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Originally Posted by Full Force
(Post 4483794)
yea, I hear ya, guess with a tad more HP figure if nothing else it would still go same easily... oh well...
took trans shift valve out tonight, gonna toss my valve from spare trans in tomorrow and see if I have reverse, that will determine what I do with engines... Either way, ultimately, those 565's, ate chit, and and were tore up. You bought all new components, and while part of the goal was to go faster, the other part was to be reliable. Seems like this summer, you were out every weekend with the new builds. So at least you have that going for you. Nobody's going fast on the trailer sitting in storage with a broken engine. |
Originally Posted by MILD THUNDER
(Post 4483790)
Even at 1.16HP per ci, 25 cubes might be worth, 30hp right off the bat.
What I find really strange, MT has mentioned this too a few times, is FF's dyno #'s up top were like 600-800rpm later is only 8 addt'l hp. This is weird. Something is struggling. Airflow or fuel or mechanical. |
As you know I am pretty much on board with all that when funds are there, very tempted to leave it be another year or two providing things compression test and leakdown good, then address ALL that at refresh time, unless I find a deal on headers if nothing else... I can do that with minimal effort, spend winter painting fairing, repairing indicator cables, putting my new gauges in and adding EGT, that alone is a decent amount of work and cost... it's always a battle lol
Originally Posted by MILD THUNDER
(Post 4483783)
If I were a betting man, I'd be willing to bet, if Tim had dyno'd his engines, with no accessories, some 2 1/8, or 2.25 dyno headers, with a decent collector setup, dumping into some big ole straight flex pipes, some tweaking on the dyno with carb spacers and stuff like that, he would have got much closer to his promised setup. Maybe not hit the target, but not 70hp away.
I'm going to stick with my gut feeling advice wise, and say that ,I feel his exhaust system is hurting him, he'd be better off with a dominator carb (got blasted for suggesting that during his build here), and a little more camshaft. Not a ton, but a little more. If his boat was mine, and I was going to be making changes, I would be looking for a decently priced set of used headers, a different camshaft, taking the heads off, getting a nice valve job done with a back cut on the intake valves, ditching the MSD ready to run distributors, and figuring a way to get as much fresh air into that bilge as possible. I'd also be putting the scorpion rockers on ebay. JMO. I'd forget about what everyone else is doing. If I followed what everyone else was doing with their 454's, they'd have been in the dumpster a long time ago. |
Originally Posted by SB
(Post 4483799)
I've harped on this since day one. Will have more power everywhere if heads support it, which at this level this equals a yes.
What I find really strange, MT has mentioned this too a few times, is FF's dyno #'s up top were like 600-800rpm later is only 8 addt'l hp. This is weird. Something is struggling. Airflow or fuel or mechanical. I'd like to say it was the camshaft. But, there certainly can be something else going on. Unfortunately, there just wasn't alot of time there on the dyno, to really play with things. Tim pretty much had 1 day to dyno 2 engines, and head back to ohio. The dyno numbers, seemed to pretty much show, what he was, or wasn't seeing, in the boats performance. |
for sure not fuel or airflow, I could say maybe airflow in boat but certaintly not dyno, added another vent to bilge, also ran with hatch open 10" for lots of fresh air...
fuel was good on dyno and also boat, widebands and pressure gauges tell me that. mechanical? not sure unleaa valvetrain is bad, but after 65 hours I think I would know... might be wrong... that's where leakdown will tell me also..
Originally Posted by SB
(Post 4483799)
I've harped on this since day one. Will have more power everywhere if heads support it, which at this level this equals a yes.
What I find really strange, MT has mentioned this too a few times, is FF's dyno #'s up top were like 600-800rpm later is only 8 addt'l hp. This is weird. Something is struggling. Airflow or fuel or mechanical. |
Prochargers!!!!!!!!! Done!
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You know what`s gonna suck even worse, you go thru the trouble and $$ of pulling motors, new exhaust, cams, go thru heads etc etc and go 1 mph faster.
WAP WAP WAAAAAAAA!!!!! |
exactly, so I may just leave it, I may even just fix that trans next week, put the boat away running and do easy chit for once, restore my 85 Mustang GT I just bought back I had 20 years ago... easy winter haha
Originally Posted by ICDEDPPL
(Post 4483807)
You know what`s gonna suck even worse, you go thru the trouble and $$ of pulling motors, new exhaust, cams, go thru heads etc etc and go 1 mph faster.
