[shinysun]

He upgraded from 2300 to 2650 recently. Before moving, just tested dynorun with 2300.

almost the same setup , but 2650 and different boost level.

Before

Meggi 2300, Meth injection, GPI dropin piston-rods set (11.5:1 CR) with LT4 Gaskets (Thicker) 15PSI range. (The upper :81mm , The lower 8.8")
LT4 injector, LT4 HPFP, LT4 LPFP and stock cam.
Little bit running out of fuel. AFR was around 12:1

After

Meggi 2650, and the same setup except BAP

At first , tested 90mm of the upper with 8.8" of lower. but the boost level was 19PSI and totally running out of fuel.
So, changed 90mm of the upper with 8" of lower and the boost level was 16PSI and made the result on the graph.

Used the exactly same spark advance table. (20* around 6000rpm)

[L78toLT1]

Hey Shiny, not trying to hijack your thread but you mentioned that the LT4 head gaskets are thicker. Do you happen to know how thick they are? I seem to recall the LT1’s are .051. The reason I ask is because during my build I had to remove ~.015 from my block to clean up a small imperfection. Since I’m also running the GPI piston/rod kit and didn’t want to increase the compression above 11.5:1, I picked up some custom .071 gaskets from Cometic. The next time I have the heads off, it would be great if I could run the LT4 gaskets as the Cometics cost around $250.

[laynlo15]

So basically about 90 hp pickup over the 2300.

[L78toLT1]

You were at 16psi on the 2650, I wonder where you were, boost wise with the 81mm/8.8" combo on the 2300?

[KingLT1]

^This. Would like to see the difference with both at the same PSI. So far it's been 2300 @ 12psi vs 2650 @ 15psi comparisons. Of course you going to make more power with more boost. lol

[shinysun]

Originally Posted by L78toLT1

Hey Shiny, not trying to hijack your thread but you mentioned that the LT4 head gaskets are thicker. Do you happen to know how thick they are? I seem to recall the LT1’s are .051. The reason I ask is because during my build I had to remove ~.015 from my block to clean up a small imperfection. Since I’m also running the GPI piston/rod kit and didn’t want to increase the compression above 11.5:1, I picked up some custom .071 gaskets from Cometic. The next time I have the heads off, it would be great if I could run the LT4 gaskets as the Cometics cost around $250.

I can not remember the exact thickness now, but as my calculation, it can make 11.1~11.2 : 1 CR from 11.5 : 1 with lt1 gasket.

[shinysun]

Originally Posted by L78toLT1

You were at 16psi on the 2650, I wonder where you were, boost wise with the 81mm/8.8" combo on the 2300?

15 psi around

[shinysun]

Originally Posted by KingLT1

^This. Would like to see the difference with both at the same PSI. So far it's been 2300 @ 12psi vs 2650 @ 15psi comparisons. Of course you going to make more power with more boost. lol

It is 15 psi 2300 vs 16 psi 2650.

I couldn't make the same boost , but my point of this thread is 2650 made more boost with the lower SC rev than 2300.

What I am most impressed with 2650, the efficiency of itself. I was suffering with the sky high IAT issue with Whipple and 2300 on summer. The boost level was 15~17 psi. It went over 140~150 F very easily even with Meth injection on drag strip, so I was planning to install ice boxes or other things. However, after installing 2650, it was all gone.

[radz28]

Cool. Literally. Those were all things we have been told about those Maggies. I believe that's right in the efficiency range (so I've seen anyways), which is no wonder it seems it is very happy around there.

[gtfoxy]

Originally Posted by shinysun

It is 15 psi 2300 vs 16 psi 2650.

I couldn't make the same boost , but my point of this thread is 2650 made more boost with the lower SC rev than 2300.

What I am most impressed with 2650, the efficiency of itself. I was suffering with the sky high IAT issue with Whipple and 2300 on summer. The boost level was 15~17 psi. It went over 140~150 F very easily even with Meth injection on drag strip, so I was planning to install ice boxes or other things. However, after installing 2650, it was all gone.

What were the IAT’s comparatively during your pulls?

[KingLT1]

Originally Posted by shinysun

It is 15 psi 2300 vs 16 psi 2650.

I couldn't make the same boost , but my point of this thread is 2650 made more boost with the lower SC rev than 2300.

What I am most impressed with 2650, the efficiency of itself. I was suffering with the sky high IAT issue with Whipple and 2300 on summer. The boost level was 15~17 psi. It went over 140~150 F very easily even with Meth injection on drag strip, so I was planning to install ice boxes or other things. However, after installing 2650, it was all gone.

I understand and the results are as expected. 15-16psi is running into the limits of a 2.3 or Whipple 2.9's efficiency range. I was just saying it would be nice to see a comparison of both at the same boost level such as 8-12psi where the 2.3 is still operating efficiently. I would say 90% of those that are running forced induction are NOT pushing into the range where you are. So a 8-12psi range comparison would be nice so we can see at what point does it justify paying the premium for a 2650. (I should of clarified this in my previous post. I wasn't criticizing your efforts)

A bigger supercharger should make more boost with lower revs, that's how it maintains cooler MAT's. Boost is just a measure of restriction...CFM is what makes power being engines are simply air pumps. If you have to spin more rpm to flow the same amount of air, it will be hotter air.

[laynlo15]

I saw the same Iat's that he's speaking of on the hot summer days with my 2300, usually 145 to 155 at the big end of the track. With the 2650 the highest I saw at the Camaro Fest was about 125 in the traps and that was after setting in a long line starting the motor over and over in the staging lanes. Most of the time 115 to 120 which allowed me to run the same timing without knock or pulling timing down track. On the dyno my the 2650 would barely get to 110 (Iat's) even back to back runs. Plus it made about 85 plus rwhp on about 3 to 4 lbs less boost with an 80mm pulley. I haven't been back on the dyno with the 75mm pulley so I don't know what it was making with that pulley but would guess another 20 to 25 rwhp I was pushing my fuel system with the 75 on the 2650 so haven't had a chance to run the 70mm since my low side was dropping to low 40s. Maybe this year when I get the DSX low side installed. Hope I have all my numbers right as I'm thinking back to last year how it all played out.

[gtfoxy]

Originally Posted by laynlo15

I saw the same Iat's that he's speaking of on the hot summer days with my 2300, usually 145 to 155 at the big end of the track. With the 2650 the highest I saw at the Camaro Fest was about 125 in the traps and that was after setting in a long line starting the motor over and over in the staging lanes. Most of the time 115 to 120 which allowed me to run the same timing without knock or pulling timing down track. On the dyno my the 2650 would barely get to 110 (Iat's) even back to back runs. Plus it made about 85 plus rwhp on about 3 to 4 lbs less boost with an 80mm pulley. I haven't been back on the dyno with the 75mm pulley so I don't know what it was making with that pulley but would guess another 20 to 25 rwhp I was pushing my fuel system with the 75 on the 2650 so haven't had a chance to run the 70mm since my low side was dropping to low 40s. Maybe this year when I get the DSX low side installed. Hope I have all my numbers right as I'm thinking back to last year how it all played out.

I’ve noticed, to the best of my research, Edelbrock seems to have changed their Stage 1 kit from the 2300 to the 2650.

It’s great to see the data at higher manifold/ power levels, but compressor maps being what they are, I am curious to see some comparative data between the two on a stock SS at stage 1 manifold pressures.

[ssmofo]

Ask Ted Jannetty, he recommended the 2300 for my SS, he has data.