5.3 s475 slow spool
Reminds me of the time I first drove my uncle's high stall Firebird as a kid. There was ice on the road and I had never driven a car with a tach before. I mistook the tach for the speedometer and since I heard the engine revving up I thought it was slipping on the ice. You are not going to build much boost at part throttle and as someone has said, why would you want to. As far as feeling "laggy" below the stall speed? Who could have guessed that was going to happen or better yet what it even means?
Guess I just don't see how the car can NOT feel laggy while the converter is not coupled, although the OP did indicate a possible issue with the converter plus its a B&M converter which I've never been impressed with their products.
I think we'd all agree that a converter is one of those parts that really shines when its spec'd exactly for combo instead of ordered from Jegs for a variety of applications.
Thread Starter
Teching In
Joined: Aug 2021
Posts: 8
Likes: 3
Yeah convertor I think is the issue. It worked good on another setup before
me so, we shall see what the verdict is it deff wasn’t couplin on the big end. On dyno it is still trying to catch up at 6500. Might even get it restalled shop here locally is really good
me so, we shall see what the verdict is it deff wasn’t couplin on the big end. On dyno it is still trying to catch up at 6500. Might even get it restalled shop here locally is really good
I switched from a brand name converter to a custom spec'd Continental Converter in my nitrous BBC Camaro and it completely changed the car.
The brands mentioned before use better components and have knowledge from the racing industry to engineer some of the best converters on the market.
Circle D is one and PTC is another that come highly recommended from guys that go way faster than we'll probably ever go. ; )
If you're using HP Tuners or Holley you can monitor converter slip which would help you identify any potential issues, each converter is different so you'd want to ask the manufacturer what the acceptable amount of slip is, another advantage to working with the companies mentioned before, not sure how B&M would be to work with.
Hey guys new here been dealing with my car for last few years with different setups. Car is a 85 iroc 5.3 aluminum block, s475, Bosch 1000, dual fuel pumps, terminator x, th400 3500stall, Chinese 44mm wastegate, sloppy stage 2 cam and flow sheet metal intake. When out cruising or on dyno car is really sluggish to come
up on boost lazy from that 1200-3200 range. Once it lights it’s makes decent power . But is extremely laggy any ideas on what could be causing this?. Second setup and still same thing .
up on boost lazy from that 1200-3200 range. Once it lights it’s makes decent power . But is extremely laggy any ideas on what could be causing this?. Second setup and still same thing .
From the cubes/compression vs. turbo size to the stall to the sheet metal intake, you have built the exact wrong setup if you're wanting off idle boost and part throttle positive pressure. A stall isn't going to fix that unless you're not serious with your goals. I'm probably the most picky person in this thread for boost threshold and how responsive I want a turbo setup and I would have done the exact opposite. Cubes and compression, a smaller turbo, stock intake manifold/truck intake if possible, and a low stall, preferably a stick.
I was talking to a guy with a 5.3 with a pair of S366 and after optimizing the combo with stall speed, intake, cam, he got tired of waiting 2-3 seconds to build boost when going up against super charged cars on the street.
He upgraded to a 427 with twins and said that building boost now is a night and day difference and the 427 is so much more fun on the street. It seems like these boosted 5.3 OEM blocks can only take us so far on the street, and then it comes time to having to get the aftermarket block to run the larger stroke and enjoy the extra cubes on the street.
He upgraded to a 427 with twins and said that building boost now is a night and day difference and the 427 is so much more fun on the street. It seems like these boosted 5.3 OEM blocks can only take us so far on the street, and then it comes time to having to get the aftermarket block to run the larger stroke and enjoy the extra cubes on the street.
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Verdad Gallardo I was talking to a guy with a 5.3 with a pair of S366 and after optimizing the combo with stall speed, intake, cam, he got tired of waiting 2-3 seconds to build boost when going up against super charged cars on the street.
He upgraded to a 427 with twins and said that building boost now is a night and day difference and the 427 is so much more fun on the street. It seems like these boosted 5.3 OEM blocks can only take us so far on the street, and then it comes time to having to get the aftermarket block to run the larger stroke and enjoy the extra cubes on the street.
He upgraded to a 427 with twins and said that building boost now is a night and day difference and the 427 is so much more fun on the street. It seems like these boosted 5.3 OEM blocks can only take us so far on the street, and then it comes time to having to get the aftermarket block to run the larger stroke and enjoy the extra cubes on the street.
What turbo specs for 5.3 would you recommend for making 1250hp at the track on E85 and also have it be a fun street car where it doesn't take 2-3 seconds to build boost. (if possible)?
Give them a call and run down your combo and they'll set you up, I'd say call PTC but I did and they never got back to me to I went with Circle D and the support is excellent.
On another note, my S484 doesn't spool slow, in fact it spools faster than my old T7875 did, different combo but you get the point. ; )
A few chunks in that converter.
Which is a budget nitrous piece, rated to 650 hp. Which you will exceed with ease.
I wouldn’t hesitate to call PTC. Give them your combo, be honest about goals, rpm etc and they will likely nail it on the first try.
Maybe have the B&M fixed for use in another project.
Would also be interesting to know the specs on the S475. There are a few variations on the exhaust side.
