Trans shield


Well-Known Member
Nov 21, 2021
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Montgomery County PA
Can anyone recommend a trans shield or blanket for a small block 727? Be nice to hear some reviews before I purchase one.
The CSI shield is pretty popular but I can honestly say, I wish I had a blanket over that shield. A&A makes a blanket that fits on our 727s and is a good fit. Not a universal one. The A&A is cheaper than a shield I believe and will give you more room when installing the trans in the car. The only reason I haven’t ditched my shield and went to a blanket is because my trans tunnel is removable so it makes installation easy. If you do decide to go with a CSI shield make sure you get bolts with 3/8 12 point head because a standard bolt with 7/16 6 point will cause you lots of grief when you go to put a wrench or socket on the bolt and try to tighten it.

Again, I’d recommend an A&A blanket over a CSI shield.
I run a blanket, or used to. 904 now, just personal opinion, but I believe a blanket would control an explosion better. I have seen pictures of holes through a shield. Just my gut feeling.
I too would prefer a blanket…..BUT it doesn’t cover the rule for flex plate/flywheel shield, that is why the CSR shield is the “go-to” for anyone running 9.99 or faster with a torqueflight.

like Demon I have a removable trans tunnel and that is due to when I was running a 727 the CSR shied was not going to fit my car.

727….. please tell me you have an aftermarket front drum. it’s also my “hunch” that a blanket will absorb energy better than the shield.

CSR shield will fit a 904 with stock floors. It’s tight and may require some massaging, but it will fit.

I run a blanket, or used to. 904 now, just personal opinion, but I believe a blanket would control an explosion better. I have seen pictures of holes through a shield. Just my gut feeling.
I know all cars seem to be a little different but I had to really beat the floor for clearance to get my CSI shield on a 904. My exhaust is super close to the pan ran and I can't see how a blanket would have worked well for me. My shield came with the mentioned 12 point bolts. I cut holes in the firewall to access them with a socket. I should have done that long before the shield, it sure shaves some time off a transmission removal.

In my case a shield on a 727 would take some floor surgery on the passenger side. I don't think it matters but my car came with a 727.
I am not running an after market drum yet.....not running that fast but will be upgrading when new motor goes in. Just want to be cautious with what I'm running now.
Definitely want to run a shield or blanket then. I know A body mentioned it above, and from what I’m told, the blanket will contain an explosion better than the shield.

What all other upgrades do you have done to the trans at this point?
Heavy duty sprague and clutch pack. 4500 stall converter with rmvb. It sounds like a lot of racers are running the 904 trans......surprised to see that
Ya I’m shocked to see that as well. However, technology and new upgraded parts I’m sure have evolved that like many other things.

For what it’s worth, not that I would recommend it or anyone else would recommend, but I know people who have ran 9s and 10s for many of years with nothing more than a stock front drum, cheetah RMVB, and bolt in 12 element sprag. But I would certainly be upgrading that drum in the future.
I picked up a solid 2-3 10ths going from 727 to 904. Now, I changed from a aftermarket steel driveshaft to an aluminum one. 6-7 lbs right there. Then I went low gear set and bumped my flash from 3340 to 3500 rpm. So some of the gain is in there, but a 904 built well will live for a very long time behind something making much more power than I am. I broke a sprag in my 727. I was in staging and it took longer for it to drop into gear. I tried to get it to do it again and it wouldn’t. Felt weird in the burn out. Aborted the run, couldn’t get it to really act up, until I got it to pop while in low. Good enough for me! Rolled all the springs, cracked the case, broke a roller in half.
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It really isn’t a power thing. It’s loading and unloading the driveline. Then rpm blows it up. The drum will spin 2 1/2 times engine rpm.
Did any of you guys notice a temperature increase with either the blanket or shield?
Sorry I’m not help but I will say aftermarket support sure is nice. I have three of these used to be geared 1.98, 1.80, and a 1.69 but I sold the 1.98 to calm the car down and bought another 1.80. Bellhousing can change from big block Mopar to small block Mopar in about 4 minutes. On my 727’s I’ve had the CSR shield and really liked and blankets but I’m betting the blankets aren’t 1/2 as thick and heavy as they used to be. That Lakewood blanket was a beast.




My car is 3353 with me in it and runs 117 mph. Calculators have it at 390-400? I can’t hit the tire like a normal car, so I’m soft down low and mph a bit more the average car for the E/T
I run a 904 that is stock other than a cheetah valvebody and an A&A spring pack. My car weighs 3550 and has been lots of low 1.4 60s. Easy way to pick up .1 or more. I ran a 727 the same way for over 10 years. Nothing was wrong with the 727 I just wanted to go faster and lose the lbs.
Did any of you guys notice a temperature increase with either the blanket or shield?
With the shield, I have never got my trans hotter than 210 and that is after 9 rounds of racing and on the return road where the trans will build most of its heat after the run. Goin down the track it’s never been over 180-190
I still have this 904 blanket from the mid 90’s that Chuck Lofgren had made and you could get a SFI approved version. 16.5x12” and covers the critical area of the torqueflight. I’m betting my red 727 one is probably still on my old racecar.

I’ve had close experiences with stock 727 drum failures on two occasion. Both experienced gear breakage at the launch shocking the rear roller clutch. The damage to the car and drivers is something you won’t soon forget. All our 727 got billet front drums and blankets after witnessing that.

my incredibly stock component 904 is at 93 passes and still working great! Tore it apart 10 passes ago and all looked good. Threw it back together and will run it for a little while.

I've used both a TCI blanket and CSR shield in a 75 duster with 440 and 727. The blanket seemed to keep more heat in the trans but is easier to install. The CSR shield fits nicer, but is harder to install the bell bolts. I ended up drilling 4 holes in my floorpan/firewall to access the 4 bell bolts and have plugs to seal them back up. I did have to beat the firewall/floorpan seam flat for more clearance with the CSR shield.
I jumped at a screaming-deal on an ATI Turbo-400, with all the goodies [it had 10 passes on it]. Since I already had it, it went into the Krusty build. I bought it with a BB/hemi bell, but just ordered a SB bell from ATI. After engine-dyno, I have to send the converter to ATI for it's new usage. Gonna see how well it works...hopefully, soon.

The aftermarket support for the bowtie stuff, can be appealing.

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The aftermarket definitely supports the Chevy stuff more. It’s just pretty costly to switch over from 727/904 to a glide, or T400. The shield or blanket costs much less than totally switching to a T400 or Glide. Pretty much the main reason I’ve never swapped to a glide.