WAP WAP WAAAAAAAA!!!!! |
Blower motors.. you wanna go faster tomorrow just swap some pulleys, add a little jet ... boostane if you wanna get crazy or run some granny pulleys for everyday reliability.
http://www.birdsonggregory.com/wordp...ing_agency.jpg |
Originally Posted by SB
(Post 4483799)
I've harped on this since day one. Will have more power everywhere if heads support it, which at this level this equals a yes.
What I find really strange, MT has mentioned this too a few times, is FF's dyno #'s up top were like 600-800rpm later is only 8 addt'l hp. This is weird. Something is struggling. Airflow or fuel or mechanical. |
Originally Posted by MILD THUNDER
(Post 4483802)
According to the widebands, the fuel mixture was pretty consistent on the dyno. The airflow turbines didn't seem to be showing anything weird. Both engines were showing the same story.
I'd like to say it was the camshaft. But, there certainly can be something else going on. Unfortunately, there just wasn't alot of time there on the dyno, to really play with things. Tim pretty much had 1 day to dyno 2 engines, and head back to ohio. The dyno numbers, seemed to pretty much show, what he was, or wasn't seeing, in the boats performance. |
Not sure what it can be.... yet..
Originally Posted by Black Baja
(Post 4483812)
Motor is still trying to go but can't. Usually means there is a restriction. When you do a pull and it drops of fast it means the motor is done.
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Ryan figured 30 hp for exhaust and sea pump, alternator... I don't have PS pump.
Originally Posted by donzi matt
(Post 4483814)
20/20 hindsight, taking the SM exhaust off and throwing dyno headers on would have been enlightening, and could have quantified what the exhaust is costing him power wise.
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very much considering M4 pro chargers, mild boost for now... 3-5lbs until I rid the TRS, try to be easy on it unless water is calm for WOT beatings, if I have to chop throttles forget it.. haha
Originally Posted by ICDEDPPL
(Post 4483811)
Blower motors.. you wanna go faster tomorrow just swap some pulleys, add a little jet ... boostane if you wanna get crazy or run some granny pulleys for everyday reliability.
http://www.birdsonggregory.com/wordp...ing_agency.jpg |
Originally Posted by Full Force
(Post 4483817)
Ryan figured 30 hp for exhaust and sea pump, alternator... I don't have PS pump.
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Originally Posted by Full Force
(Post 4483817)
Ryan figured 30 hp for exhaust and sea pump, alternator... I don't have PS pump.
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yes let me see if I have a still shot...to see..
Originally Posted by donzi matt
(Post 4483819)
I know, but one of your what ifs is if your exhaust is holding you back. Dyno headers might have quantified that. Did you guys happen to log vacuum on the dyno? That would tell you if your carbs are holding you back.
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true, I do know we checked WOT on mine.. lol
Originally Posted by MILD THUNDER
(Post 4483820)
We gotta stop "figuring" at some point. Ryans a buddy, but my first dyno pull, my engines made 650hp. I vomitted in my mouth a little bit. I insisted something was wrong. He was like "eh, my dyno's conservative, and its a 468" . I asked him to open the throttle all the way on the dyno console. Oops, throttle was only opening about 60%. Next pull, 761hp .
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1 Attachment(s)
If nothing else no matter what anyone thinks of me, I do however log more info them probably anyone lol
[ATTACH=CONFIG]559648[/ATTACH] |
Am I reading that right? Almost 2" vacuum at WOT?
If so, you got a restriction up top. |
Originally Posted by Black Baja
(Post 4483812)
Motor is still trying to go but can't. Usually means there is a restriction. When you do a pull and it drops of fast it means the motor is done.
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posted pic... from dyno.
Originally Posted by Gimme Fuel
(Post 4483827)
Yes. This. Manifold vacuum readings at WOT would be real easy to confirm this.
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seems that way, I thought we discussed it, and I also thought it was .4 or something, I was told .5 is ok... not sure where to look for a restriction.. ports lined up good, WOT is present.. I could see arrestor maybe on the boast but not on dyno...
Originally Posted by donzi matt
(Post 4483826)
Am I reading that right? Almost 2" vacuum at WOT?
If so, you got a restriction up top. |
Originally Posted by Full Force
(Post 4483829)
seems that way, I thought we discussed it, and I also thought it was .4 or something, I was told .5 is ok... not sure where to look for a restriction.. ports lined up good, WOT is present.. I could see arrestor maybe on the boast but not on dyno...
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I don't, not sure how I can fit them either under hatch ugh..
Originally Posted by donzi matt
(Post 4483830)
Got a buddy with a pair of dominators you can try?
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I was thinking just to see how the motor liked them. Just take the hatch off and let her eat.
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Dyno shows using 850 CFm, so I ruled out doms, figured at that point my 1050's were good hmm
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I can ask around and see ..
