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Well I dropped the values 15 uS and it helped alot. Now instead of being 10.2.... which is as low as my afr guage goes, durring wot, it's now 11.0-11.2. I can live with that. No sence in washing down the cylinders like that during the transitions from part throttle to wot.
But then I think was I suppose to take the value down or up? Taking it down helped... head scratch.
I assumed that a lower value would shorten the added fuel delivery. Am I wrong? If I am can some one explain please?
AE is asynchronous to the main fuel delivery. The AE pulses will actually show up between the regular fuel delivery, so think about the AE fuel as being it's own pulse width, sorta...
Well the car did good at the track. Best pass of a 12.26@114mph. 1.91 60 foot. Launching at 2400. But here is a problem I've noticed lately. It makes alot less power up top then it use to. Rpms don't want to go up very much. As of now I'm shifting a 5600 to make those low 12 second passes.
It's very noticable.
First thing I think is either my valves are banging shut then open..valve float. Or the cam is warn out badly. I really noticed it after the head gasket went.
So does anyone know off hand some comp springs that will drop in, behive style, and what spring lbs shut and open should I look for. My installed hight I believe is 1.7 inches.
Also I'm looking to do the cam at the same time. Is a delta 272 a good cam or should I ask for certain dur.? After I find the springs and see what lift I can have I'll make the choice on the cam.
I plan on replacing this stuff in 2 weeks if possible.
These were some of the springs I was looking at. I could safely get .550 of lift out of them I believe. Should I be looking at stronger springs then this? Again my installed hight is 1.7 inches.
Laugh but iirc my springs are stock shimmer a little for more seat pressure. I got the heads from 34blazer. So he probly knows them better then me.
Well talked to delta for a bit. He laughed when i told him what ive put that cam though. Said it stops making power arround 4800rpm. The band is in the 2500-4800 area on the 260 cam.
So he recommended a custom 270 cam. It would have lift of .470 max with 1.5 rockers. I have 1.6 rockers so the lift would be arround .500 Ill have to post the cam card when it comes as he rattled off some numbers i forgot. But said it would help the turbo set up out and also make power up to 6000 rpm. I took his word for it that it will help me out but still keep it stable to drive arround the roads. The durration was something like 224/228 iirc @.050
For 120 bucks out the door i can go wrong for the lifter and cam set.
Im getting the comp cam springs 26986. He said use something that had about 115lbs seat pressure and it will be good to 6500rpm. Also in the area of 230-240lbs per inch rate. So those springs fit to what he says is good. Preload of .040 of course on the lifters which is what i ordered the pushrods for anyways back when i did the hybrid swap.
The bind hight is nice also. Plenty of room in there for a cam with that sort of lift. After the 1.7 installed height, the 1.06 bind height, and .060 for a grace area i still get around .580 for safe lift area.
Hopefully this will help my top end power issue as the car makes mass tq down low but higher rpms its just not getting it like it should.
One thing i think is that when i blew that head gasket i may have messed up the lobes on the cam from bad oil contained with water. Just a thought. But then again the springs are stock so what can i really expect from them.
Hopefully its all here and i can toss it all in and break in that cam in 2 weeks.
Yea good point but first things first i need to get the cam and springs and see if that helps me out up top. Hopefully it does. Dave you ran a 272 didnt ya? On a dyno run also.....when did the hp fall off drastically? Do you remember your cam card? Was it close to those i listed down there for a 270 grind? Keep in mind i have 1.6 rocker ratios on the lift total.
I know the old cam car specs are right and the new ones should be close as this is what i wrote down on the phone when i was talking to delta cams. I have a 3500 stall converter so im really hoping this little addition helps out the car a bit and squeaks out a little more power. Ive had that lil 260 cam in the car for 4 years now. I remember back as that was the first time i attempted to ever tear into the old camaro and do any performance mods. Ill have to frame that lil cam....
The old cam was this
Lobe sep 111.8
Duration at .050 intake-209
exhaust-212
Lift with 1.6 rockers intake-.457"
exhaust-.465"
New delta 270 cam
Lobe sep 110.2
Durrration @.050 intake-224
exhaust-226
Lift with 1.6 Rockers intake-.501"
exhaust-.509"
Yea good point but first things first i need to get the cam and springs and see if that helps me out up top. Hopefully it does. Dave you ran a 272 didnt ya? On a dyno run also.....when did the hp fall off drastically? Do you remember your cam card? Was it close to those i listed down there for a 270 grind? Keep in mind i have 1.6 rocker ratios on the lift total.
