Holley jets.....how many ## increase at a time
07-20-2007, 10:26 AM
#11
Registered
iTrader: (1)
Make sure your fuel pump vent tube goes to blue arrow in this pic. If you hook it up to a vacuum source it will reduce pump psi. Make sure their is a vaccum plug over the pcv nipple.
Run on can be also caused by too high of an idle, fuel dripping out of boosters during idle (check float level and/or fuel psi and/or idle throttle angle) .
=====================
For my knowledge,
I only know of one cast iron quadrajet intake manifold for Vortec heads and it is aftmarket with GM #s on it but is not GM. Made for rules racing, even though it is horrible in terms of performance.
Do you have an aluminum intake from Volvo ? Or do they actually make a cast iron 4bbl intake that I'm not aware of ?
Run on can be also caused by too high of an idle, fuel dripping out of boosters during idle (check float level and/or fuel psi and/or idle throttle angle) .
=====================
For my knowledge,
I only know of one cast iron quadrajet intake manifold for Vortec heads and it is aftmarket with GM #s on it but is not GM. Made for rules racing, even though it is horrible in terms of performance.
Do you have an aluminum intake from Volvo ? Or do they actually make a cast iron 4bbl intake that I'm not aware of ?
Last edited by SB; 10-14-2011 at 07:00 PM.
07-20-2007, 04:17 PM
#12
Registered
Thread Starter
Join Date: Jan 2004
Location: Saint Petersburg Fl
Posts: 1,571
Likes: 0
Received 0 Likes
on
0 Posts
The intake is OEM and is aluminum.......I think it is aluminum, now not 100% I will have to look. It has VP numbers stamped on it for sure. The vent hose you point to is actually capped (have an electric fuel pump. PVC nipple in the base (rear) is actually hooked to a PVC valve.
Intresting about the BG carb. The spacer has me wondering, the factory intake is wide open sort of oblong because of the different diameter butterflies. I have no spacer and wondered about the transition between the carb and intake with no plenum effect. I wonder what Volvo does with their 5.7 setup. I have a friend with that motor and I will look at his boat or maybe online I can see in schematic. .
Intresting about the BG carb. The spacer has me wondering, the factory intake is wide open sort of oblong because of the different diameter butterflies. I have no spacer and wondered about the transition between the carb and intake with no plenum effect. I wonder what Volvo does with their 5.7 setup. I have a friend with that motor and I will look at his boat or maybe online I can see in schematic. .
07-20-2007, 05:20 PM
#13
Banned
Join Date: Sep 2001
Location: Deland, Florida
Posts: 25,191
Likes: 0
Received 0 Likes
on
0 Posts
Mike, there is a carb place on the corner of 49th Street and 118th Avenue that has done work on marine carbs for me. I think a four barrel rebuild cost me about $100, and I had it back the next day. I can't remember the name of the business.
If the business isn't there anymore, stop by Ray Hanke's shop, and ask him who does his carb work. He's right there near that place on 49th. I can't remember if Force 10 (Ray's shop) is north or south of 118th.
If the business isn't there anymore, stop by Ray Hanke's shop, and ask him who does his carb work. He's right there near that place on 49th. I can't remember if Force 10 (Ray's shop) is north or south of 118th.
Last edited by cuda; 07-20-2007 at 05:23 PM.
07-20-2007, 09:19 PM
#14
Registered
Thread Starter
Join Date: Jan 2004
Location: Saint Petersburg Fl
Posts: 1,571
Likes: 0
Received 0 Likes
on
0 Posts
The carb place on 49th is superior I think. Good to know they did good work for someone. thanks.
Raggededge might be on to something, I looked up the 5.7 VP and it looks like from the schematic they use a spacer plate under the carb. Interesting, might be same situation he ran into with BG stuff. It is only like 40 dollars so I think i will buy one and try that. Boat are fun. :-)
Raggededge might be on to something, I looked up the 5.7 VP and it looks like from the schematic they use a spacer plate under the carb. Interesting, might be same situation he ran into with BG stuff. It is only like 40 dollars so I think i will buy one and try that. Boat are fun. :-)
07-20-2007, 09:41 PM
#15
Banned
Join Date: Sep 2001
Location: Deland, Florida
Posts: 25,191
Likes: 0
Received 0 Likes
on
0 Posts
08-24-2007, 10:07 AM
#16
Registered
Thread Starter
Join Date: Jan 2004
Location: Saint Petersburg Fl
Posts: 1,571
Likes: 0
Received 0 Likes
on
0 Posts
I sent the carb back to Holley for their "flow and repair" service. I just heard from them and they said they put it on the flow bench and it flows fine......WTF. They claim it could be a fuel pressure and/or timing issue but boat runs perfect with old carb initially and after I re-installed it to send the new carb back to Holley. I looked a a factory 5.7 setup that uses same carb and manifold and no spacer plate. I am lost......any thoughts?
08-31-2007, 07:35 AM
#17
Registered
Thread Starter
Join Date: Jan 2004
Location: Saint Petersburg Fl
Posts: 1,571
Likes: 0
Received 0 Likes
on
0 Posts
Jetting/Carb Update..and more confusion ??
