Mid plate vs. no midplate

colby · 07-15-2015, 08:26 PM

Does anyone have pictures of a legal firewall in FWD converted modified they wouldn't mind sharing?

colby · 07-15-2015, 08:59 PM

http://www.brinkracecraft.com/Galler...e/P3189305.jpg

JHeath · 07-15-2015, 09:47 PM

S/S Cavalier from Racing Junk ad several years ago.

JHeath · 07-15-2015, 10:04 PM

Another one @ P&K Race Cars.

Gary Smith · 07-29-2015, 01:19 PM

Quote:

Originally Posted by JHeath

Another one @ P&K Race Cars.

Wasn't aware you can fab a complete firewall on a FWD GT car. Thought part of the OEM piece needed to be intact.

colby · 07-29-2015, 01:31 PM

Straight from the GT rules, modified is basically the same.

FIREWALL
The lower portion of the OEM firewall may be replaced with steel
of equal or greater thickness than OEM. Chevy Cavaliers, Pontiac
Grand Ams and Sunfires, and Ford Escorts may have firewall
replaced or relocated, provided the measurement from the rear of
the radiator core support to the firewall is 34 inches maximum. For
Chevy Cobalt the radiator core support to the firewall is 33 inches
maximum. For all other vehicles, firewall must be in the original
location. A complete one-piece steel firewall that resembles OEM
must be installed, welded in place, and sealed from the driver
compartment. The firewall must extend to and attach to the floor.
The firewall and mid-plate must be two separate pieces. All motor
plates, mid-plates, etc. must be separate from and may not be
attached to the firewall.

If you look at the stock firewall, there is no way to keep in intact and do an RWD conversion.

SSDiv6 · 07-15-2015, 10:13 PM

Quote:

Originally Posted by colby

Does anyone have pictures of a legal firewall in FWD converted modified they wouldn't mind sharing?

Here you go.

colby · 07-17-2015, 09:17 AM

Would this work?

Mark Markow · 07-20-2015, 11:22 AM

Quote:

Originally Posted by colby

Would this work?

in my opinion I would e-mail the drawings to the tech department at nhra, or your div. tech director. to get an approval, and save or print the e mails. so if down the road there is a problem, you have some correspondence to show.

colby · 07-29-2015, 09:55 AM

Just got word back from NHRA that the design would be acceptable. The spacing the model shown was exaggerated slightly to help show that there was a separation of the firewall and midplate. In reality the front surface of the midplate will only be 1" from the firewall. With the LS style engine they actually have no bellhousing flange like a traditional SBC, so the mass of the engine is already offset to the rear over an inch. The engine really has to be offset from the firewall or the head will basically be touching it.

07-15-2015, 08:26 PM	#1
colby Junior Member Join Date: Oct 2014 Location: Noble, OK Posts: 54 Likes: 0 Liked 0 Times in 0 Posts	Re: Mid plate vs. no midplate Does anyone have pictures of a legal firewall in FWD converted modified they wouldn't mind sharing?

07-15-2015, 08:59 PM	#2
colby Junior Member Join Date: Oct 2014 Location: Noble, OK Posts: 54 Likes: 0 Liked 0 Times in 0 Posts	Re: Mid plate vs. no midplate http://www.brinkracecraft.com/Galler...e/P3189305.jpg

07-15-2015, 09:47 PM	#3
JHeath Senior Member Join Date: Jul 2004 Location: Minneapolis Posts: 786 Likes: 2,876 Liked 370 Times in 101 Posts	Re: Mid plate vs. no midplate S/S Cavalier from Racing Junk ad several years ago. Attached Thumbnails __________________ Jerry Heath I/S '93 Cobra FS/J 2010 Mustang "Ebay CJ" Last edited by JHeath; 07-15-2015 at 10:06 PM.

07-15-2015, 10:04 PM	#4
JHeath Senior Member Join Date: Jul 2004 Location: Minneapolis Posts: 786 Likes: 2,876 Liked 370 Times in 101 Posts	Re: Mid plate vs. no midplate Another one @ P&K Race Cars. Attached Thumbnails __________________ Jerry Heath I/S '93 Cobra FS/J 2010 Mustang "Ebay CJ"

07-29-2015, 01:31 PM	#6
colby Junior Member Join Date: Oct 2014 Location: Noble, OK Posts: 54 Likes: 0 Liked 0 Times in 0 Posts	Re: Mid plate vs. no midplate Straight from the GT rules, modified is basically the same. FIREWALL The lower portion of the OEM firewall may be replaced with steel of equal or greater thickness than OEM. Chevy Cavaliers, Pontiac Grand Ams and Sunfires, and Ford Escorts may have firewall replaced or relocated, provided the measurement from the rear of the radiator core support to the firewall is 34 inches maximum. For Chevy Cobalt the radiator core support to the firewall is 33 inches maximum. For all other vehicles, firewall must be in the original location. A complete one-piece steel firewall that resembles OEM must be installed, welded in place, and sealed from the driver compartment. The firewall must extend to and attach to the floor. The firewall and mid-plate must be two separate pieces. All motor plates, mid-plates, etc. must be separate from and may not be attached to the firewall. If you look at the stock firewall, there is no way to keep in intact and do an RWD conversion. Last edited by colby; 07-29-2015 at 01:34 PM.

07-17-2015, 09:17 AM	#8
colby Junior Member Join Date: Oct 2014 Location: Noble, OK Posts: 54 Likes: 0 Liked 0 Times in 0 Posts	Re: Mid plate vs. no midplate Would this work?

07-29-2015, 09:55 AM	#10
colby Junior Member Join Date: Oct 2014 Location: Noble, OK Posts: 54 Likes: 0 Liked 0 Times in 0 Posts	Re: Mid plate vs. no midplate Just got word back from NHRA that the design would be acceptable. The spacing the model shown was exaggerated slightly to help show that there was a separation of the firewall and midplate. In reality the front surface of the midplate will only be 1" from the firewall. With the LS style engine they actually have no bellhousing flange like a traditional SBC, so the mass of the engine is already offset to the rear over an inch. The engine really has to be offset from the firewall or the head will basically be touching it.