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2Likes
01-22-2016, 02:12 PM
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CC Member
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Join Date: Apr 2012
Location: Bay Area (Peninsula),
CA
Cobra Make, Engine: ERA 427, 427/487 side-oiler
Posts: 1,248
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Not Ranked
Quote:
Originally Posted by Bernica
Yup. Bucking and snorting around town until you get over 5k rpm is fun, but...
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It's not that bad. Actually it's pretty decent. But living in fairly congested NorCal, you *cannot* speed much. And if I get on the car, I'm going 90 MPH in a few seconds. The reality is that I spend most of my time at 2500 RPM, and occasionally get it in the higher RPM range, briefly. The more I think about it, peak of 5800 RPM and redline of 6300 would be perfect.
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01-22-2016, 02:12 PM
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CC Member
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Join Date: Dec 2011
Location: West Chester,
PA
Cobra Make, Engine: ERA #795 427 S/C completed Jan. '14 - '68 FE 427 side oiler
Posts: 1,051
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Not Ranked
Lippy,
My engine peaks at 5,800. Love the low-end torque for cruising around. I'm sure you'll enjoy that.
Kevin
__________________
"Anyone who drives faster than you is a maniac and anyone who drives slower than you is an idiot" - George Carlin
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01-22-2016, 02:19 PM
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Half-Ass Member
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Join Date: Jun 2005
Cobra Make, Engine: ERA #732, 428FE (447 CID), TKO600, Solid Flat Tappet Cam, Tons of Aluminum
Posts: 22,005
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Not Ranked
I have my rev limiter set at 6400 and bounce off it maybe once a year or so. There's really no reason for me to even go that high other than the fact that it sounds cool.
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01-22-2016, 02:20 PM
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CC Member
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Join Date: Aug 2013
Location: Canandaigua,
NY
Cobra Make, Engine: SPF MKII Riverside Racer FIA
Posts: 2,499
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Not Ranked
If most of your driving is in the 2500 rpm range it makes sense running a cam that starts producing power at around 2000 rpms. It is not good for a car to be constantly running underneath the cam's operating range.
Good luck with it.
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01-22-2016, 02:21 PM
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CC Member
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Join Date: Dec 2001
Location: Louisville,
KY
Cobra Make, Engine: I'm Cobra-less!
Posts: 9,417
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Not Ranked
According to Jeff, it doesn't buck and snort much at all. However, where he lives, he spends all his time at 2000-2500 and doesn't have much room to really stretch it out. This engine doesn't want to start going hard until 5000-6000 rpm and it's just not prudent to keep it there all the time.
He's got some $$$$ Isky bushed solid roller lifters and some titanium retainers, so if he's up for the cam swap, I'm going to try to make it so that we just need to switch one or two things...
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01-22-2016, 02:28 PM
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Senior CC Premier Member
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Join Date: Nov 2004
Location: SoCal,
CA
Cobra Make, Engine: CSX #4xxx with CSX 482; David Kee Toploader
Posts: 3,574
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Not Ranked
Quote:
Originally Posted by lippy
It's not that bad. Actually it's pretty decent. But living in fairly congested NorCal, you *cannot* speed much. And if I get on the car, I'm going 90 MPH in a few seconds. The reality is that I spend most of my time at 2500 RPM, and occasionally get it in the higher RPM range, briefly. The more I think about it, peak of 5800 RPM and redline of 6300 would be perfect.
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I agree with all above. While it is fun nailing 6,000+, where I live in SoCal that is rarely possible (well, yes of course I have done it! and there isn't enough road to do it in 4th gear unless I'm on the freeway at around 4am (and I would never do that! .
__________________
All that's stopping you now Son, is blind-raging fear.......
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01-22-2016, 02:29 PM
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Senior CC Premier Member
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Join Date: Nov 2004
Location: SoCal,
CA
Cobra Make, Engine: CSX #4xxx with CSX 482; David Kee Toploader
Posts: 3,574
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Not Ranked
BTW, I'm running 3:31 rear end and a WR toploader, so it takes time to get up there!
__________________
All that's stopping you now Son, is blind-raging fear.......
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01-22-2016, 05:30 PM
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CC Member
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Join Date: Nov 2007
Location: Clayton,
IN
Cobra Make, Engine: ERA 838
Posts: 1,123
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Not Ranked
What is your HP and torque today and then what is your target? I am just curious what didn't work for you and now what you think.
