ReeknHavic

I'm thinking about either a 416 LS3 topped with L92s and the FAST (when it comes out) or a 427 with LS7 heads and the new FAST. I understand the 427/LS7 is going to cost more. My question is using the same size cam, say mid 23x/mid 24x how much more power will the LS7 headed engine make over the L92? Are we talking 20-30rwhp or more? I've also been told that I can make the same power with a smaller cam with the LS7. I'm interested in around 550rwhp and I want it to have decent street manners. I appreciate everyones input and look forward to learning something. Thanks guys.

Dutchman427

iTrader: (1)

Go with the LS7. #'s are in the sig. I am running 12.1 cr. Has exellent street manners. If I would have kept the 10 bolt in when Mike @ Rapid dynoed it. It would have been very close to 600rwhp.

slow trap

iTrader: (22)

i think if you can afford it go ahead and get the 427 or even a 441 is around the same price. the ls7s seem to easily be over 550 rw even with a mild setup.

MPM IV

iTrader: (3)

If you're starting from scratch why limit yourself to 427? I understand if budget is a concern, but I've never known anyone that later wished they had gone with a smaller motor.
My results are in sig.

ReeknHavic

Who do you recommend getting a 427 shortblock from guys?

ddcarter

iTrader: (14)

I see you are in Olathe. I am down the road in Emporia. I went with LS7 block and heads. Cost a little more now, but a whole lot more latter to go bigger.

BigRich954RR

iTrader: (1)

Shortblock LME Id say 427. Ls7 heads will make little more power but a trickflow 245 head engine will make a little more mid and TQ

At 550RWHP your could go both ways and be happy at 600RWHP ls7 will start to shine but will start to kill low to mid numbers and DD fun

XtraCajunSS

iTrader: (2)

I'd agree on the cathedral port vs LS7 headed comparison. The TF's are more apt to make torque below 3500. Even in stock form, LS7's don't really turn on until 3K+... It all depends on your driving style and trans choice, if you are running a 4K stall auto car, LS7 all the way. If its a stick car and you don't want to be a clutch destroyer or run 4.56's do the smaller heads.

Shane

99blancoSS

iTrader: (115)

I will throw our name into the hat for consideration for your shortblock. We distribute HKE precision racing engines.

Paul418

Reek, would you happen to be Aaron? I've been talking with a guy in Olathe about a new motor and wondered if it was you. If you want to see/hear/feel a 418ci forged LS3 just send me a pm and we can arrange something. I'm near 147th and Antioch. There is an annual "Corvettes on the Square" in Independence, MO tomorrow/Saturday morning until about 2 p.m. I plan to get there around 11 a.m.

Cliff

iTrader: (19)

Go 427 with the best heads money can buy.

ChucksZ06

iTrader: (9)

I am doing a ls7 block with wiseco pistons that allow me to use 92 heads or ls7 heads. I already have the l92 heads and intake so that is going to be cheaper. It looks like the ls7's are another 50hp though.

Rookie

I think all the LS 427s are great. I bought my motor for around 7200 long block manifold ls 7 inj upgraded springs and a big duration cam. Hooking up is a real problem with traction and I also upgraded the RPM tranny/trq converter and rear 3.42 along with shocks. Make sure you have done your homework on your fueling system as fuel starvation was a real issue for me with my 98 vette. Make allowances for a larger pump large injectors and a regulator and some other necessary items like good headers and air intake, maf and on . A larger radiator/oil cooler/tranny cooler etc.
I went with a stroker because I like torque and the price was 1/2 of an LS7 based motor. There are also allot of details you have to pay attention to depending on the car you are putting it in so check those out as well.
Good Luck with your choice as it is hard to go wrong with either but the price and torque was what sold me on the L92/LS3 427.
Regards,
rookie

99blancoSS

iTrader: (115)

One thing that may influence your decision is the LS7 block availability and cost. At $2750 before delivery your better off going with a Darton sleeved LS2 instead. You can have a bigger bore and more cubes and better sleeve material for the money that way as well.

For a long block with LS7 heads on top your looking at around $12,000 from us for a 427 (4.125 bore) with Callies crank and rods and Wiseco pistons. This would be for one of our HKE precision race engines. We'll cam it to your application and driving it will not be an issue.

You should see north of 550 at the wheels with 427 cubic inches and a proper top end.

Gordon0652

iTrader: (4)

Go for the LS7 and make it a 440! It's basically the same price!

& spray it!

tals7

for motor (ls7) try thompson automotive in wixiom mich.jon lahone(built robin l,s motor)built mine it made 660hp on there superflo(with stock quad flos).car not dd but could be.

1FASTBIRD

iTrader: (21)

I second that motion