viper8u2

Cracked my cylinder 3 wall about 3 weeks ago, finally getting over things and getting things rebuilt. Wasn't doing anything special when it gave out. In fact, I didn't even know anything was wrong until I went to leave and smoke came out of my exhaust. Thought it was probably a head gasket. Old build was stock LS7 bottom end, heads redone, A&A Vortech V3-TI, AR headers, Ron Davis Radiator, etc

The car put down 630 rwhp and 560tq with 7# of boost (was trying to run safe until I had a forged bottom)





Anyways, I have a new Concept Performance LSR block coming and debating on some things for the new build.

Just wondering what others are making for power with similar specs, it is a summer toy and I am not tracking it but do like some spirited runs. I am wondering what the max HP guys have been able to do with straight 91 pump gas. Thought about ethanol but like I said really looking for reliability (as much as I can get with a modded car) and no hassles with meth etc

what have you guys done for that balance? I would like to shoot for 800rwhp, but probably thinking I need to be running meth or e85 etc

DRM is doing a full forged blower motor now for me

Mike

Unreal

You will need meth, or flex fuel/e85 for higher power. 91 just won't have the octane to safely do what you want. If you had meth on the old setup, it probably would be alive today.

Patriot Six

Yes, you will definitely need meth with 91 octane. I made 750whp on a Mustang Dyno with a forged LS7 (10:1 compression) with a V-3Ti and 3.4 pulley on 91 and meth. Car also had a mild blower cam and ARH headers.

Since then, I have installed the new A&A secondary drive with 8 rib. With the stock sized balancer and 3.47 pulley, I gained 2 lbs of boost. This time on 93 octane and meth, it made 837whp on a Dyno Jet.

schpenxel

Agree with previous posts.. more octane, more power, less broken stuff.

BoostedC3

Can't go wrong with Ethanol! Make sure you test the station you get it from however and its not coming in at something like E50

schpenxel

Test? Psst, get a flex fuel sensor setup and let the ECM deal with it.

BoostedC3

You can defiantly do that and the ECM will keep you safe but with a lower octane the computer will pull power out. Regardless of flex fuel, lower the octane will result in lower power. My local station actually came in at like E90 last time we checked

My car will be going Ethanol very soon. Not to hijack but any preferred kit for flex fuel?

Unreal

DSX kit, the original, best quality, support, and Dave rocks.

viper8u2

thanks for the comments, this is new territory for me so I will need to discuss with my shop. so what meth kit are folks using these days if I go that route? Are you guys running meth and e85 conversions together?

Unreal

Alky control

Yes plenty of people run meth and e85 together.

For 700-750rwhp, one or the other is more than enough. For 1000+ both can be helpful.

neverstop

meth is no brainer. imo should be the first mod after the blower for everyone

stevieturbo

You can easily make good power on 91....just dont expect to do it with a high CR.

If using 91 is a necessity...then just build to suit.

If you can add octane/detonation suppression by other means then you can choose to use a higher CR.

Either way it's just about building the right package for your needs.

viper8u2

well was down at the Street Machine Nationals all weekend and had a chance to talk to a lot of folks. Seems E85 Flex is the way to go. Going to look into that more. I need to figure out what to do for my fuel system, Not sure if the folks building my motor will be doing the e85 so they will probably be tuning to pump 91 then I will bring it to another shop that has the flex setup. Any recommendations on fuel system?

stevieturbo

It would be pointless building a setup to specifically run 91...then run E85.

The two can allow vastly different end results, and take the initial build in very different directions.

ie, E85 will want a high CR...91 will definitely not.

if you're wanting to run a combination of both, then either you will need to know how much ethanol is in there, or whatever controls you are using will need to ensure you can never run too much boost etc when there is no ethanol in the fuel.

neverstop

e85 is amazing stuff and vastly superior to 91 obviously and if you have it locally but seriously just 91 pump gas and a methanol kit can easily get you 800+ whp. I'm making 900whp with 91 and dual methanol and been very reliable with 9.75:1 compression. e85 makes the fuel systems pretty serious which can get very complex on these cars, if you're ok with making just 800whp near term I'd just go with simple alky control meth kit and run pump gas and a ECS or A&A external fuel system. e85 is great but not necessarily needed and a top notch FORE fuel system is expensive and seems like a lot of people take time to get them perfect or sacrifice reliability. e85 is better but imo not absolutely necessary and always something you can do later. the difference on my car between 680whp and 860whp was absurd so I bet you'll be happy with 800whp for a bit and can always go back and upgrade fuel system for e85 later and then just have both meth and e85. just my $0.02

viper8u2

appreciate the input guys, made a few calls today and got a few opinions. to make more than 750-800 I would probably need to jump up to the YSI, that combined with everything else for flex/e85 is quite the jump in funds that I don't really have now. I will get the A&A external fuel system and it was recommended to me to go with the Jam Cam by Josh @ A&A and probably tune for pump 91 now until I can do the rest late

Unreal

Anything past 800rwhp gets into a $40k+ build if you want to do it correctly.

neverstop

this is very true.

a meth kit is like a few hundred bucks and seems crazy to not put one on there at least given what you have into the build. the octane of 91 is just not good for these cars past 650whp imo. I would not feel good driving one of these cars past 650whp on pure 91 octane anyway. If you really go down that path i'd at least put a can of torco in each tank of gas.

speedz06

I want to warn you to check the block before buying a sleeve if you plan to fix that cylinder.
mine cracked #3 just like yours and looked like a small imperfection but once the liner was out we found the block cracked in the same spot. This can be avoided though.
Good luck with your new build.

viper8u2

it went through the water jackets

Already have a new block, concept performance LSR

JE Pistons will be 9.5:1
Jam cam
Etc

Thanks for the feedback/info