John
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01-22-2016, 05:47 PM
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CC Member
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Join Date: Jun 2009
Location: Boston,
MA
Cobra Make, Engine:
Posts: 361
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Not Ranked
call Mike Forte in Framingham Ma...Forte Parts ...he replaced the cam in my FE ERA and i know the motor didn't come out...i believe the hood, radiator etc came off...i believe he had plenty of room with those items out
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01-22-2016, 07:33 PM
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CC Member
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Join Date: Apr 2012
Location: Bay Area (Peninsula),
CA
Cobra Make, Engine: ERA 427, 427/487 side-oiler
Posts: 1,248
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Not Ranked
Quote:
Originally Posted by Grubby
What is your HP and torque today and then what is your target? I am just curious what didn't work for you and now what you think.
John
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Peak HP is 640 at 6600 and peak TQ is 590 I think at 5800. Just hard to use that where I live, off a track. I want to move peak HP down to 5800 and gain low end torque and cruise efficiency.
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01-23-2016, 06:37 AM
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CC Member
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Join Date: Sep 1999
Posts: 356
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Not Ranked
Rest a laser pointer right where the X braces meet and aim it at the front of the block, it will let you know immediately how much you need to raise the block for the cam to clear they X brace.
Dean
__________________
RUMs are like a woman in Stiletto heals, you know they are going to put you in the poor house, but that has never stop anyone from pursuing one.
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01-23-2016, 09:34 PM
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CC Member
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Join Date: Apr 2012
Location: Bay Area (Peninsula),
CA
Cobra Make, Engine: ERA 427, 427/487 side-oiler
Posts: 1,248
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Not Ranked
Looks like my estimate was right. I removed the alternator, water pump, radiator (had to drop the roll bar to do this), balancer, and cam cover. Removed the engine mount nuts and loosened the radiator mount bolts, jacked the engine up about 2", and the cam slid right out. No tool needed, just put a bolt in the cam to get a handle on it. Complete PITA, but now it's done.
So I will now swap (6,600 RPM peak, 640/570) this cam for a more streetable one (5,800 RPM peak, guessing 610/610), keeping the solid roller lifters for a more aggressive cam profile, lowering spring pressure a bit.
But the one thing I'm deliberating is intakes. My current Victor is ported really beautifully but is optimized for higher RPMs. I could go for a Performer RPM, but I'm hesitating because the Victor is such a killer piece, it looks great, and I'm told big engines can handle single plane intakes with little loss at low RPMs.
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01-24-2016, 05:04 AM
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CC Member
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Join Date: Apr 2009
Location: Little Rock area,
AR
Cobra Make, Engine: ERA Street Roadster #782 with 459 cu in FE KC engine, toploader, 3.31
Posts: 4,521
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Not Ranked
Brent should have some thoughts on that. I assume you also have some heavily worked heads with big flow numbers designed more for higher rpm. He would probably know considering the heads, if the intake switch would make the expected difference or be nulified by the heads.
Have you thought about going hydraulic roller now? I guess that might require digging deeper into the engine however to reverse the internal oiling restrictions.
If you have access to Jay Brown's book the Great FE Intake Comparo, it has notes on some pertinent differences in the two intakes. Compared to the Victor which has a level carb pad, the RPM mounts the carb at the OEM slant towards the front. The RPM is probably about an inch lower at the carb pad. Also the carb mounts about 3/8 inch further to the rear on the RPM. On his stroker 427, ported MR head test engine the Victor made about 20 HP more than the RPM at 7000 rpm versus 6400 rpm for the RPM. The RPM made about 10 ft-lbs more torque and both peaked around 5000 - 5100 rpm. This was just one engine combination he tested both intakes on that was otherwise of the same details. He also noted that the RPM did have a dip in the torque curve at lower rpm that created a soft spot.
Last edited by DanEC; 01-24-2016 at 05:29 AM..
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01-24-2016, 05:34 AM
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CC Member
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Join Date: Aug 2013
Location: Canandaigua,
NY
Cobra Make, Engine: SPF MKII Riverside Racer FIA
Posts: 2,499
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Not Ranked
Lippy,
I would hold off on changing intake manifolds right now. You are probably going to have to re-adjust your carb to the new cam. I would try that first before you start adding more work to your plate. Also, changing out the intake manifold will be a major PITA with the engine in it's current orientation (i.e., canted backwards). The intake manifold needs to be installed with the engine horizontal to ensure proper fit and to maintain the gaskets in the correct place. If you decide to do it, you would first return the engine to it's fully installed position. It's your call.
let's see what Brent says.
