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SB 03-31-2017 11:49 AM

Don't worry about it, I assumed you meant there was one recently. I followed the 1st one when it went down.

Tibbstoy2 03-31-2017 12:59 PM

Mild Thunder - thanks for the links for the single carb intake induction and prosystems post, very interesting.

Rob - Cool build! Looking forward to seeing how this one turns out - especially if you compare a 4150 carb to a dominator on the dyno.

I'm going to try 2200 CFM throttle bodies with an HVH style 4500->4150 modified spacer on my Brodix HVH 4150 intakes vs. my current 1000 Holley TB's. Similar to Smitty's testing, but I don't have the dominator intake... which may help my flow velocity. I'm not pulling engines, but I do plan to do as close to back to back water tests as possible. I only question whether 2200 is WAY too much throttle plate, but according to Prosystems - maybe not.

articfriends 03-31-2017 02:42 PM


Originally Posted by Tibbstoy2 (Post 4542504)
Mild Thunder - thanks for the links for the single carb intake induction and prosystems post, very interesting.

Rob - Cool build! Looking forward to seeing how this one turns out - especially if you compare a 4150 carb to a dominator on the dyno.

I'm going to try 2200 CFM throttle bodies with an HVH style 4500->4150 modified spacer on my Brodix HVH 4150 intakes vs. my current 1000 Holley TB's. Similar to Smitty's testing, but I don't have the dominator intake... which may help my flow velocity. I'm not pulling engines, but I do plan to do as close to back to back water tests as possible. I only question whether 2200 is WAY too much throttle plate, but according to Prosystems - maybe not.

Well, again, AFTER tayloring timing curve and tweaking afrs I was able to gain 10-12 solid hp at wot over the best carb I dynoed with BUT I also found that last 10 hp by pulling 1 to 2 degrees of timing out on top past my highest amount so carb might have done that if it had a timing table like a efi does, I was able to beat my best corrected and observed tq by about 4-5 ft lbs but I still havent found the 20+ ft lbs I lost down low from 3000-4600. I did some steady state testing at 4400 wondering IF giving tb less than wot would bring back tq, it did not. Testing with a single blade TB thats supposed to flow slightly less tomorrow, would really like to test with a 1600 cfm TB to see if that torque would come back or if carb simply worked better at those rpms, going to be intersteing to hear what YOU find, Smitty
EZ striper also said they had idle issues with the 2200 when they ran one, I havent worried abput idle yet on dyno

Tibbstoy2 03-31-2017 03:15 PM


Originally Posted by articfriends (Post 4542536)
Well, again, AFTER tayloring timing curve and tweaking afrs I was able to gain 10-12 solid hp at wot over the best carb I dynoed with BUT I also found that last 10 hp by pulling 1 to 2 degrees of timing out on top past my highest amount so carb might have done that if it had a timing table like a efi does, I was able to beat my best corrected and observed tq by about 4-5 ft lbs but I still havent found the 20+ ft lbs I lost down low from 3000-4600. I did some steady state testing at 4400 wondering IF giving tb less than wot would bring back tq, it did not. Testing with a single blade TB thats supposed to flow slightly less tomorrow, would really like to test with a 1600 cfm TB to see if that torque would come back or if carb simply worked better at those rpms, going to be intersteing to hear what YOU find, Smitty
EZ striper also said they had idle issues with the 2200 when they ran one, I havent worried abput idle yet on dyno

Thanks for the testing information, Smitty. I'm watching your thread closely and really appreciate what you're doing. It would be very interesting to put a 1500-1600 TB on it to see if it is a carb/fuel temperature or atomization issue.

How much are the injectors tipped (if any) on your dominator intake? I've been told that getting them to fire as much as possible at the back of the intake valve is a must to avoid spraying the runner wall like some of the aftermarket package deal offerings are.

