel in if the pump is big enough and you have enough pressure. I'll try and figure out what mine are I've stuck some slightly bigger ones in mine so will try and find the old ones whereever they are in my jet collection box but haven't seen that kicking around for yonks! got so much shit you won't believe it! lol!
Howmany miles you done now then? I really need to get on with changing my oil pan and getting that OBX exhaust header and 2.5" system sorted out then think about whether I should bosh on that A18 head or not, ultimately i don't think it will flow as well as the A20 but the jump in CR ratio could make it worth it overall especially for torque across the board. Let me know when you start doing some full power runs and see where your true powerband finishes and that will help me decide. You still running on std pump gas or with an additive or high octane fuel plus additive?
So i'm running a 2.00 needle valve going into the float, but i'm also running one of those specter autozone fuel pressure regulators... you think that cheap regulator is cutting down my flow enough that i can't get enough fuel into the carbies?
Also i'm thinking about these parts to buy...
55f9 idles...
50 pump jets
install my soldered bypass
maybe the 2.50 needle valves...
Right now sitting at idle my afr reads 10.5:1-11:1... So i'm thinking this is way to rich... but my 50f9s just aren't big enough, just cant get it to idle without turning the screws WAY out.
I turned my fuel pump regulator all the way up to max pressure!! that is helping for sure on my long pulls, its not dropping out lean anymore.
Last night i swapped my 145 mains down to 140 mains, and the car feels lots better, but still pretty rich... Anyone have any idea how much Advance i can run on 91 octane? 93?
the car feels a little bit more fluffy and zippy that with the 140s in. I also swapped my 190 air correctors out for some 200, can't really tell if that helped at all up top, but the car is def running a bit better. Right now i've got a just a scosh over 1200 miles! I'm going to be changing the oil friday night and do some tuning on the 8k side of things. Maybe add some more timing...
Last edited by hondalude86; 08-20-2011 at 10:21 AM.
here is two new videos for your viewing pleasure...
0-100
http://youtu.be/kUt8GF_itrk
20-90
http://youtu.be/cCrnaOmwTPI
did this video as a kinda comparison vid... i loosely timed it going 20-80 about 2 secs faster than my previous vid...
I'm took out the f16 emulstion tubes because the car just wasn't pulling to 8k. Put my super rich, f7s (the richest available) and the car was literally different animal
didn't start running out of fuel till i got to about 7300 rpm in 3rd. it pulls so hard and clean in 1 and 2 and most the way through 3rd... I tried to get this thing 130 last night, and what i did was push 5th to 90mph then dropped to 4th, was lean by 110... fuck this regulator!
get that fuel issue fixed!!! Mine is starting to run better. gotta play with timing a bit tonight. You coming out??
no dyno day btw guys, the dyno turned out to be a bust, and being strapped on cash, the likely hood of me spending 60-100 bucks for no tuning time just isn't worth it to me. Hopefully the vids have helped a little bit, but damn my gearing is tall. Right now i'm running these jets...
140mains
170 ac
F7 emulsion tubes
60f8 idles
45 accel pump
2.00mm needle valve
40mm chokes
Worked on my mates ZC powered CRX with some 40DCOE webers. Got them all synced up for him, but the poor bastard is running 32mm chokes in that little diddy. i told him to buy some 36s and told him that that poor car wont make it 9k with the 32s, and hell probably will be struggling with 8k... funny thing is this... His jet settings...
140 mains
190 Air correctors
F16 emulsion tubes
60f8 idles
45 pumps, no discharge
32mm chokes
2.00mm needle valves
like damn near the same setup jet wise...
sounds good, but i'm not digging his ignition setup, and the irony of it is, jared talked me into the megajolt and i was totally going to run the Electomotive setup... fwew, was that close! The Xsi is very limited, his setup as only 3 tuning points... idle/startup 3k rpm and 8k rpm. And the most advance he can run is 35 degrees. I'm running 44 at WOT at 6k+ without pinging, although, probably could pull a little out past 7500
It's possible to get the old chokes bored out to much bigger nearly 39mm i think funky managed on his 40's makes huge difference ZC will be severly choked on 32mm! Mine was on just 36mm!!
Still not convinced by the F7 emulsion tubes though but seems to be working on yours maybe it's the higher compression and lower cc not sure maybe worth a try but i have the next set of tubes that are richer and they car has never liked them and had to revert back to F16 maybe because your exhaust setup is much better I really need to sort that out will try and order OBX header and get new system made up in next couple of weeks.
Hmmm think you might be onto something here F16's come with 45's std, but a lot of people end up going for richer ones, I think somewhere somehow I managed to think that F9's were richer but in fact due to Italian logic they are leaner even though F8 and F7 are richer, so this possibly could bring me some large benefits on top end due to larger valves with more air would need a much richer mixture to gain more power and top end zippiness!
May have to give the F7's a go as well and see how it performs over the F16's
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