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01-24-2016, 07:46 AM
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Senior Club Cobra Member
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Join Date: Jun 2003
Location: West Linn,
OR
Cobra Make, Engine: ERA #684, 428 FE, TKO600
Posts: 1,378
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Not Ranked
I just reinstalled the intake manifold on my 428 big block and came up with a procedure that you might want to consider for initial placement of the manifold. Still a 2 person job but this helped reduce the paranoia about getting it indexed.
Took two 5 inch 3/8 X 16 bolts and cut the heads off, smoothed and rounded the cut ends and slotted them to allow using a screw driver to assist in their removal.
Installed the modified bolts in the front and rear intake bolt holes in the head. Lifted he manifold high enough to get the modified bolts in the front and real holes of the intake manifold and then slowly slid it down the modified bolts until it was resting on the heads. Installed the rest of the bolts finger tight and then removed the modified bolts and replaced them with the proper bolts for those locations.
Paid attention to the admonitions about the extra sealant around the water jacked holes and in the corners at the front and rear of the edge gasket areas and installed the distributor temporarily while tightening the bolts down to insure the distributor hole remained in alignment while the bolts were being tightened.
Did a test run dry just to make sure everything cleared and it went very smoothly.
The whole thing was driven by my concern about getting the front and rear edges lined up properly with the thick bead of sealant that is used instead of the gaskets supplied with the manifold gasket set per Edlebrock's recommendations.
DonC
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01-24-2016, 07:48 AM
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Half-Ass Member
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Join Date: Jun 2005
Cobra Make, Engine: ERA #732, 428FE (447 CID), TKO600, Solid Flat Tappet Cam, Tons of Aluminum
Posts: 22,005
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Not Ranked
Quote:
Originally Posted by lippy
So I will now swap (6,600 RPM peak, 640/570) this cam for a more streetable one (5,800 RPM peak, guessing 610/610), keeping the solid roller lifters for a more aggressive cam profile, lowering spring pressure a bit.
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Are those numbers right? You're dropping 30 horses and gaining 40 in torque?
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01-24-2016, 07:53 AM
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CC Member
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Join Date: Apr 2009
Location: Little Rock area,
AR
Cobra Make, Engine: ERA Street Roadster #782 with 459 cu in FE KC engine, toploader, 3.31
Posts: 4,521
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Not Ranked
Quote:
Originally Posted by 1795
Lippy,
I would hold off on changing intake manifolds right now. You are probably going to have to re-adjust your carb to the new cam. I would try that first before you start adding more work to your plate. Also, changing out the intake manifold will be a major PITA with the engine in it's current orientation (i.e., canted backwards). The intake manifold needs to be installed with the engine horizontal to ensure proper fit and to maintain the gaskets in the correct place. If you decide to do it, you would first return the engine to it's fully installed position. It's your call.
let's see what Brent says.
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I believe his current manifold is off anyway in order to get the cam out. Since he was working on pan rail reinforcements last week, I suspect he just has a bare short block sitting in the car at the moment. And once the new cam is in he can set the engine back down. Good comment about having the engine as level as possible to keep the manifold or gaskets from sliding.
Edit - should have said long block.
Last edited by DanEC; 01-24-2016 at 09:37 AM..
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01-24-2016, 09:26 AM
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CC Member
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Join Date: Apr 2012
Location: Bay Area (Peninsula),
CA
Cobra Make, Engine: ERA 427, 427/487 side-oiler
Posts: 1,248
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Not Ranked
Quote:
Originally Posted by DanEC
Brent should have some thoughts on that. I assume you also have some heavily worked heads with big flow numbers designed more for higher rpm. He would probably know considering the heads, if the intake switch would make the expected difference or be nulified by the heads.
Have you thought about going hydraulic roller now? I guess that might require digging deeper into the engine however to reverse the internal oiling restrictions.
If you have access to Jay Brown's book the Great FE Intake Comparo, it has notes on some pertinent differences in the two intakes. Compared to the Victor which has a level carb pad, the RPM mounts the carb at the OEM slant towards the front. The RPM is probably about an inch lower at the carb pad. Also the carb mounts about 3/8 inch further to the rear on the RPM. On his stroker 427, ported MR head test engine the Victor made about 20 HP more than the RPM at 7000 rpm versus 6400 rpm for the RPM. The RPM made about 10 ft-lbs more torque and both peaked around 5000 - 5100 rpm. This was just one engine combination he tested both intakes on that was otherwise of the same details. He also noted that the RPM did have a dip in the torque curve at lower rpm that created a soft spot.