Here is what I ended up doing with Brodix 4150 intake (basically did it to figure how I needed to machine my intakes and fuel rails):
https://lh3.googleusercontent.com/-i...2Bassembly.jpg

https://lh3.googleusercontent.com/-1...keassembly.JPG

Based on this, I found I could get 14 degrees of tilt on mine and still be able to install the rails:
https://lh3.googleusercontent.com/-B...ont%2Bview.jpg

I'm trying to get out in front of the idle issues with the 2200... KVOGT on here got his blower motors with dual 2100's to work with Holley EFI nicely. I'm going to try the same alpha-N idle/speed density cruise to top end combo strategy he's using out of the gate... Even if it does auto-tune properly, it gives me a lot of table resolution to really focus on the tip-in event on those big throttle blades.

Rookie 03-31-2017 09:30 PM


Originally Posted by rob vanharten (Post 4542255)
Smitty, that is very generous!! My new Holley 1050's literally just showed up today...Are you offering a dyno service? I am also having Jim doing these custom 4150-4500 adapters. I feel like I am to far along to switch up now but they sound like they rock!!! I read your 548 post and they sure proved themselves there!! Can you let me know on dyno and carb pricing??

Rob, when do you plan on completing and dynoing? I need to finish the cad on the adapters.

articfriends 03-31-2017 09:41 PM


Originally Posted by Tibbstoy2 (Post 4542542)
Thanks for the testing information, Smitty. I'm watching your thread closely and really appreciate what you're doing. It would be very interesting to put a 1500-1600 TB on it to see if it is a carb/fuel temperature or atomization issue.

How much are the injectors tipped (if any) on your dominator intake? I've been told that getting them to fire as much as possible at the back of the intake valve is a must to avoid spraying the runner wall like some of the aftermarket package deal offerings are.

Here is what I ended up doing with Brodix 4150 intake (basically did it to figure how I needed to machine my intakes and fuel rails):
https://lh3.googleusercontent.com/-i...2Bassembly.jpg

https://lh3.googleusercontent.com/-1...keassembly.JPG

Based on this, I found I could get 14 degrees of tilt on mine and still be able to install the rails:
https://lh3.googleusercontent.com/-B...ont%2Bview.jpg

I'm trying to get out in front of the idle issues with the 2200... KVOGT on here got his blower motors with dual 2100's to work with Holley EFI nicely. I'm going to try the same alpha-N idle/speed density cruise to top end combo strategy he's using out of the gate... Even if it does auto-tune properly, it gives me a lot of table resolution to really focus on the tip-in event on those big throttle blades.

I love that tip in on your injectors, great engineering. I really didnt give it that much thought but am now that im seeing these low tq numbers not quite where they were carbed. Im going to try a few fuel changes on dyno tomm and pull from 2800 to 4600 and see if theres anything more to be found, norms theory almost completely agrees with your tipped injector angle, he feels my injectors may be spraying fuel acrossed the air path in the port, causing a curtaining effect and that maybe at higher rpms/velocitys it has enough airflow to negate it, we'll see, nice work though on that angle, i may do same thing on my final intake i run, Smitty

rob vanharten 03-31-2017 09:55 PM


Originally Posted by Rookie (Post 4542642)
Rob, when do you plan on completing and dynoing? I need to finish the cad on the adapters.

My goal would be to have these motors wrapped up and on the dyno by early May

GPM 04-01-2017 08:03 AM

Smitty, have you tried firing the injectors at different degrees before and after TDC to see where they are most efficient for your motor ?

articfriends 04-01-2017 09:01 AM


Originally Posted by GPM (Post 4542724)
Smitty, have you tried firing the injectors at different degrees before and after TDC to see where they are most efficient for your motor ?

No as i am batch firing them, i will say this though, the last motor i dynoed, a 550hp 502 mpi, it made zero difference in hp /tq ANYWHERE when i switched batches opposite of what they are supposed to be, found same result running one batch down even side of motor and one batch down odd side, fwiw, Smitty

MILD THUNDER 04-01-2017 09:15 AM

It be interesting to see what happens to the bsfc , with changing injector timing. I assume the camshaft events can dictate a need for a change in injector timing? Id think that if the injector timing was based on say a stock cam, and you go to a bigger cam, that opens the exhaust valve sooner, and had more overlap, maybe firing the injector later, so that you arent blowing fuel out the exhaust?

Maybe not much power to be gained here, but maybe some fuel efficiency? Just thinking out my azz on this


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