Originally Posted by donzi matt
(Post 4483836)
I was thinking just to see how the motor liked them. Just take the hatch off and let her eat.
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Originally Posted by Full Force
(Post 4483839)
I can ask around and see ..
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Originally Posted by Full Force
(Post 4483837)
Dyno shows using 850 CFm, so I ruled out doms, figured at that point my 1050's were good hmm
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Originally Posted by SB
(Post 4482782)
In response to post just above , hook vacuum gauge under carb and see what the vac is at WOT andtop rpm. This will tell you if carb is a decent restriction or not. Most carbs don't flow as advertised...just to add to confusion.
Originally Posted by donzi matt
(Post 4483819)
I know, but one of your what ifs is if your exhaust is holding you back. Dyno headers might have quantified that. Did you guys happen to log vacuum on the dyno? That would tell you if your carbs are holding you back.
Originally Posted by Gimme Fuel
(Post 4483827)
Yes. This. Manifold vacuum readings at WOT would be real easy to confirm this.
Originally Posted by donzi matt
(Post 4483840)
No matter what is going on with the cams, 1.7" vacuum at WOT is NFG and holding you back. I'd start with bigger carbs and see how it responds if it was me before trying anything else.
And that 1.7"HG on the dyno. In an enclosed engine compartment this # can get even worse. |
FF - just to make this part clear.
Again, 4bbl carb's are rated at 1.5"HG restriction. Your carb registered 1.7"HG. The dyno measured 850cfm. So, I hate to break it too you, if that dyno's airflow meter is correct,your carb is smaller than 850cfm.
Originally Posted by SB
(Post 4482782)
In response to post just above , hook vacuum gauge under carb and see what the vac is at WOT andtop rpm. This will tell you if carb is a decent restriction or not. Most carbs don't flow as advertised...just to add to confusion.
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Theres also more to it, than just a vacuum reading. Even IF you were to get it down to 0 vacuum, which is nearly impossible, it doesn't do any good, if the carb's not atomizing the fuel properly. You may actually see a LOSS in power.
This is why, slapping a 1050 dominator on a 330 merc engine, would produce unsatisfactory performance. Just because the manifold vacuum is very low, doesn't necessarily mean, more power. |
.75"HG to 1.1/1.2 "HG will typically be fine with carburetor metering.
Metering well under .75"HG usually requires a carb guy on his game. |
Originally Posted by MILD THUNDER
(Post 4483846)
Theres also more to it, than just a vacuum reading. Even IF you were to get it down to 0 vacuum, which is nearly impossible, it doesn't do any good, if the carb's not atomizing the fuel properly. You may actually see a LOSS in power.
This is why, slapping a 1050 dominator on a 330 merc engine, would produce unsatisfactory performance. Just because the manifold vacuum is very low, doesn't necessarily mean, more power. Look at bck's thread from a while back when he posted results for us on his 548? |
There is clearly a restriction in this combo and until it gets figured out then larger cam is useless. I'd bet less cam at this point would make more power. But sounds like he's off to a car project and wait til refresh.
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I would be willing to bet that cam with 305 or 315 cnc heads and 454 R intake and dominator would bring it to life.
Although yes I get it. Cam was spec'd for his parts. That obviously went wrong. |
Before we get too excited, anyone see my post earlier, about the throttle cable issue on the same dyno? That would certainly have an effect on tims dyno number if in fact, thats what was happening, but not in the boat. Throttle controls when using a servo, can fuk up. I like when some shops mount a camera above the throttle plates during a dyno pull, where you can see creep back.
A more common cause for both the low measured air flow and vacuum would be that the carburetor was not mechanically at WOT during the pull. Sometimes it is hard to get good carburetor travel with the available leverage and linkage. Older dyno's with the water piston used to creep all the time and loose the WOT during a test session, even the newer ones with servo or cable linkages can creep or loose the WOT capability. |
I was pro 4500 dominator on this build from the get go, so don't get me wrong. I'd still like to see a dominator on it.
Tim, mount a vacuum gauge on it in the boat. See what you have. Then try the flame arrestors off. See what you have. Then crack the hatch open, and see what you have. This would be alot easier if you had daytona sensors boxes using a map sensor, and data logging this stuff. |
Tim- what are you using for arrestors? I was loosing 3-4 mph with HP 500 arrestors compared to no arrestors on my 650 hp 509's. Like mild said above, if you haven't tried running it without them on do it. If you gain- you know that's at least part of your issue and a easy fix. I ended up going to 10X5 gaffrigs and that problem is now solved.
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