fmijares

I am building a forged ls1 for a c5 but I feel like I can get better feedback here for this question.

What would be my best choice. I want something that hits hard and its not going to get walked by LSA supercharged cars and turbo cars, I know the centri blowers can be lazy if not pullied right. The max Power I will be looking to make is 800whp. I also want to take advantage of the 7000 rpm redline for the longer gears


c5 coupe

mamo 220 heads
222/238 cam
wesico pistons
callie rods
stock crank
IW 10% OD pulley

lt1z

For 750whp none of the above. I'd go with either a Ti trim ( 1500HD) or a D1-SC. Those will hit harder then the larger blower slowed down to keep them under 800whp.

Detoxx03

D1SC is what you want.

fmijares

thank you guys for the feedback. I guess a D1sc or a 1500 depending on the deal. what about pulley size ?

algZO6

Ti-trim for sure

Detoxx03

I ran a 3.85 on mine but it made over 800rwhp

winters97gt

Pulley size depends on your balancer size.

xBoostx

D1sc with a 8.5 bottom pulley and a 4 inch top will put you about 750 whp and no problem with belt slippage use with their race bov, you may have to buy a custom 8.5 inch pulley not sure is available but just send out the one that fits and have it made larger diameter, I had a 9" made but it was too much low end torque and too soon so an 8.5 will be perfect.

The engine is a four inch stroke ls2 head intake port flowed only 311 cfm and with the 9 x 4 pulleys made 841 whp @ 5114 (rpm) and 900.4 (ft-lbs) @ 4649 (rpm) at 19.5 psi as you can see no need to rev nothing when used with a larger lower pulley, that was revving the pump to 56000 at around 6,300 engine rpms.

The D1 max speed is 62000 so not even close to max out with the 9 x 4 combo. Hope this helps

Here's a pic of the dyno sheet

Slo-Poc

376 with a D1

CI GS

The OP has stated that he’s running an IW 10% O.D. balancer, which has an 8” dia. pulley size (and ~8.25” overall dia.).
BTW: I’m not sure about fitment on a C5, but on the C6, that size barely fits in between the stock sized water pump pulley and the engine cradle with enough space to get a belt on. So, I really don’t know how you could fit an 8.5”, let alone a 9”, crank pulley balancer on a Y-body setup, without a custom water pump pulley and a tubular engine cradle?

xBoostx

In the case of the gto above was ok just had to move the fans away by modifying the alum shroud but there's always a way a quarter inch larger means just 1/8 to each side so it will only seen like an 1/8 closer to water pump.

A remote electric water pump comes to mind and helps to un shroud the area a bit with the use of -AN hoses.

CI GS

At the risk of derailing this thread, since the OP has already stated from the outset that he has an IW 10% O/D balancer, I thought I should share my experience, before someone reads this and thinks that they can stick a 8.5”or 9” PULLEY on one of these Y-body cars.
I get that we’re talking about radius rather than diameter, but if we’re talking about actual pulley size, then we have to factor in the pulley flange and the thickness of the accessory belt that runs between the water pump and the balancer. When I bought the 10% IW, they told me that they made a 15% O/D for the Y-body, which has an O.D. (overall diameter) of 8.35”, iirc, but they said that it probably wouldn’t work on the stock water pump because the belt might touch the balancer where it loops around the WP pulley. I’ve since read where one person has gotten it to work though. Again, the OPs balancer has an overall diameter of 8.25”, which has a 8.00” PULLEY. I’m sure I have pictures of the gap between the pulley flange and the WP pulley, as well as the gap between the crank pulley flange and the engine cradle, if any needs themes see what I’m talking about.
I have researched this extensively and I haven’t come across a single person that has either a 8.5” or 9” pullied balancer that can work on the C6, simply because it couldn’t fit unless you add spacers between the frame and the engine cradle and use a smaller WP pulley. If you know of one, I’m all ears.
Apologies to the OP for the sidetrack. I’m sure that whatever blower you choose, you don’t need to think about changing your crank pulley.
FWIW: I would defer to and agree with the folks like lt1z, Detoxx03, alZ06 and Slo-Poc, who have advised you on your actual query, as they know far more about centrifugal blower setups on these cars than I do.

TTBlueZ06

For that power I would recommend a Ti, power delivery will come in hard and it will be running in its peak efficiency range. Go YSI/2200R if you want more.

C U IN REARVEIW

Im about to do a 3.4" pulley on my stock dia Ls2 balancer w/ ti-trim......what kinda power am i looking to make? I was just hoping to make 700whp.....will i be over that?

* i know setups vary due to mods....ballpark #'s *

Unreal

Ti or D1

fmijares

realcanuk

Too much blower for your goals. Some smart guys answered your question but what fun would be taking that advice.

fmijares

I don’t think I understand. Everyone here recommended the d1sc. I looked up the specs on all of them and the d1sc flows 1450cfm exactly like the novi 2200hd. The only difference was that one was oil fed and the other one was self contained. How is one blower too much blower when they both flow the same ?

realcanuk

I haven't looked at specs for awhile but unless things have changed a 2200 would need a larger pulley to limit it to 700hp. You can go that route but I would rather have a blower that's in its efficiency range where you drive the most.

Creamo3

You can max out a Ti or D1x around 900whp / 2200/yis is around 1200whp. Get the blower that is most efficient for your power goals otherwise it will be lazy down low and you'll get walked by LSA and turbo cars that don't have the same "lag".