I have the carb back with the flow spec sheet from Holley, sure enough it looks good. So I got to thinking, I never did the exact same test (3000 rpm cruise and quick shut down plug reading ) with old factory /stock 2 barrel so I did that last night. Guess what, dieseled a and the plug was clean white and looked new (was not) . WTF, I am really lost. Could it really be too lean and still basically run OK and not blown up by now? Am I an idiot and forgot how to read plugs. Could it be the fuel I am using does not color plugs. (gas station 87 octane) I am 99% sure plugs are right heat range , it is all stock but I will verify I have not been putting wrong plugs in forever since I bought boat used like 4 yrs ago and always just replaced them with what I removed.
Oh I have not made a fuel pressure test rig yet but it has electric pump and if the fuel flow was an issue wouldn't it show up more at WOT (run bowls dry) ?
Oh I have not made a fuel pressure test rig yet but it has electric pump and if the fuel flow was an issue wouldn't it show up more at WOT (run bowls dry) ?
Last edited by happy hours; 08-31-2007 at 07:38 AM.
08-31-2007, 09:15 AM
#18
Registered
iTrader: (1)
By notes ( you should always check to make sure)
Vortec head ( Vortec's have 4 intake bolts per side) marine sbc's use Champion RS12YC / Delco MR43LTS / or equivalent. These are 14mm x .708 thread and tapered seat.
The earlier heads (6 intake bolts per side) use a 14mm x .460"long thread and tapered seat . Such as Champion RV8C, RV91MC (projected), or Delco MR43T , MR 43TS (projected), or equivalent.
==========================
Are you sure you are doing the timing right ? I am not experienced with Volvo's, but other systems are convential and some aren't where they need specific procedures to set timing.
Vortec head ( Vortec's have 4 intake bolts per side) marine sbc's use Champion RS12YC / Delco MR43LTS / or equivalent. These are 14mm x .708 thread and tapered seat.
The earlier heads (6 intake bolts per side) use a 14mm x .460"long thread and tapered seat . Such as Champion RV8C, RV91MC (projected), or Delco MR43T , MR 43TS (projected), or equivalent.
==========================
Are you sure you are doing the timing right ? I am not experienced with Volvo's, but other systems are convential and some aren't where they need specific procedures to set timing.
08-31-2007, 09:22 AM
#19
Registered
Thread Starter
Join Date: Jan 2004
Location: Saint Petersburg Fl
Posts: 1,571
Likes: 0
Received 0 Likes
on
0 Posts
I am at work so going by memory but I believe I have Champion RS12Y, so I have the right plugs. (motor has Vortex heads)
The timing is typical mechanical advance so nothing to short to ground like MC system. The initial timing is 6 BTDC and stops follows the curve per the factory manual , although it does fall slightly short in total advance (stops around 22 BTDC and manual says it should goto 26-28. Since that all happens at > 3200 RPM I am pretty sure not causing my issue. Correct?
The timing is typical mechanical advance so nothing to short to ground like MC system. The initial timing is 6 BTDC and stops follows the curve per the factory manual , although it does fall slightly short in total advance (stops around 22 BTDC and manual says it should goto 26-28. Since that all happens at > 3200 RPM I am pretty sure not causing my issue. Correct?
By notes ( you should always check to make sure)
Vortec head ( Vortec's have 4 intake bolts per side) marine sbc's use Champion RS12YC / Delco MR43LTS / or equivalent. These are 14mm x .708 thread and tapered seat.
The earlier heads (6 intake bolts per side) use a 14mm x .460"long thread and tapered seat . Such as Champion RV8C, RV91MC (projected), or Delco MR43T , MR 43TS (projected), or equivalent.
==========================
Are you sure you are doing the timing right ? I am not experienced with Volvo's, but other systems are convential and some aren't where they need specific procedures to set timing.
Vortec head ( Vortec's have 4 intake bolts per side) marine sbc's use Champion RS12YC / Delco MR43LTS / or equivalent. These are 14mm x .708 thread and tapered seat.
The earlier heads (6 intake bolts per side) use a 14mm x .460"long thread and tapered seat . Such as Champion RV8C, RV91MC (projected), or Delco MR43T , MR 43TS (projected), or equivalent.
==========================
Are you sure you are doing the timing right ? I am not experienced with Volvo's, but other systems are convential and some aren't where they need specific procedures to set timing.
Last edited by happy hours; 08-31-2007 at 09:32 AM.
09-01-2007, 04:39 PM
#20
Registered
Thread Starter
Join Date: Jan 2004
Location: Saint Petersburg Fl
Posts: 1,571
Likes: 0
Received 0 Likes
on
0 Posts
I checked the plugs today and as I expected the plug is dark brown and looks like it does every time I have ever changed them in the past . No-wake zone back to ramp and then flushing (salt water bpat) so it has idled a while. It is Champion RS12YC so it is right heat range. Thoughts?