I know the old cam car specs are right and the new ones should be close as this is what i wrote down on the phone when i was talking to delta cams. I have a 3500 stall converter so im really hoping this little addition helps out the car a bit and squeaks out a little more power. Ive had that lil 260 cam in the car for 4 years now. I remember back as that was the first time i attempted to ever tear into the old camaro and do any performance mods. Ill have to frame that lil cam....
The old cam was this
Lobe sep 111.8
Duration at .050 intake-209
exhaust-212
Lift with 1.6 rockers intake-.457"
exhaust-.465"
New delta 270 cam
Lobe sep 110.2
Durrration @.050 intake-224
exhaust-226
Lift with 1.6 Rockers intake-.501"
exhaust-.509"
its been so long but i ran a custom grind after the 260 it was right around the specs of that 270 just more lift , with a turbo that 260 cam will rev high with the right valve springs , im wondering if u havent wiped out the valve springs on ur motor and the cam is just fine. that being said the 260 cam is suited more twards the iron heads the the aluminum ones
Definitly possible dave. I got the new comp cam valves today in the mail. Their open is 284# and closed is 126#. I think thats plenty of spring. What sold me was the bind hight of 1.06. That gives alot of room for lift. I dont like cutting it close. I know my current set up is about .0xx from binding. Thats no good.
I just hope i can get it all done in a day. Changing springs with the head on is always fun. Time to pump up those cylinders and get at it, next saturday.
Made a few passes today. Did ok. I lost in 1st round. Car picked up a ton 12.06 and I literly was peddling it for awhile so I probly had a 12.01 or 12.0 on that pass. Still about 15psi. Here's a few slips. Nitrous pressure is my thinking on the erratic 60 foots. Amazing what a little bit will do.
Tossing in the cam and springs. this week so hopefully that helps. I was shifting at a solid 5500 all day today on those slips.
Yesterday it was a 12 flat car and now i went and tore it apart...
I had 2 hrs today so what did i do. So I took out that old cam. Took about 1 hr 45 minuets. Dang i tear this thing apart too much. Anyways. Is this normal wear on a cam? And the lifters? The cam bearings look great but then again there only about 5k miles old. Thanks for any input.
Also what is the deal with timing chains. Its not sloppy loose but does have more slack then it did out of the box. Is that normal after about 5k miles of beating. Nothing like the original i took out before but i was just wondering if its going to stretch a bit compared to right outta the box. Thanks again.
Ill be putting in the cam and new springs this saturday hopefully.
lifters nearly look like they were spinning in the bore or did some, cam I can't say, maybe cause of the up close pic, but ive seen cams in many engines big and small, I dunno is it smooth, what with the spots, is that micro texture?
Well i tossed the cam, lifters, dizzy block off, and timing chain stuff in really fast today. Lots of assembly lube. But ill get at the car on saturday. Im checkin pushrod length because IIRC when they regrind the cam its literly making the lifters sit lower now. So if that becomes a issue ill have to figure something out. I already checked the exhaust and there good to go. about .035 preload. But just off of of tqing down the intake side they look weak. So im either going to have to get new rods on the intake side or possibly shave down the pedistals on the rocker or on the head... ill probly only need .020 or .025 at most. Ideas?
Edit. I got new rods for the intake coming. After measuring I only have .010 of preload.
Dave thats too far away for me or id be there for sure.
Well i tossed the cam, lifters, dizzy block off, and timing chain stuff in really fast today. Lots of assembly lube. But ill get at the car on saturday. Im checkin pushrod length because IIRC when they regrind the cam its literly making the lifters sit lower now. So if that becomes a issue ill have to figure something out. I already checked the exhaust and there good to go. about .035 preload. But just off of of tqing down the intake side they look weak. So im either going to have to get new rods on the intake side or possibly shave down the pedistals on the rocker or on the head... ill probly only need .020 or .025 at most. Ideas?
Edit. I got new rods for the intake coming. After measuring I only have .010 of preload.
Dave thats too far away for me or id be there for sure.
was worth a shot , i figured it would be way to far lol
just fyi in the Buick world you can get adjustable push rods any size/range you wish. Lots of of use em on the high end motors. Guy I goy my Stage 1 BBB 430 from uses them in his race built 455 [ Im still using the factory no adjustment needed, just torque down rocker shafts, adjustment is done - i hate adjusting valves, I hate hard to reach hidden oil filters, I hate reaching over motor to adjust the dizzy, I like external oil pumps you can service at will. Yep I love Buicks...]
No body uses "adjustable pushrods" (in a running engine). Those are test/check pushrods, to ensure the proper length is ordered.
Also, .020 pre-load may work for some, but .040 is not too much, in fact it's recommended pre-load for the GM 60 degree V6, and if that's what the lifter manufacturer recommends, that's what should be used.
Last edited by Six_Shooter; 07-14-2015 at 11:12 PM.
