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-   -   Swap to tunnel ram, what gains? (https://www.racingjunk.com/forums/showthread.php?t=25720)

prozb 09-16-2009 02:33 PM

Swap to tunnel ram, what gains?
 
I have a shafiroff 582 pro series engine with cfe385 heads. Tha camshaft is a 286-300@50, 810-780 lift crane. Runs a pro systems 1300 and made 1027hp and 800ft-lbs. I have switched to a dart cast rectangular port tunnel ram with 2 1150hp holley carbs. What sort of gains would i expect with this setup? The old setup turned to 7200, where would this new setup make peak power. I would think around 7700. If the duration is a bit small on the cam i could bring the lash in from 0.030 to 0.024 to increase it.

thedude 09-17-2009 06:26 PM

Sure, I'll take a bite as this one. Cam specs sound good, I would tighten up the lash regardless. I always run lash between .023" - .026" on any roller, larger lash numbers make me nervous (anything exceeding .028" & up). Switching over to the tunnel ram should inherently make a few extra HP numbers just by increasing the plenum area and moving the venturi(s) directly over the port will increase the effecientcy of the induction system. Because of the increase in plenum area the engine will obviously want more fuel, signal and response could be effected minimally but in your application it's not a factor. Moving in two 1150's will be a great choice. You should see the peak numbers move up in the RPM range but overall I would suspect that you could see another 15-20HP and 8-10Ft/Lbs. What linkage?....I use Enderle's 2X4 tunnel ram linkage on my engines and I think it's by far the best kit on the market.

hammertime 09-17-2009 06:35 PM

Re: Swap to tunnel ram, what gains?
 

Originally Posted by prozb
I have a shafiroff 582 pro series engine with cfe385 heads. Tha camshaft is a 286-300@50, 810-780 lift crane. Runs a pro systems 1300 and made 1027hp and 800ft-lbs. I have switched to a dart cast rectangular port tunnel ram with 2 1150hp holley carbs. What sort of gains would i expect with this setup? The old setup turned to 7200, where would this new setup make peak power. I would think around 7700. If the duration is a bit small on the cam i could bring the lash in from 0.030 to 0.024 to increase it.

You should see .10 or so in the 1/4,
My motor a nyes pro series 582 orginally had a tunnel ram with 2 rupert alky carbs on it, took it off and put a sniper and a terminator and she woke up :)

What kinda bottom end you have in this motor ? What weight of car is it in ?

prozb 09-17-2009 07:55 PM

I have made up my own linkages for it and it works a treat! The bottom end has a dragonslayer crank, manley rods and JE gas ported pistons. I was actuallyhoping someone would have said i would pick up around 40-50hp. The car weighs 3200 and has run an 8.85@154 with the single plain 1300 setup. I am hoping to run in the 8.60's with the new setup!

zipper06 09-17-2009 08:13 PM

It's very possibly to run the 8.60's with the right gearing and tuneup with a 582". Shown below is a 1951 ford pickup, with a 582" and tunnelram on gas no nitrous. It even has the stock frame but struts, even has ladder bar suspension. It weighs over 3,000lbs and will run 5.30's and 8.40's all day long. If you don't believe it BRING IT ON, to Twin Cities, La. he's owned this truck since 1969 and it's a winner. This is a home built motor, not built by some specialitie engine building shop. Sorry i won't tell you what's in the motor.

Zip.

http://img.photobucket.com/albums/v5...2/100_0720.jpg

hammertime 09-18-2009 04:35 AM


Originally Posted by prozb
I have made up my own linkages for it and it works a treat! The bottom end has a dragonslayer crank, manley rods and JE gas ported pistons. I was actuallyhoping someone would have said i would pick up around 40-50hp. The car weighs 3200 and has run an 8.85@154 with the single plain 1300 setup. I am hoping to run in the 8.60's with the new setup!

50hp peak is possible but not 50avg hp IMO but the tq's should be up also.


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