UPDATE! This doesn't sound right does it?
 

I'm having a 408 all aluminum block being built with the following.
All aluminum re-sleeved 408

11:0:1 compression

All forged internals

JE pistons

Dart/rhs full cnc ported heads 67.5cc chamber

Complete holley Efi system 102mm tb 102 intake both ported

Cam 237/242 113 lsa the duration is in the 600 range.

Ls7 lifters

Th350 trans 3600 stall

I just got done talking wit him and asked what a realistic rwhp number would be and he said 415??? That number sounds awfully low. That can't be right can it? This engine trans package costed me 16k to be built. With only 415 rwhp I'm kind of worried now.

Maybe that's totally realistic on his dyno

That just seems way too low to me. Especially with all the money Into it and seeing everyone else's combo.

Oh I agree, but what I'm saying is maybe that's what he sees on his dyno. For instance back when I had my HCI LS1 setup my guy said all HCI LS1'S are around 390 to 420 on his dyno, and guess what...I made 405 lol. That particular setup should've been more like 430 or so from what everyone else was saying

I just can't see how a 408 stroker would be sooooo low

Bottom line is the car will frigging fly if it's setup right....regardless of what the dyno says ;)

It's just upsetting because the original build was going to be a 383 and he said it would have 550-575 hp at the crank. After going with the 408 and fully working the heads I was expecting way more. I wanted to run in the 10s. That hardly seems feasible at this point. :(

With a loose unlocked converter, it will read lower on a chassis dyno.

it will have more than 415

Heads/cam 346 ls1 engines make 415-440 to the wheels FYI

A 408 should be 500 to the wheels minimum

It just all seems so disappointing

That's what I have seen. so for him to say 415 my heart sunk. I don't even know how 415 would even be possible. Unless he's totally screwing me saying it's going to be a 408 when in actuality it's just a base ls1.

If a 408 with CNC ported heads and decent sized cam only makes 415 on a dyno then something is wrong..

Don't know why he would say that

Shoot, cam only ls1's can hit 360-370

That's exactly why it has me worried. I just can't see 415 being possible in any way unless he's saying he's making a 408 when only making it a regular ls1 and pocketing the profit.

my ls2 with heads/cam made 418rwhp through an unlocked converter, I calculated my converter slip and if it were locked it would have made around 445rwhp

you can't lock your converter

he might also know his dyno is really stingy


dynos don't mean shit for an automatic other than for tuning and seeing how it responds to mods...the HP number is just a calculation and there are a million variables that can affect the output

run the car at the track and worry about that

What did you run with your setup?

I would expect ~600 FWHP & 460-480 RWHP from that
Combo. TH 350 and 3600 stall will cost at least 20 probably
Closer to 40 HP compared to M6. What is the diff?

Are you asking what rear end? It's an 8.5" 10 bolt.

I haven't made a good pass yet. Old setup was an ls1 with same size cam but heads were a little less ported. It made 30hp/30tq less than now and ran 11.67@115mph on a 1.7 60 ft in a car weighing right at 3700lbs. DA was around 800ft.

Best 1/8th was 7.45@95mph which was better.


I'm hoping to run 11.40@118 or and maybe faster if I ever get to run in good air.

If your car isn't super heavy you should make your goal of 10s. My car isn't a super performer at the drag strip.

So let me ask you this OP...say your car makes EXACTLY 415 rwhp on this guy's dyno, but runs high 10's at say close to 130 at the track...how will you feel then? ;)

Hahaha well when you put it like that I'd feel great. I understand the dyno is just a tuning tool but to hear him say that was a shock. I just want to go fast. If I run 10s with only 415 rwhp then everything is all good.