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samwint77 01-10-2019 05:51 PM

Can you give me a WHP prediction with this combo?
 
Grandsport A8 bone stock baselined at 371 / 389. I'm adding a maggy with the 3" pulley, texas speedway long tube headers and x pipe without cats, lt4 fuel pump and injectors, and a voltage booster for the low side.

I'll post the number when it gets out and see whos closest. lol

hogurt 01-10-2019 07:48 PM


Originally Posted by samwint77 (Post 1598660460)
Grandsport A8 bone stock baselined at 371 / 389. I'm adding a maggy with the 3" pulley, texas speedway long tube headers and x pipe without cats, lt4 fuel pump and injectors, and a voltage booster for the low side.

I'll post the number when it gets out and see whos closest. lol

Are you thinking about the 75mm pulley with the Maggie? Do you have forged internals? Are you planning to add the cam with a larger fuel lobe at the same time? Are you adding e85 or alky injection?

When you say you are adding the LT4 fuel pump, are you saying the high pressure pump or the low pressure in-tank pump?

samwint77 01-10-2019 10:05 PM


Originally Posted by hogurt (Post 1598661224)

Are you thinking about the 75mm pulley with the Maggie? Do you have forged internals? Are you planning to add the cam with a larger fuel lobe at the same time? Are you adding e85 or alky injection?

When you say you are adding the LT4 fuel pump, are you saying the high pressure pump or the low pressure in-tank pump?

I believe its the 80mm. Internals are stock. Cam will be done in the 2nd phase when I change the pistons. I'm going to add e85 around march and a throttle body to probably.

hogurt 01-11-2019 12:43 AM


Originally Posted by samwint77 (Post 1598661952)
I believe its the 80mm. Internals are stock. Cam will be done in the 2nd phase when I change the pistons. I'm going to add e85 around march and a throttle body to probably.

Doing a little math::
98mm @5psi 540whp
95mm @7psi 570whp (LT1 fuel limit)
90mm @9 psi 600whp
85mm @11psi 630whp
80mm @13psi 660whp (93 octane limit)
75mm @15psi 690whp
70mm @17psi 720whp

So, you will likely be between 630-660whp and you will be at the 93 octane limit.

Once you add a cam with e85 it really changes things. As an example, you could run just over 700whp with e85 @8psi (on the 85mm pulley). It's awesome! Less effort, stress on the car and bam, great results.
It looks a little different and obviously the cam profile matters. I went with the Jannetty Racing - JRE Super Street Brawler package (and went forged).
85mm 8psi with e85 pump (e70) - 715whp
80mm 10psi 745whp
75mm 12psi - 776whp
70mm 14psi - out of fuel injector on e70. . .and ran out of time to continue tuning because of the weather.
We will do some tweaking when the weather gets nice again and we will likely be in the 820-850whp range running 14-15psi. I haven't decided on my path to address injector (bigger injectors, race fuel, alky injection).

All I can say is this, get ready for some new rubber because this journey, my friend, ends up with a seriously beastly ride. Looking forward to your progress. Can't wait to watch.

samwint77 01-11-2019 08:10 AM


Originally Posted by hogurt (Post 1598662531)
Doing a little math::
98mm @5psi 540whp
95mm @7psi 570whp (LT1 fuel limit)
90mm @9 psi 600whp
85mm @11psi 630whp
80mm @13psi 660whp (93 octane limit)
75mm @15psi 690whp
70mm @17psi 720whp

So, you will likely be between 630-660whp and you will be at the 93 octane limit.

Once you add a cam with e85 it really changes things. As an example, you could run just over 700whp with e85 @8psi (on the 85mm pulley). It's awesome! Less effort, stress on the car and bam, great results.
It looks a little different and obviously the cam profile matters. I went with the Jannetty Racing - JRE Super Street Brawler package (and went forged).
85mm 8psi with e85 pump (e70) - 715whp
80mm 10psi 745whp
75mm 12psi - 776whp
70mm 14psi - out of fuel injector on e70. . .and ran out of time to continue tuning because of the weather.
We will do some tweaking when the weather gets nice again and we will likely be in the 820-850whp range running 14-15psi. I haven't decided on my path to address injector (bigger injectors, race fuel, alky injection).