BTW, these setups aren’t going to make boost below stall speed. Unless it’s on the 2 step.
Detuning to run 91 octane isn’t helping either.
Ron
Which is a budget nitrous piece, rated to 650 hp. Which you will exceed with ease.
I wouldn’t hesitate to call PTC. Give them your combo, be honest about goals, rpm etc and they will likely nail it on the first try.
Maybe have the B&M fixed for use in another project.
Would also be interesting to know the specs on the S475. There are a few variations on the exhaust side.
BTW, these setups aren’t going to make boost below stall speed. Unless it’s on the 2 step.
Detuning to run 91 octane isn’t helping either.
Ron
Last edited by RonSSNova; Aug 5, 2021 at 11:16 AM.
I believe these were a pair of 66/73 T4 with 0.81 AR which made 1250hp at 35 PSI. So he was trying to make high power at the track on high boost while still trying to use this 5.3 car for street duty. Upgrading to the 427 with properly sized turbos fixed his issue enabling him to make that 1250 hp off lower boost while also being more fun on the street due to the better response time.
What turbo specs for 5.3 would you recommend for making 1250hp at the track on E85 and also have it be a fun street car where it doesn't take 2-3 seconds to build boost. (if possible)?
What turbo specs for 5.3 would you recommend for making 1250hp at the track on E85 and also have it be a fun street car where it doesn't take 2-3 seconds to build boost. (if possible)?
I follow. I should have been more clear about his hp goals at the track in my initial post. If it was just a dedicated track car, I would have told him to just boost a SBE 5.3 until it blows at the track and then pop another one in lol.
Thread Starter
Teching In
Joined: Aug 2021
Posts: 8
Likes: 3
Cheap *** B&M, the Circle D LS Pro Series Billet was around $800 for my TH400 and will handle 1000whp.
Give them a call and run down your combo and they'll set you up, I'd say call PTC but I did and they never got back to me to I went with Circle D and the support is excellent.
On another note, my S484 doesn't spool slow, in fact it spools faster than my old T7875 did, different combo but you get the point. ; )
Give them a call and run down your combo and they'll set you up, I'd say call PTC but I did and they never got back to me to I went with Circle D and the support is excellent.
On another note, my S484 doesn't spool slow, in fact it spools faster than my old T7875 did, different combo but you get the point. ; )
yeah got circle d with a specd unit 1100 cnd before shipping and three week wait lmao seems like I’m gonna do it
Guarantee you'll be floored how big a difference the new converter will make.
Teching In
Joined: Sep 2018
Posts: 6
Likes: 0
5.7 ls1 spooling I'm really interested in getting your guys opinions on my situation.
LS1
fast 102 tb&intake
114lb injectors
E85
VSR Gen 3 billet 7875 1.25 A/R
M6 car
Doesn't start to spool till about 4100 and doesn't light off good till 4500.
Cam is 228/232 .600 .600 114LSA 111ICL
Is the A/R just too big or could a different cam maybe get it spooling sooner?
It makes great power I would just like it to come on sooner if possible. Definitely not peak any sooner either
777 rwhp @ 12.5 psi @ 5960rpm
700 lb ft. @ 5430rpm
I can post my dyno sheet and video if that helps.
Thanks.
LS1
fast 102 tb&intake
114lb injectors
E85
VSR Gen 3 billet 7875 1.25 A/R
M6 car
Doesn't start to spool till about 4100 and doesn't light off good till 4500.
Cam is 228/232 .600 .600 114LSA 111ICL
Is the A/R just too big or could a different cam maybe get it spooling sooner?
It makes great power I would just like it to come on sooner if possible. Definitely not peak any sooner either
777 rwhp @ 12.5 psi @ 5960rpm
700 lb ft. @ 5430rpm
I can post my dyno sheet and video if that helps.
Thanks.
I'm really interested in getting your guys opinions on my situation.
LS1
fast 102 tb&intake
114lb injectors
E85
VSR Gen 3 billet 7875 1.25 A/R
M6 car
Doesn't start to spool till about 4100 and doesn't light off good till 4500.
Cam is 228/232 .600 .600 114LSA 111ICL
Is the A/R just too big or could a different cam maybe get it spooling sooner?
It makes great power I would just like it to come on sooner if possible. Definitely not peak any sooner either
777 rwhp @ 12.5 psi @ 5960rpm
700 lb ft. @ 5430rpm
I can post my dyno sheet and video if that helps.
Thanks.
LS1
fast 102 tb&intake
114lb injectors
E85
VSR Gen 3 billet 7875 1.25 A/R
M6 car
Doesn't start to spool till about 4100 and doesn't light off good till 4500.
Cam is 228/232 .600 .600 114LSA 111ICL
Is the A/R just too big or could a different cam maybe get it spooling sooner?
It makes great power I would just like it to come on sooner if possible. Definitely not peak any sooner either
777 rwhp @ 12.5 psi @ 5960rpm
700 lb ft. @ 5430rpm
I can post my dyno sheet and video if that helps.
Thanks.
Teching In
Joined: Sep 2018
Posts: 6
Likes: 0
Once mine spools it hits insanely hard, I just felt like 4500 rpm was a little late.