Author Topic: Fine tuning Q-jet  (Read 8251 times)

Offline Cliff Ruggles

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Re: Fine tuning Q-jet
« Reply #45 on: May 18, 2022, 01:49:02 PM »
The 200-4R's were also continuously evolving transmissions much like the 700/4L60 models.  The factory continued to make improvements to them thru the years of production which included hard parts upgrades/modifications and also valve body improvements.  For the most part the hard part upgrades were in place by 1986.  Not all valve bodies are the same, nor are the separator plates.  They even made mid-year model changes, so tread softly when you are rebuilding and/or upgrading your 200-4R transmission as you may run into differences between them not always noted in publicized literature on them.  ATSG has been the most accurate in that area if anyone gets into trouble there.

It's been a while since I did one here, but I do remember it was from a 1984 Hurst Olds and the one I was into had an anomaly with the separator plate/check balls used but I can't remember exactly what it was since it's been at least 4 years ago and I suffer from bad cases of CRS and even worse cases of DGS these days.

Anyhow, over the years I've been into a good many of them.  For the most part I made it a habit to upgrade all the "soft" spots even if it was a later model.  The hardened/upgraded parts aren't really that expensive, and if nothing else you'll sleep better at night knowing they are in there.  I also put aftermarket converters in them capable of handling a lot more power than the stock units, plus the triple disc option for the TCC if we were using lock-up.  Doing so allows the use of lock-up under full power as early as the 1-2 upshift.  This ceases all torque multiplication (the Buick 3.8 turbo engines love that deal) and puts all the power right to the pavement.

Overall they are pretty tough little units.  I've had near perfect success with them here, other than having a customer burn one up in short order as his TV cable somehow got WAY out of adjustment and he was out hammering on it pretty hard........

Offline 73ss

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Re: Fine tuning Q-jet
« Reply #46 on: May 18, 2022, 04:01:04 PM »
I'm running a CZF 200-R from an 86 Monte SS. Full throttle shifts are at 4900 RPM. Not a whole lot better than the Non SS trans. The 305 HO in the Monte was all done by 5K. I been running it for 10 years now behind a big block in a chevelle and it has held up quite well. I have broken one torque converter in the 10 years. A shop in the Akron Ohio area built it for me. It's the go to place for the Turbo Buick crowd. It's been a good unit.

Offline 77cruiser

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Re: Fine tuning Q-jet
« Reply #47 on: May 18, 2022, 04:24:22 PM »
My CQ vb, I got the full throttle shift to 6400, but the part throttle shifts follow somewhat & are kinda high at anything but light throttle.
Jim

Offline von

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Re: Fine tuning Q-jet
« Reply #48 on: May 19, 2022, 02:48:43 AM »
Mine is out of an '86 Monte Carlo, non-SS. I used the Trans Go shift kit and other upgraded parts like 10 vane pump, Buick GN valve (I forget the proper name), wide band, hardened sun shell, etc.,and drilled the separator plate holes out to the max recommended by Trans Go. The part throttle shifts are very firm, especially the 2-3 (almost bang shift). The WOT 1-2 shift (about 4400 rpm) is softer than it should be and I've scratched my head trying to correct that for years and finally just live with it since I don't go WOT that often. I used the ATSG manual as a guide when building the trans. Engine is a well tuned bone stock low compression 350 with Q jet. Converter is stock replacement 1800 rpm stall. Rear is 3.36 posi in a '69 Chevelle. It runs very well for what it is.

Offline bob69

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Re: Fine tuning Q-jet
« Reply #49 on: May 19, 2022, 09:50:56 AM »
Von, were you able to confirm the valve body was coded CRG? And did the valve body have pink paint on it. The pink paint identifies the valve body as the monte carlo HP vb. It was used on CZ and CR transmissions.

I've read that the "pink" CR VB can be can be easily upgraded to CZ SS specs. Like modifying the governor to increase rpm shift points. 

Offline bob69

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Re: Fine tuning Q-jet
« Reply #50 on: May 19, 2022, 10:40:11 AM »
The 200r4 discussions reminded me of the tests I did following the install (many years ago). I did a few tests with changing gears manually. At the time, the engine/trans would rev easily to 5000 in second and third. The engine was replaced when it developed low oil pressure problems.

