SD2 tuning

[reality]

I didn't mean to single anyone out I just meant turbo
 buick people in general. Sorry.


And for the canadian guys the converter in LC's car was a vic Richards from Mississauga ON. yes that Sippery Vic.

[good2win22]

Sorry this thread got side tracked to a valve train topic but I wasn't exactly sure what the problem was or is.


Anyway, spent the day measuring spring pressures, taking a lot of precision measurements and then doing a bunch of math.  After that was all calculated, then spent some time in the TA paper catalog as well as on the jegs and summit sites.


Taking all valve train theories into consideration, i.e. spring pressures for roller cam, spring pressures for forced induction engines, spring height settings meaning getting within .100" from coil bind or as close to that and still have adequate spring pressure over the nose and adequate spring pressure on the seat, insuring that the retainer doesn't hit the valve stem seal, making my own assessment of what is a good median for drivability vs racing... I think I got it figured out.  Only one thing left to get and I won't be able to do that till I get it all back together and measure for pushrod length.


I'm not gonna throw out any numbers till it's all back together and tested. Probably will be another few weeks before that happens as I'm working 12 of the next 14 days.

[good2win22]

Everything is back together and running as advertised.  Spent yesterday tying up loose ends and breaking in the new lifters, springs, pushrods, getting the coolant level set and then changing the oil and filter.  Note to self, when tying up loose ends check the oil pan drain plug just one more time. 

Weather was holding off this morning so I decided to clean the old girl up before getting it on the road for a test to see if it was going to rev past 5200rpm.  I am completely thankful for all the folks that took the time to talk with me and educate me with this issue as it paid off.  I got out of the throttle around 5600 as a cop car came over the hill on my test road.  There was a bit of KR so still need to tune but overall I am pleased. 


I may start another thread to lay down the numbers of my set up if anyone is interested.

log attached 

[Scoobum]

AF looks erratic...whic h may explain the slight KR. Boost is only 16...so if you have the alky on...that could be making the engine 'hunt' a little. Got a call from Dan one time. A customers cars engine was 'hunting'. Boost was only 15. Had Dan bump it to 20...and it cleared up. Figured the alky was drowning it at only 15.

[good2win22]

AF looks erratic...whic h may explain the slight KR. Boost is only 16...so if you have the alky on...that could be making the engine 'hunt' a little. Got a call from Dan one time. A customers cars engine was 'hunting'. Boost was only 15. Had Dan bump it to 20...and it cleared up. Figured the alky was drowning it at only 15.

That's a thought to consider. According to Eric, he says the SD2 will maintain +- .3 on the WB and it does stay within that parameter but it does move around a little more than I would like.


Going to reinstall the HD actuator, turn it up a bit and see what happens now that I can get the rpm's that I was shooting for

[good2win22]

Changed out the stock actuator to an adjustable HD one and went for another high gear run.  Started at 17 psi and creeped up to 19 at 5600 rpm. Just a touch of KR going up to 5000 but then dropped to 0. 

To be honest, the car scares me a little. I guess it's gonna take some getting used to going that quick

Log attached

[Scoobum]

Jason...what's the low/high timing set at?

[Scoobum]

Looking at the file it might be something it's hearing at a shift point in regard to KR. If you can...take off from a dead stop...so we can see the shift points...and if the KR occurs at one of those points.

[TexasT]

I told you it would be a real serious street car once you got it together. Just that much cooler with the chrome trim.

[good2win22]

Jason...what's the low/high timing set at?

High gear is at 19. Low gear... I haven't looked to see what it's at.  I have a feeling the passenger side header is touching the upper control arm. It's pretty tight in there.

Looking at the file it might be something it's hearing at a shift point in regard to KR. If you can...take off from a dead stop...so we can see the shift points...and if the KR occurs at one of those points.

I don't have a tire that can hold it from a stop unless I put on the slicks. Not gonna do that on the street. I just need to get to the track.

I told you it would be a real serious street car once you got it together. Just that much cooler with the chrome trim.

Thanks Rich.  Need to dial it in

[TexasT]

Dialing in is way easier than bolting it together. And way more fun too.

[gusszgs]

Good for you on getting it sorted 

[TexasT]

These logs are just straight gas? How old is the gas? The knock is way down in the 3k rpm range. Not sure what it is but you only have 19* of timing there. maybe back it off half a degree or a degree and see but I think it is just picking something else up.


Its gonna be a deathtrap with alky and 30psi.

[good2win22]

These logs are just straight gas? How old is the gas? The knock is way down in the 3k rpm range. Not sure what it is but you only have 19* of timing there. maybe back it off half a degree or a degree and see but I think it is just picking something else up.


Its gonna be a deathtrap with alky and 30psi.

That's with alky. Gas isn't that old. I had just put some in the tank before tearing the engine down.  Maybe 3 months old. I will play with the tune some more when I get off work.


Don't think I'll have the balls to put 30 lbs to it.

[TexasT]

Three months is winter gas and I would say it could use fresh. I know I picked up 3 or so mpg in the last two tanks as I guess they switch the formula as the weather warms up.