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Dan,
I don't have the book but I may buy it. Curious if you might know what he said about the difference between the RPM and Victor at lower revs, on a big cube engine. I know the Victor is better at the top end, and it would be good to know if you lose a lot at the low end.
I don't think it would be a problem installing a different manifold, but the new one wouldn't have the porting and port matching work of the Victor.
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01-24-2016, 10:01 AM
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CC Member
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Join Date: Apr 2009
Location: Little Rock area,
AR
Cobra Make, Engine: ERA Street Roadster #782 with 459 cu in FE KC engine, toploader, 3.31
Posts: 4,521
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Not Ranked
I think the book would be real interesting to you considering all that you're doing on the car. He has a pretty good description of each intake and test results (engine dyno) on several different configuration mules.
He said the RPM was probably the best all around and most versatile manifold for performance and finished in the top 3 single carb intakes on the 427 SO and 427 stroker motors. He noted about a soft spot down low but said it was most pronounced on the 410HP 428 CJ and not as much so on the more modified engines. He said port matching it boosted HP notably - but resulted in some loss of torque - but again this was most noted on a 390 stroker engine combo and he didn't mention it on the 427 engines. He made a point that this is a dual plane manifold but doesn't always behave like a typical dual plane manifold.
Just eyeballing the charts the RPM started exceeding 550 ft lbs of torque at about 3200 rpm (going up to just under 600 ft lbs at 5,000 but falling off slowly) while the Victor was kind of flat around 550 from about 3,800 until about 4,400 rpm and then started rising to just under 600 somewhere around 5,000. The RPM torque curve does look much broader and less peaky. It looks like the torque falls off slower past 5,000 with the RPM also.
From looking at this I don't think I would expect to pick up any additional torque with an RPM, but you probably won't lose any either (or much) and you should have a much broader torque curve.
I can try to scan a few pages of this later today.
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01-24-2016, 10:52 AM
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CC Member
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Join Date: Dec 2001
Location: Louisville,
KY
Cobra Make, Engine: I'm Cobra-less!
Posts: 9,417
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Not Ranked
A few thoughts....
Lippy's engine does not have oil restrictors. I don't restrict oil to the lifters on a street engine. He also has about $1200 worth of Isky EZ Roll Red Zone bushed lifters, so we didn't want to give those up to change to a hydraulic roller.
Jay's book is a nice chunk of information, but a manifold comparison on one engine will by no means give data for every combination out there. I do believe he did a lot of his testing on a 428 (??). Jeff's engine is about 60 inches bigger.
Now, speaking generally, a larger engine will make short work of a larger intake. A Victor intake on a 390 would exhibit a lot of the "bad manners" that people think about with single plane intakes. However, a Victor intake on a 487 wouldn't be that big of a deal whatsoever.
The catch is that Jeff's heads flow almost 350 cfm and have very tall/wide ports to accomplish that. His intake has been fully port matched and worked in the plenum. The difference between it and an out-of-the-box Victor is *substantial*.
With that being said, this engine was originally designed to be a higher strung engine. Pulling it down to a much lower power band would probably be highly complimented by a Performer RPM (especially with a 1" tapered spacer - we've seen up to 30 hp bump with those on the dyno).
However, there are a couple things that would complicate that swap. For one, the Victor is already milled and cut to fit the heads. It's very possible to put a Performer RPM on and the ports not line up, which would necessitate milling the flanges and/or the valve cover rails. The fact that it's not ported or port matched probably wouldn't make much difference here. Velocity is king and you want high velocity at low rpms on the street.
All-in-all, my gut tells me the Performer RPM would be a better match, but if he were to put the Victor back on, he would probably just notice some throttle response lag.
Everyone tends to forget that these cars are 2500 lb street-legal race cars. You make compromises. If you lose 10-20 hp, it's not going to be noticeable. If you lose 10-20 lb-ft, it's not going to be noticeable. What is noticeable is having the power available and available immediately in the rpm ranges that you spend most of your time driving in.
If I remember correctly, Lippy's car is also geared lower in the rearend (3.70-3.73, am I right?) and is running a TKO 600 which could potentially alleviate any throttle response issues. It's not like it's a 3.31 rear with a close ratio Toploader...
Last edited by blykins; 01-24-2016 at 10:54 AM..
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