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Here a fresh dyno sheet . Overall pretty happy with the results . I knew we would run into issues. Nothing big so far
15 psi dropping to 10psi at 5000rpm Looks promising so far. Ran into injector scaling issues . Hoping to be back on the rollers this week . tuner wants fresh plugs before we
push for any more
this is on pump fuel 91 oct and 100%meth .timing was also conservative @ 14 degrees
How the 96mm turbine work for the S480 for daily street driving?
Curious on how quick the turbo starts to spool at?
I've used the S478 and S480 83/96 turbine wheels on diesel trucks before. I want to put on in my 85 vette, once I get a motor built up.
i have not driven it on the street yet. it looks like a very its responsive on the dyno we saw full boost at 3500 rpm. im thinking it should be fine . with 3000rpm plus of full boost
Back from the dyno with new plugs
Good news and bad news. Bad news we still have a misfire when we hit boost
Good news is @10psi we are at 780whp .last time we where making 745whp @10psi )
Going again tomorrow with new msd plug wires and another set of coil packs.
Back from the dyno with new plugs
Good news and bad news. Bad news we still have a misfire when we hit boost
Good news is @10psi we are at 780whp .last time we where making 745whp @10psi )
Going again tomorrow with new msd plug wires and another set of coil packs.
I had a similar issue before with two of my MSD plug wires that had high ohms of resistance causing a misfire under boost. What plugs are you running and gap? That thing is making some jam for sure. Congrats and hope you get it figured out.
I had a similar issue before with two of my MSD plug wires that had high ohms of resistance causing a misfire under boost. What plugs are you running and gap? That thing is making some jam for sure. Congrats and hope you get it figured out.
Running some Tr6s gapped to 25
With ac Delco wires .if the plugs and coils don't work will try 20 on the gap Only reason I'm trying the msd wires is cause they are new and free to try out lol .I like the oem stuff myself
Back from the dyno again lol
After putting new plug, new wires
,different coils. We still hit a wall at 860-870whp 13.5psi-14psi. Me and my tuner came to the conclusion my exhaust is causing too much back pressure . I'm running a 4 inch to two 2.5 inch to my 2.5 borla exhaust (I know this whole system sucks lol)
Anyways I'll be back Monday night hopefully. Getting a 5 inch down pipe fabbed up ( 90 bend out of the turbo).since I have no hood right now it's will be easy to try it and cost under $100 . This way I'll know if this is the issue. It's the only thing that makes sense to us .
Back from the dyno again lol
After putting new plug, new wires
,different coils. We still hit a wall at 860-870whp 13.5psi-14psi. Me and my tuner came to the conclusion my exhaust is causing too much back pressure . I'm running a 4 inch to two 2.5 inch to my 2.5 borla exhaust (I know this whole system sucks lol)
.
I decided to go 4 inch off the turbo into a Y just before the differential then duel 3 inch over the axles and to the bumper . It sounds decent. If your curious, shoot me a text one day and I'll send you a clip of it idling. I think the fuel pump is louder than the exhaust. 708-935-2571
I went back to the beginning of the thread and saw that you mentioned a custom turbo cam. What are the details on the rest of the valvetrain? Lift, springs, pushrods, rocker arms, preload, etc?
I went back to the beginning of the thread and saw that you mentioned a custom turbo cam. What are the details on the rest of the valvetrain? Lift, springs, pushrods, rocker arms, preload, etc?
CAM is
118 lsa
240 238
658 642
comp dual valve springs
LS7 rockers with BTR trunion upgrade
not sure wich pushrods tough
lots of people are telling my its valve springs
or lifters
i just find it very weird that the car runs good at 10psi made still respectable power 790whp 820trq
I'm still trying to figure out your induction parts. I think you stated earlier that you have an LS7 engine, edelbrock cnc heads, ls6 intake and ls7 rocker arms?
I'm trying to figure out how all of those match up. Not saying it doesn't work, I've just never seen this combo or not familiar with edelbrock's head offerings that are cathedral port but work with LS7 rockers.
As far as things being ok on 10 psi but then having issues: If the valvetrain is marginal, it can get worse as the boost increases. Do you know the open and closed pressure on the valve springs, what their installed height is, and where the coil bind limit is?
0.658" lift seems a little strong in a boosted application with stainless valves and hydraulic roller lifters. Once again, people have made it work, but it requires certain supporting parts and a more detailed valvetrain setup.
I'm still trying to figure out your induction parts. I think you stated earlier that you have an LS7 engine, edelbrock cnc heads, ls6 intake and ls7 rocker arms?
I'm trying to figure out how all of those match up. Not saying it doesn't work, I've just never seen this combo or not familiar with edelbrock's head offerings that are cathedral port but work with LS7 rockers.
As far as things being ok on 10 psi but then having issues: If the valvetrain is marginal, it can get worse as the boost increases. Do you know the open and closed pressure on the valve springs, what their installed height is, and where the coil bind limit is?
0.658" lift seems a little strong in a boosted application with stainless valves and hydraulic roller lifters. Once again, people have made it work, but it requires certain supporting parts and a more detailed valvetrain setup.
This engine was originally built by A&A for a YSI setup. The valve Springs are probably the original that they would have installed .I just spoke with my engine builder I'm going to bite the bullet and order some new Springs. Any recommendations? Anything else I should change up while it's apart.?
From my understanding the cam was a mild cam . Kinda sucks cause I tough everything was really good in the engine. Turns out its just OK parts lol
04-05-2016, 08:44 AM
nah great job
)
