Tunell raaammm!!!!
01-03-2022 | 08:42 PM
#191
Registered
Joined: Nov 2007
Posts: 166
Likes: 13
From: SC
The stacks have been great....been running this with the Holley HP for about the last 9 years. Bought the Enderle stack from Alkydigger - had the injector bosses cast in and integral thermostat housing. I'm not sure if you can still get them or not. I had to make the vacuum manifold, but did it all under the intake so you can't see it. I have a thread on here somewhere detailing the whole conversion from carb to efi.
01-04-2022 | 10:26 AM
#192
Platinum Member
Joined: Sep 2010
Posts: 1,225
Likes: 209
From: Northern Jersey
Gettrdun,
Not sure on the exact numbers. I dont have the dyno sheets. Motors were done when I bought the boat. Not really interested in opening up motors to stroke them. Im i know im over simplifying it, but figured if there was a decent gain by just switching intakes and tuning, why not.
Not sure on the exact numbers. I dont have the dyno sheets. Motors were done when I bought the boat. Not really interested in opening up motors to stroke them. Im i know im over simplifying it, but figured if there was a decent gain by just switching intakes and tuning, why not.
01-04-2022 | 10:47 AM
#193
Platinum Member
Joined: Sep 2010
Posts: 1,225
Likes: 209
From: Northern Jersey
Probably some but NA 509’s your nearing full potential (within reason) unless you were gonna turn it 6k plus. Where did you peak with current builds/mods? I’m sure many would disagree however I’d target in on stroking them. Then at least you knew going into it you’d see a 75 hp gain min without spending a bunch more money. Just a guess but cost of the tunnels PLUS some costly porting$$$. Could probably stroke for under 3k a side.
The short answer is yes. But at what cost, and what final results are you looking for. Fortunately for me, two of my good friends own a speed shop. Fully equipped with CNC's dyno, and all the machine shop equipment it takes to develop and build engines. 10 years ago when we set out to see how much hp we could make out of a 525 efi based engine we had no idea. We were lucky Dustin was interested enough to tune the computers for us. After many hours modifying the intakes and countless dyno pulls, we cam to the conclusion the intake runners were too long, plenum was too small and all the modifications in the world was not fixing that design. So we went with the Hogan intakes. After about 30 more pulls and having plenum stuffers made we achieved the results on our current dyno sheets. To be honest we could got the same results with the 525 Whipple kits. And a hell of alot cheaper. If you are intent on building NA engines with a 500 efi your first bottleneck is the intakes and throttle body. Just won't flow the air needed. Once you get beyond that cu in. I personally wouldn't go any bigger than 565. Then cylinder heads is going to make you your big numbers, find yourself someone who can support their claims. It definitely is not cheap, but their comes some satisfaction from running away from those 700 stage lll boats.
01-05-2022 | 10:38 AM
#194
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Joined: Oct 2010
Posts: 922
Likes: 128
From: Hemlock, MI
I believe Motortrend did an Engine Masters episode on the stack EFI manifolds recently and even played with stack lengths, but it was on a 350-ish ci SBF I believe, so not quite in realm of what I'd think the stacks would be optimal on (big inch motors). Results were very underwhelming compared to a more conventional intake setup surprisingly.
01-05-2022 | 11:08 AM
#195
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Joined: Feb 2009
Posts: 8,356
Likes: 1,515
From: NW Michigan
Well just figured out how to multi quote. Lol. Anyway, lots of good info here. I know Im over simplifying it, was thinking it would just be cool to have 700hp by just switching intake and tuning. Not sure my exact numbers, I dont have the dyno sheet. Motors were done when I bought the boat. I know Eddie Young tuned it, might be worth a phone call to him, and pick his a brain a bit. Ill probably just leave it alone. Then Ill have to address the bravos.
01-05-2022 | 12:26 PM
#196
Registered
Joined: Jan 2006
Posts: 3,598
Likes: 1,168
From: taxachusetts
Gettrdun,
Not sure on the exact numbers. I dont have the dyno sheets. Motors were done when I bought the boat. Not really interested in opening up motors to stroke them. Im i know im over simplifying it, but figured if there was a decent gain by just switching intakes and tuning, why not.
Not sure on the exact numbers. I dont have the dyno sheets. Motors were done when I bought the boat. Not really interested in opening up motors to stroke them. Im i know im over simplifying it, but figured if there was a decent gain by just switching intakes and tuning, why not.
Well just figured out how to multi quote. Lol. Anyway, lots of good info here. I know Im over simplifying it, was thinking it would just be cool to have 700hp by just switching intake and tuning. Not sure my exact numbers, I dont have the dyno sheet. Motors were done when I bought the boat. I know Eddie Young tuned it, might be worth a phone call to him, and pick his a brain a bit. Ill probably just leave it alone. Then Ill have to address the bravos.
I believe Motortrend did an Engine Masters episode on the stack EFI manifolds recently and even played with stack lengths, but it was on a 350-ish ci SBF I believe, so not quite in realm of what I'd think the stacks would be optimal on (big inch motors). Results were very underwhelming compared to a more conventional intake setup surprisingly.
01-05-2022 | 02:03 PM
#199
Registered
Joined: Mar 2011
Posts: 943
Likes: 277
From: So. Burl. VT.
we run the crower stainless rocker shafts. If I were to run a rocker arm it would also be their stainless one. JMO.