"TA adjustable pushrods are ideal for many performance combinations. They provide an inexpensive way to incorporate an adjustable valve train when needed. "
Oh and since they are all custom made, you should have no trouble calling up TA, talk to Mike n he could get you any range you wanted, if they don't have it already.
[ Why is this popular with only Buick guys, as mentioned, many Buicks have non adjustable valve trains. Some folks want that fine tuning without major changes and cash. IM happy to not have to deal with it, just bolt on rocker shafts n your done. ]
Stock spring on the right and new 26986 on the left.
Also noticed that the seat of the spring is bigger and not completely snug on the seat. But from all ive read that is the spring that works fine and is a drop in replacement. Anyone use these springs and notice that?
Ive got 2 cylinders done so far. Im doing it the old, pump up the cylinder and replace them while the heads are on, deal.
It may be me... but damm it's faster. Alot faster pulls hard till you decide it's enough. I added a ton of fueling and I'm officially at the max on these injectors. I added a average of 8% to most of the boosted ve cells. My injector dc is from 82% up to 89%, that 89 is at the 6k rpm area. Use to be mid 70s no matter the rpm. 15.75 psi command boost.
Damm car had me shaking man...lmao I made 2 pulls. Had to let it cool down between them. It's hoot and humid here again today. Intake temps started at 90 and ended at 114 at end of pull.
Here's a vid of the idle and a 2nd to 3rd gear pull. If this thing can make a good clean start. 1.85 60 foot or so I know the trap speed will be better then 115. My hopes... 120 give or take if I'm lucky...
Damm cars ready for the weekend. No more pulls on the road, im too old for that crap. I hate doing that but i wanted to make sure the tune was dead on and it is. But i had to pull out .5psi of boost so im back to 15psi again. I had to do that to keep the afrs in check and keep the injector duty cycle at 83-85% Which its pretty much steady at those numbers.
Update. Ran a best of 11.85@118mph yesterday. It was freaking hot out. I'm pretty happy with the mph. That's on 14.5 psi of boost. And the 60 foots sux. 1.87 was on that pass. May be time to step up the n20 off the line a bit. I'll post vids after work.
very nice some more nitrous should do the trick , though if u leave it as such a small shot u could run it down the track a bit . honestly i would do a diy 8.8 rear end and get a trans brake
This race below is with a friend in his mustang. It dynoed 393 rwhp last week when he did some work to it and had a shop dyno tune it. Nice to get out in front and pull away.
Yes I hope with a little bit of nitrous it will be a little faster off the line. Right now I'm basically limited on how fast it is on the top and because of the fuel injectors which are maxed out. New ones cost a pretty penny so I'm going to just enjoy the car the rest of the year and work on my starting line launch. I won't race for two more weeks but when I will out up the n20 with 25 horsepower and see what it does. I still think 118mph for a trap speed is amazing with this car I never thought it would go that fast in under 12 seconds.
A good 60 foot should bring 11.50-60 easy in cooler weather i would think
Dave you have no idea how bad I'd love to have a trans brake and bump box in this car. .......
..... I could post the patch/XDF I made, I don't know if I ever released it publicly or not. I think only 1 or 2 people have asked about it in the past year, so it didn't seem like much of a priority. it's using more or less the same code I worked out with nAst1, which had great results.
if you were to cut power to it, yes. the way my patch works is that it keeps the Bypass circuit active and just quits sending EST pulses to the ICM, so the ICM just quits firing coils. it should still be monitoring the crank/cam sensors and sending pulses to the ECM at the correct time.
$58 and $59 don't monitor cam position, so it really won't matter. The ICM in a DIS setup syncs to the crank position which it's a signal that will never be influenced by the ECM since it's completely separate.
$58 and $59 don't monitor cam position, so it really won't matter. The ICM in a DIS setup syncs to the crank position which it's a signal that will never be influenced by the ECM since it's completely separate.
I asked about a strategy for the buick ignition, since the ICM is different. Sorry for the distraction.
Saar, is there anyway you can e-mail that to me? Then I can put it on gearhead. I don't particularly want to create a dropbox account just to download one file.
Saar, is there anyway you can e-mail that to me? Then I can put it on gearhead. I don't particularly want to create a dropbox account just to download one file.
did dropbox change their policy on downloads? i just opened a private tab and wasn't logged in and it allowed me to download it without signing in. just closed out of the registration box and clicked download.
in any case, i would mention it being beta until further notice.
07-04-2015, 09:12 AM
- i hate adjusting valves, I hate hard to reach hidden oil filters, I hate reaching over motor to adjust the dizzy, I like external oil pumps you can service at will. Yep I love Buicks...] 
