Jay I'm running the Barry grant 650 blow through. I stepped up the secondary jets 4 sizes I think it was. There was still some more tuning to do with it though. It was running good but a little boggy and rich, I reckon on a dyno these carbs could really get dialed in with a good tuner and a tuning pack. Have a read up on the emultion and air bleeds if you are game for the fuel curve. I havent messed with these yet. This Is where Id like to use the dyno tuning, and peek over his shoulder.
Talking of carbs I've just rememberd somthing else that may be of use that I completly forgotten about. When I was cruising and hit a lean spot and started pinging I popped the hood and started looking around I shot the timing light, checked fuel pressure, checked all hoses etc. I discovered I had lost a needle. The carb was sucking air through it. Two days later I lost another one. I checked the other two neddles and those little o rings around the needles were brittle and not sealing to good. I got some replacemnts and wasn't happy with them either. I bought some Holly corks and used them. They seem to seal and hold the needle much better then the Barry grant rubbers. I wouldn't use those Barry Grant O ring rubbers again. Not unless I put four pieces of tape over each needle so they can't fall out of the carb. No doubt this was causing additional air in the fuel mix. I could hear the air sucking straight through the needle holes.
I'm not real happy with my carb. I have the WOT afrs where I want and the cruise where I want but the mid throttle is lean. It's VERY likely that you won't find anyone that knows enough to change air bleeds.. We are on our own there. I've made some changes, just need to get the snow to go away and test drive it..
Since he mentioned the Holley corks I'd assume he was referring to the idle mixture screws. Not the idle air bleeds
No.. I'm pretty sure he was referring to changing the high speed air bleeds, which affect the AFRs in the same way changing out main jets would.. All kinds of tuning can be done with the air bleeds..
Oh yeah, I'm back in Australia again. Sorry about the confusion I mean't idle mixture screws. Heres a pic. I took her out for a spin, She started up first time even after sitting for a month but back fires and pops real bad, quite a bit of dark smoke out the exhausts, Weird thing is the AFRs on the gauge go from 2 to 36 when letting off the throttle but seem to average around 12 to 14 at ecceleration. Still exhaust smoke comming out the rocker covers but not much oil. No pinging noises, but theres proberbly not much left to ping on under them heads. I'll start looking into things over the next few days and will post pictures of the findings. Anyway I need to put some pic's up of the turbo's.
That's a real bummer Byron. My guess is, the tune went lean under boost, popping some ring lands. The resulting blowby prevented proper oil drainage, hence the turbo blowing oil past the seals. You shouldn't need to restrict a journal bearing turbo under .110" to stop flooding oil, unless there is another problem (like crankcase pressure). We'll see what really happened soon enough though.
Time to check in over here and learn even more.. Might find a buddy nearby.. http://www.theturboforums.com/smf/index.php?topic=62756.0
Well. The engine is toasted. Rings gone. Head gasket blown through on the intake side. I'm not going to bother messing with it any longer. I found a Father and Son Dyno engine building shop up the road from me who are friends with some Buick club guys. The Shop owner built a Twin turbo v6 Buick 15 years ago and got 1200hp out of it, he was also invoved in the Buick Indy stuff 20 years back in Australia. Says he's not afraid to build it right and thinks I should consider putting injection into it. Reckons the injection is way more accurate compared to blowthru for the fuel curve. So it looks like the engine will be down for many many months to come. In the mean time I've sourced an alternative powerplant and drivetrain that I can resell later on at close to what I will buy it for. Don't Nag on me but it's a GM 502 HO engine/TH400 trans. I need this car to run cause I'm paying $1500 a year to keep it regestered and insured might as well drive it with any engine. Needless to say I won't be posting on the progress of that swap over. I will post on the Buick Engine rebuild, and the eventual Dyno tune. Man where has all the money gone.
I look forward to hearing about your 350 build....:beer Regarding the 502, it sounds like a great way to stay on the road and have fun! Just use the chevelle BB mounts and frame pads, not too bad of a swap.
I don't even know what to say.. Wonder why it went so lean??? I've beat the snot out of my setup and every time I drive it home and park it in the garage and nothing leaks, I just can't believe it. Good luck with the next build.. I'll happily give you my number to call if you have a question I can answer.. Jay
Thanks Sean, This time I'm waiting saving and doing it 100% right with these Dyno engine builders. I've felt the awsome torque of the Buick 350 and I'm hooked. The 502 might be a good standby motor later, mabe sell it OR build a hotrod for the wife!
I really don't know, I thought mabe power valves not keeping up in the BG carb? Just so many things hapened all at once, or mabe it seemed that way. I've got the comp cam with your grind at home it looks mean and chunky. I just need to be patient.
I am doing a MPFI setup using megasquirt and there are a few others doing MPFI setups for turbos as well. Have a look at this setup that happens to be in AUS.... http://www.v8buick.com/showthread.php?t=193177&highlight=mpfi+ta+intake
Thanks Sean, looks interesting. I think I'll leave this to the experts. I already toasted my EFI Harley a few years ago. At that time No Dyno tuners in my area knew how to tune the H.D EFI screamin eagle pro super tuner so I tried my hand. It was great fun for 700 miles and a few pulls at the drags. What is it with me and engine upgrades? They always seem to fail the first time.
Good idea to leave it to the experts, however a TA intake setup for MPFI would give you a head start for the experts to add whatever system they like. :3gears:
Ah yes I see. The fuel rails on manifold look neat don't they. I just bought that 502 engine and transmission. I gotta say a total bargan still in the crate with a 600 hp built trans for $7500 bucks. these eninges sell in G.M performance shops in Australia for $10,000 looks like I've saved around $5000. The same Dyno engine builder for the buick engine will dyno this one for me. Can't wait for it to all start.
