Tunnel Ram

[cudabob496]

anyone put a tunnel ram on a Mopar Big Block?  Supposed to be
at good 20 hp gain throughout the rpm range, plus, would look
pretty cool.

[Chryco Psycho]

They do work well

[cudabob496]

They do work well

On my 496, I assume I should use the Weiand, and what size/type carbs do you recommend??

[Chryco Psycho]

I played with them a bit , one car I worked on was a 340 with a pair of 600 cfm carbs ,  1200 cfm Overkill for a 340 right !
 We tuned the daylights out of them & ran some times at the track & switched over to RPM Air Gap with an 800 , honestly my bet was the car would be faster with the RPM & the 800 .
 Nope the timeslips didn't lie , it truly was faster & as drivable with the tunnel ram , seriously not what I expected at all .
 Various ways to set up a tunnel ram , probably the best drivability is with a smaller plenum & vacumm secondary carbs , but you can go IR & have 2 carbs with mechanical secondaries that all open equally right off idle .
 I suspect that now an EFI setup with 1200 cfm & multiport injection would kick the tunnel rams ass especially on a good intake like the Victor or M1 using a dry intake & a 1000 more tuning variables with fuel timing etc it seems to me nothing carburated could come close .
 I am not sure what tunnel ram intakes are even available now . Weiand was a good piece though ,, you could use 6 pack carbs with all mechanical not vacuum . 2 4 bbls dominators are 3 circuit carbs & work well , they do make 750 cfm Dominators , Proform or Quick Fuel would be good choices too .

[cudabob496]

thanks CP! What do you think of this setup for my car?

http://www.summitracing.com/parts/cmb-03-0186/overview/make/plymouth

[Chryco Psycho]

Looks OK , seems expensive though , you should be able to buy carbs like that for $200 each , it would be nice to have the quick change seconadry spring feature , intake & linkage for 600 seems high , maybe it isn't but I would shop around a bit .

[HP2]

I played with them a bit , one car I worked on was a 340 with a pair of 600 cfm carbs ,  1200 cfm Overkill for a 340 right !
 We tuned the daylights out of them & ran some times at the track & switched over to RPM Air Gap with an 800 , honestly my bet was the car would be faster with the RPM & the 800 .
 Nope the timeslips didn't lie , it truly was faster & as drivable with the tunnel ram , seriously not what I expected at all .

Hot Rod did a similar test on a 383 about a decade ago. They ran nearly every combo of intake they could get their hands on, including two or three different tunnels rams. Their results were the same - tunnel rams produced the most power and torque by a pretty fair margin across the power band, and this occurred at the bottom of the test range, not just up high in the rpm range. But tuning it is the ley to making them work well. 

I used to have a big excel sheet on it with all the results graphed out. I might  try to find it and see if I can post it up.

[cudabob496]

http://www.forabodiesonly.com/mopar/showthread.php?t=225886

[cudabob496]

http://www.jegs.com/i/Weiand/925/1987K/10002/-1?parentProductId=#moreDetails

[Oldschool]

http://www.jegs.com/i/Weiand/925/1987K/10002/-1?parentProductId=#moreDetails

As advised on the first page of responses shown in the link to FABO, I also recommend the 660 center squirters. I ran those on my old 426 tunnel rammed '65 A-990 Coronet.  Mill the air horns off and they are perfect for the Weiand manifold. Easy to tune too....

[cudabob496]

I spoke with Holley tech today.
They recommend these carbs for my street application:

http://www.jegs.com/i/Holley/510/0-1850C/10002/-1?parentProductId=743607#moreDetails

Said only need choke on front carb, if at all. He said milling off the choke towers might get me 5 cfm per carb.
He said the present spring in the vacuum sedondaries should be about right.

I guess Holley bought out Wieand.

I gotta do some measuring, to see how far above hood the air cleaners will be.

[cudabob496]

these stacks look cool

http://www.bing.com/images/search?q=tunnel+ram+cuda&view=detailv2&&&id=D05F0FFB430E0591A664594920BDC74A972B1DB3&selectedIndex=14&ccid=wfciUaJz&simid=608015314971855848&thid=JN.XaudWhEj7lTVxNLoND2XMA&ajaxhist=0

http://www.bing.com/images/search?q=tunnel+ram+cuda&view=detailv2&&&id=88F46E4389559111A240A0630CE69D99F4731ED8&selectedIndex=64&ccid=aArKuv7o&simid=608030304415712549&thid=JN.fYXKWtLV9ywRVJfvGbUt5A&ajaxhist=0

[cudabob496]

Hmmm, same color as my car.  Obviously this change would be 90% for looks, and not performance!


http://image.carcraft.com/f/featuredvehicles/ccrp_0501_1970_plymouth_barracuda/31484781/ccrp_0501_02%2B1970_plymouth_barracuda%2B.jpg

[cudabob496]

As advised on the first page of responses shown in the link to FABO, I also recommend the 660 center squirters. I ran those on my old 426 tunnel rammed '65 A-990 Coronet.  Mill the air horns off and they are perfect for the Weiand manifold. Easy to tune too....

does Holley make a 660 center squirter?

[Chryco Psycho]

They used to , probably still do