All I can say is this, get ready for some new rubber because this journey, my friend, ends up with a seriously beastly ride. Looking forward to your progress. Can't wait to watch.

Wow, that makes me a little nervous. I was worried about being over 625, but I don't beat on my car to much. Hopefully the motor lasts for a year or so.

hogurt 01-11-2019 02:33 PM


Originally Posted by samwint77 (Post 1598663147)
Wow, that makes me a little nervous. I was worried about being over 625, but I don't beat on my car to much. Hopefully the motor lasts for a year or so.

I personally wouldn't push it that far simply because of the LT1 pistons. In my mind, the risk simply doesn't justify pushing it...especially if you are going to go forged anyway.

If you stick with the LT1 fuel system and just add the Maggie, you are going to have 550-580whp on about 7psi. That is perfectly fine on the stock system. Figure it will give you more power than the Z06 from the jump. Then, when you get around to adding pistons, cam, etc you can go crazy. I will tell you, you better plan on new tires at the same time. When we bumped over 800whp, driving at 50, 60, 70mph and slamming the go pedal from 4th gear...it was just lighting the tires up. . .not talking barking, but it was all over the place. That's also when it started to cool off so I decided to hold off until next summer. For me, the best street configuration with the Maggie was running just over 700whp (Cam, Headers, Maggie 85mm @8psi and straight pump e85 with no mixing required). I tested and had the car running up to 776whp with straight pump e85 with no problems. . .but on street tires, no Bueno. Next summer I will have new tires and will decide the best power level.

If it were up to me, in your first phase: 550-580whp with just the Maggie. Low cost add-ins: JMS voltage booster, front crank seal and a catch can.

Second phase: decide on 93 or e85 and build accordingly. Figure on 93octane you will probably hit the octane wall about 650whp so you will either need alky injection or e85 (or race fuel). With e85, the a8 will hit a limit on the low pressure LT4 pump (why you need the voltage booster) after that, you will hit the injector limitation around 800whp. . .so again you can address with bigger injectors FIC injectors are about $3k. You can add alky. You can use race fuel. BAM.

As I said before, I have worked really closely with Ted Jannetty. He is an absolute master for the Maggie and getting it tuned. Since my Camaro is somewhat insane, I am planning to keep my Vette more on the fun, but not obnoxious side. Here's an example of a Vette with just the Maggie:
Facebook Post

samwint77 01-11-2019 06:28 PM


Originally Posted by hogurt (Post 1598665901)
I personally wouldn't push it that far simply because of the LT1 pistons. In my mind, the risk simply doesn't justify pushing it...especially if you are going to go forged anyway.

If you stick with the LT1 fuel system and just add the Maggie, you are going to have 550-580whp on about 7psi. That is perfectly fine on the stock system. Figure it will give you more power than the Z06 from the jump. Then, when you get around to adding pistons, cam, etc you can go crazy. I will tell you, you better plan on new tires at the same time. When we bumped over 800whp, driving at 50, 60, 70mph and slamming the go pedal from 4th gear...it was just lighting the tires up. . .not talking barking, but it was all over the place. That's also when it started to cool off so I decided to hold off until next summer. For me, the best street configuration with the Maggie was running just over 700whp (Cam, Headers, Maggie 85mm @8psi and straight pump e85 with no mixing required). I tested and had the car running up to 776whp with straight pump e85 with no problems. . .but on street tires, no Bueno. Next summer I will have new tires and will decide the best power level.

If it were up to me, in your first phase: 550-580whp with just the Maggie. Low cost add-ins: JMS voltage booster, front crank seal and a catch can.

Second phase: decide on 93 or e85 and build accordingly. Figure on 93octane you will probably hit the octane wall about 650whp so you will either need alky injection or e85 (or race fuel). With e85, the a8 will hit a limit on the low pressure LT4 pump (why you need the voltage booster) after that, you will hit the injector limitation around 800whp. . .so again you can address with bigger injectors FIC injectors are about $3k. You can add alky. You can use race fuel. BAM.

