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TA49 vs Precision 6262
- Thread starter Turbo Keith
- Start date
jasjamz
THS Racer
- Joined
- Sep 30, 2004
This is not good advice. I would not follow it. All cars have different likes and things that work for them. Their A/F ratio is rich for some as he said knocks when leaner. May want to look at what plug they have in. Fuel pressue and amount of alky going in as well. We dont have enough info to say the things you said. Not lower the boost. The Timing is average for that boost and Ive ran more. Some use less.
Turbo Keith
TURBO KEITH
- Joined
- Sep 16, 2015
I did what everyone said , Call Dusty , PTC is the way to go . Dusty said the 10 " LU is what he said will work for the 49 and will work if I go to a 6262
SpeedRacerX
Well-Known Member
- Joined
- Jan 20, 2014
Can I have another bucket of popcorn please? Lol.
Sent from my SAMSUNG-SM-G900A using Tapatalk
Sent from my SAMSUNG-SM-G900A using Tapatalk
On my 10 sec 49 combo with the stock cam i ran 2 m10s and 42lb injectors.30 psi with timing in the 26 degree range and even went higher.these are real results.still waiting on a response from you regarding your real world 60ft results.
Really you can say that regarding every mechanical piece in the car If it quits
I have seen more fuel pumps straight up quit and no alky pump failures they drop off pressure eventually and if your looking at a gauge you can see it.He said when he leans it down it knocks. See you're just looking at numbers and you're actually not paying attention to the testing that he is done,each car is different.
It's building heat as it's going down the track. Richening it up or adding more meth to cool it down is the only way to keep it together.
I love the 9.5 non lock ptc.working is different from maximizing. We tested a lot of different things to make the 49 combos run. On the lock up stuff we found that making the converter very loose and then doing a manual lock up was the fastest way.i mean real loose we were 3200 to 3500,but if you didn't lock it down it would lay over on the big end.locking it down was 5mph on a 49 and stock motor.looking at the slips you can see where things are soft or could be improved. What I'm talking about was done a very long time ago and I haven't ran any of the new converter teck on a stock combo would a 49. We were dealing with D5s orange stripes, red stripes ,Vig multi disk lock ups,a.c. 9 non lock, and pro torque made a killer 10.5 with a lock up clutch that could be used at wot.but in the end loose down low and coupling up top is the answer,the 49 when setup right hits real hard and has the ability to nail down the 1st half of the track real good mine would run high 6s in the 1/8 and fastest 1/4 mph was 125.
I had a 5831 on 28psi with the 10” ptc lockup, but when I went to the 6262 I changed to a 17 blade 9.5” ptc. I was making mid 500’s to the tire on 29psi and 17* timing on pump 93/meth with the 6262jb. Ported irons and the same Edelbrock 204/214 cam. I think the potential of the 6262 will overdrive the 10”, but it’ll work if you’re looking to stay in the 11’s was the consensus I came to. You’re leaving power on the table not going over to a 9.5” though with the 6262 turned up.
- Joined
- Aug 1, 2003
the 9.5 nL th400 converter from dusty that was used for low 9s on a gn1 headed 234cube 71hpqbb motor works better than expected on a stock engine-untouched heads stock cam -pistons -timing set and stock turbo ..so far 118.9 11.20 (1.51 60ft) all at under 4850rpm
Where were you locking the tcc on the 49? We tried a lot to gain mph out the back last season, but only could gain 20mph. I tore into the engine and realized the exhaust lobe on cylinder 3 had a whopping 0.135” lift. How taxing is it on the clutches to lock it up like that? We are at 22mph out the back last week going 89mph in the 1/8 and 111mph at the 1/4, unlocked tcc. I pulled a degree out up top and we are going to try and get it in the mid 10’s afr around 25psi this Friday.
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First was the top of second gear about to go into 3rd at 18psi. Afr dropped to 11.2 and then 10.8 toward the end of 3rd. That is what I wanted, but the car didn’t like it. *he spun on the launch. In the second graph we fed it more fuel and at the very end of the run was 21.1psi and 0.7kr. This Friday we are going to get the boost up to 22-26psi and get the afr in the 10.2-10.4 range with a degree of timing pulled and see what it’ll do. His car idles best in the 12.8-13.2 range, so I told him the sensor may be a little off from the actual afr.
Attachments
This is the turbo I have on my truck, all stock motor. Instaboost with a good converter.
Converter could be tightened up some for optimal 1/4 mile times as I was originally going to go with heads/cam. I had tried a couple other bigger turbos with the stock engine and they spooled like dog. This is a fun combo for stock setups.
I was locking in 3rd gear,tried it all over the place but it would et better with mid 3rd gear lock 25mph back half at 3732lbs on its worst day 23.i hammered mine on the street a lot got a lot of passes and good miles on it but the clutch was very worn I upgraded to Kevlar single but moved to a ptc 9.5 for a combo change.overall I think it's tough on the clutch but it works
We also had good results with the Pro Torque 10.5 lockup on mild combos with 49 and similar... could take a lot of WOT lockups. But as Paul mentions the nonlock PTC tightens up top even on stock combos... 23mph pickup on stock turbo/heads/cam. Will be interesting to see how a 49 would work on same combo.
Didn't see before. If it's knocking you always turn down the boost and check fuel trim and logs. Fuel trims first first. Fuel pressure 41-43 vac off at idle. Alky gain 5 /5.5 is a good start.
This isn't 1980 anymore . Most chip makers stay under 20* @ wot anymore, or no higher than 18* up top. Never had an issue. Hi timing equals High cylinder pressures
Mr Spool , never had a alky pump fail? One of the best turbo buick gurus just posted on this thread had a pump fail. Mine failed...
This isn't 1980 anymore . Most chip makers stay under 20* @ wot anymore, or no higher than 18* up top. Never had an issue. Hi timing equals High cylinder pressures
Mr Spool , never had a alky pump fail? One of the best turbo buick gurus just posted on this thread had a pump fail. Mine failed...
The closed loop feature of the sd2 doesn’t really act as it should, at least this one anyway. Sometimes if you want to target 10.8 via the afr table it will make you set it to 11.6-11.8 for the wide band to actually read a 10.8afr and 0.0% correction. This was on two cars and the sensor was replaced, so I deemed it was something in the software that had to be worked around. I used the spool mode feature to attempt to keep it in open loop during spool up (time delay and map threshold), but the same issue arises when I place it in closed loop and conditions are steady. I just tuned it in open loop and the fueling is more consistent, so there is no correction given back. The Alky is at 5.75-6.25 roughly. Cruise and occasionally idle I will have it in closed loop where I can adjust the VE or coolant/iat fuel compensation. The Fast unit I have on my car is dead on as far as targeting an afr and it keeping it within acceptable limits.
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