The engine was replaced and same q-jet was used on both. The q-jet still had some of the same problems that were identified earlier in this post. Except this time I had no performance.  If I had remembered that the q-jet did perform in the past, I may have identified the problems with "new" fuel pump and gas tank sock sooner. Live and learn......

Offline Cliff Ruggles

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Re: Fine tuning Q-jet
« Reply #51 on: May 20, 2022, 03:16:28 AM »
Fuel delivery is a BIG deal when it comes to tuning.  I get all sorts of calls from folks wanting richer secondary metering rods because they are having high RPM issues with the engine going flat or loosing power.

Just had a customer in here a few days ago that had his carburetor "professionally" rebuilt/restored and it wasn't up to par for his big block Chevy 396 engine.  I removed the airhorn and low and behold it had a .110" N/S assembly in it.  That wouldn't keep up with a decent running 305 SBC let alone his "warmed over" 396! 

Last time I looked it was 2022 and I wonder why folks rebuilding/restoring these carburetors continue to install the WRONG parts in them then blame the carburetor for not being good enough or big enough for what they are doing?............Cliff

Offline von

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Re: Fine tuning Q-jet
« Reply #52 on: May 21, 2022, 07:16:54 AM »
Von, were you able to confirm the valve body was coded CRG? And did the valve body have pink paint on it. The pink paint identifies the valve body as the monte carlo HP vb. It was used on CZ and CR transmissions.

I've read that the "pink" CR VB can be can be easily upgraded to CZ SS specs. Like modifying the governor to increase rpm shift points.
I found some pics I took when I had the trans disassembled for rebuild. The VB had CR something on it but the third letter or number was hidden. I didn't see any pink paint. The trans is from an '86 Monte Carlo 305 NON SS.

Offline 77cruiser

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Re: Fine tuning Q-jet
« Reply #53 on: May 21, 2022, 07:42:19 PM »
Too bad you couldn't round up a CQ or CZ valve body. They have around 5000 to 5300 with a GN gov.
Jim

Offline bob69

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Re: Fine tuning Q-jet
« Reply #54 on: May 22, 2022, 08:19:38 AM »
Von, well that makes things more complicated. All of the posts I've read about the 1986 monte say the CR vb is made with the same basic core vb used in the CZ. The CR vb can be made to perform like the CZ with minor mods like changing shift springs, line pressure and the governor to the CZ piece. The govenor mods you made should have result in some rpm increases.

What's confusing is that performance vbs in 1986 monte were marked by GM with pink paint and you say yours was not. Now I wonder if the changes I planned to mine will be worth it. 

Offline von

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Re: Fine tuning Q-jet
« Reply #55 on: May 24, 2022, 05:11:33 AM »
Von, well that makes things more complicated. All of the posts I've read about the 1986 monte say the CR vb is made with the same basic core vb used in the CZ. The CR vb can be made to perform like the CZ with minor mods like changing shift springs, line pressure and the governor to the CZ piece. The govenor mods you made should have result in some rpm increases.

What's confusing is that performance vbs in 1986 monte were marked by GM with pink paint and you say yours was not. Now I wonder if the changes I planned to mine will be worth it.
Mine could have pink paint on the VB, just maybe not visible in the photo I have. Mine has the Transgo shift kit in it so it has stiffer springs, etc. The gov mods did increase WOT shift rpm but just not quite high enough IMO. Maybe just needs more gov lightening. Since my stock 350 is all done about 4600 or so anyway it's not real far off. I don't feel like pulling the pan again anytime soon so it will do for now. I don't race it and don't go WOT that much.

Offline 73ss

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Re: Fine tuning Q-jet
« Reply #56 on: May 25, 2022, 04:08:34 PM »
Mine did have the pink paint mark. Also had CZ stenciled on it in white.

Offline 77cruiser

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Re: Fine tuning Q-jet
« Reply #57 on: May 25, 2022, 04:30:44 PM »
I don't know about a CR, if it's like a lot of other low perf. valve bodies it's almost impossible to get the shift points much higher.
The spool sizes are different in a hi perf valve body.
I had a OG & managed to get 6200 1-2 but 5800 2-3 & a bit under 5000 3-4.
Jim

Offline bob69

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Re: Fine tuning Q-jet
« Reply #58 on: May 27, 2022, 08:57:46 AM »
Von, send me a PM with your email and I'll send pics of my vb. The pink paint is obvious, so compare to yours. Hate to see you trying to modify the vb when/if it's one of the low performance models.