As I said before, I have worked really closely with Ted Jannetty. He is an absolute master for the Maggie and getting it tuned. Since my Camaro is somewhat insane, I am planning to keep my Vette more on the fun, but not obnoxious side. Here's an example of a Vette with just the Maggie: https://www.facebook.com/jannettyracing/videos/1750704065052717/

Welp....... The headers and x pipe are already on, doh! Guess I'll just have to be mindful and keep it down. I really think just the cam and drop ins will get me where my goals are. I'm ecited and scared a little, but I'll baby her until its time.

hogurt 01-11-2019 07:59 PM


Originally Posted by samwint77 (Post 1598667358)
Welp....... The headers and x pipe are already on, doh! Guess I'll just have to be mindful and keep it down. I really think just the cam and drop ins will get me where my goals are. I'm ecited and scared a little, but I'll baby her until its time.

That's what I did too so that I could be right about 800whp with no problems.

BlueDevilZ51 01-14-2019 07:25 AM

620whp with be the limit of the LT1 stock fueling system

hogurt 01-14-2019 07:52 AM


Originally Posted by BlueDevilZ51 (Post 1598681692)
620whp with be the limit of the LT1 stock fueling system

Depends on the dyno. With the stock fuel system, we saw the fuel pressure falling off well below 620whp. Technically, the fuel might have been able to make the bare minimum that long, but certainly so wouldn’t have left my car in that position.

Are you saying 620whp with a Maggie, or saying that’s your experience with a different blower setup?

samwint77 01-14-2019 01:04 PM


Originally Posted by hogurt (Post 1598667922)
That's what I did too so that I could be right about 800whp with no problems.

You saved me some money my friend, thank you. He ordered the 75mm pulley. I'm just going to keep it and use the 95mm for now and stay at 570whp until I'm ready to do my cam and drop ins. Thanks a bunch.

samwint77 01-22-2019 08:15 AM

Shes back up and running. I stopped by last friday and the install was complete. He was beginning the tune on the car. he got it running good enough to take a ride. Thing is gonna be fun man. He said its pumping 6 psi with the 95mm pulley and off road exhaust. I will be getting it back this week. Im missing my car at this point.

samwint77 01-22-2019 01:13 PM

Well, the numbers are in, 521 whp / 556 wtq. Was hoping for a little more, but I like it still. 150 whp pick up and 167 wtq. Think im gonna do a cam and another pulley next.

hogurt 01-23-2019 10:46 PM


Originally Posted by samwint77 (Post 1598737075)
Well, the numbers are in, 521 whp / 556 wtq. Was hoping for a little more, but I like it still. 150 whp pick up and 167 wtq. Think im gonna do a cam and another pulley next.

Something isn’t right.

1. which pulley and how much boost are you seeing?
- If you had the 98mm pulley at 5psi, that sounds about right with stock manifold.
2. Did you dyno in 6th gear for the A8?
3. Did you use a Magnuson tune or a custom tune? I thought the Magnuson tune was for stock car with Maggie only...

samwint77 01-24-2019 01:38 PM


Originally Posted by hogurt (Post 1598747539)


Something isn’t right.

1. which pulley and how much boost are you seeing?
- If you had the 98mm pulley at 5psi, that sounds about right with stock manifold.
2. Did you dyno in 6th gear for the A8?
3. Did you use a Magnuson tune or a custom tune? I thought the Magnuson tune was for stock car with Maggie only...

Its the 95mm pulley, and I was seeing 6.5 psi. Not sure what gear he dyno'd in, but should have been 6. It was a custom tune.

hogurt 01-24-2019 08:05 PM


Originally Posted by samwint77 (Post 1598750442)
Its the 95mm pulley, and I was seeing 6.5 psi. Not sure what gear he dyno'd in, but should have been 6. It was a custom tune.

Only two things make any sense to me at all.

1. You dropped boost with headers and thus, you need a smaller pulley to get the same power. The open exhaust does nothing to bump power at these levels. Results with 95+headers is same as 98+stock manifold.
2. Dyno was not in 6th.

If if the low side was falling off at 520wh, that also must mean the stock lowsode on the Vette is much worse than the stock low side on the Camaro.

Truthfully, we did all of my dyno runs in 5th instead of 6th until we were about finished. My last run was 6th...but it’s scary having the car pulling that kind of mph on a dyno.




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