JohnsTA

i blew up my engine and am looking for a nice replacement. been thinking about the 402 that sdpc offers. looks like heads+their setup puts me in the $6500 range. then another G for tuning and cam and minor parts. i hear numbers of about 550 hp for a good setup out of this engine. can anyone confirm? if im going to be spending 8K for an engine i want a minimum of 550-600 rwhp out of it. any other high hp options available?

DrkPhx

iTrader: (15)

It's gets expensive real fast when doing a large stroker. Gaskets, bolts and new sensors (I recommend them) are not cheap. You didn't mention an intake; without question you need the FAST 90mm Intake with a 90mm TB which adds another $1200. I also recommend the AFR 225 heads; these heads were designed for these larger cube applications and are the perfect choice.

Before jumping into a stroker you need to figure what your goals are with the car and what your total budget is. Remember at that horsepower level the rear end, fuel system and tranmission/driveshaft need to be upgraded to handle that power level. Those components add a lot of $$$ into the equation and need to be taken into consideration. Basically if you go stroker do it right and don't skimp on parts, otherwise it come back to bite you.

Finally I would recommend calling Mike at Rapid Motorsports and Kris at SDPC. Both have good knowledge of the LS2 402 and will give you straight, no BS advice.

JohnsTA

well, that was my other concern. when do the injectors and fuel pump run out? i was planning on using my ls6 intake. i have a 2001. im only looking to get 550 rwhp and staying NA. I am going to put a th400 in cause im tired of breaking 4l60es.

are there any other alternatives to making big power for the same price? stock motor with a blower? if im going to be taking this motor out, i want a bigger one going in. i figure a rebuilt stock motor with a blower will still cost similair to a stroker.

DrkPhx

iTrader: (15)

You would need 42 lb injectors and a higher flowing fuel pump. LS6 intake on a 402 stroker will choke it; you can run it but it will hold the setup back.

Beast96Z

iTrader: (21)

If you planning on 550 rwhp through the TH400, you better start scraping some money together. Futral did it with a 408, but there was lots of money tied up in that car. Like stated above, the sweet combo right now is the 402 with AFR225's and the FAST 90/90 set-up. You'll never see 550 through the LS-6 intake. As for fuel, if you stay N/A, you can use the Racetronix plug n play kit. It's a very nice in tank kit.

JohnsTA

dangit. this stupid cars getting expensive.

how badly would the ls6 choke it. i dont have the cash to plop down on a all of these parts at once. could always throw the fast on it over winter. or maybe ill just repair the damn engine.

5POINT7

Don't fix the engine if you "blew it up".

You have a daily on the side? If so, ride around in that and just save man. It'll be worth it in the end.

89FormulaLS2

iTrader: (1)

I'm still waiting to see some definitive graphs on the LS6 intake versus the fast on a stroker. I've asked a few times, nobody seems to have apples to apples comparisons.

FWIW, TPIS has had awesome results with their LS6 intake modded to take their 90mm TB. And on head to head comparisons, even the stock LS6 intake seems to stay right with the FAST all the way through the power band, only giving up 5-6 peak hp - hardly making it worth the extra expense.

Still, I've heard more than once that the FAST is needed for bigger cubes - but I wish someone would show some actual TEST RESULTS that would prove it. I don't really want to plunk down the extra $$ unless it is going to give a substantial gain on my LS2 402.

cyclerage

iTrader: (59)

I just finished intalling the SLP 402 in my car, the conversion wasnt that bad. When I got it, I had it checked out by a second party to make sure everything was true, and it was and also swapped the stock main bolts for some ARP's. The SLP kit was about 4K. and it comes with alot of the parts you need to make the LS2 in your car. I havent been able to get on it yet, still need to finish breaking it in. I'll have more info soon.
J

CHRISPY

Rapid will put you together an LS2/AFR package that'll make well over 500RWHP with the LS6 intake no problem.

pkincy

iTrader: (1)

42s and new fuel pump are correct. I do agree that the LS6 may choke the motor above 6300 rpm and cost you about 10 peak rwhp, but the motor is so AWESOME at all other speeds who cares. Run it that way til you save the 1400 bones it takes to put on a new intake. I am.

Perry
98 1LE with LS2 402 from SDPC with TEA stage 3 6.0 L heads (72cc chambers) LS6 intake, ported TB, Torquer Cam, Lucas 42s, Racetronix in tank plug n play fuel pump. $8k lighter and HAPPY!

FEAR THE LS1

iTrader: (1)

You might be talking about my motor. I made 585 rwhp with my FMS solid roller 408 and my drivetrain (TH400, 12 bolt etc). When I think of what it will take for a 402 to make 550 rwhp NA with a TH400, I don't see it being streetable at all. Definately do-able..but in a race car application. 550 rwhp would mean the 402 is putting out 700+ hp at the crank..not possible on pump gas normally aspirated 402.

A more realistic rw power # for a streetable 402 could be in the 490's with all the goodies. Please note: this is a TH400 drive train not a 6 speed..

JohnsTA

well, i talked to kris....he suggest to stay with the ls6 intake for now, till i can afford otherwise. so this is what i have planned (in my head )

their basic 402 ls2

he said 30 lb injectors should be enough, also said stock pump should be able to handle it... anyone else care to comment on this?

240/248 cam

ls6 oil pump.

gonna either go with the afr 205s, or see if i cant find a set of used heads cheaper. trying to save some money.

slap that all together and hopefully with the big cam it will help offset the "ok" heads and "ok" intake. money IS a factor, so i will have to deal with it till i can come up with more.

im undecided on whether i want to go with the flp 4l60e, or look into a th400.

any comments or guesses on rough hp numbers or drivability?

DrkPhx

iTrader: (15)

John - Injector size depends on actual HP as does a bigger fuel pump. I would upgrade with a new fuel pump and 42 # injectors simply because you will need them down the line.

While a good cam can be used as a "crutch" to help offset low head flow numbers, putting a set of heads designed for a smaller bore will not allow the engine to realize it's true potential. I feel the same way about using a LS6 intake and a 78mm TB on a large stroker ; it can be done, but ultimately it will hold it back. Look no further than stock bore head/cams cars switching to the LSX/90mm and gaining 15 rwhp over the LS6 intake. It's your call. Give Tony at AFR or Mike at Rapid Motorsports a call for better insight.

Slowhawk

iTrader: (12)

I just finished installing a SDPC 402.Car runs great.It is 9.5-1,AFR 225 heads,232/238 on 115 Cam,Kook stepped headers.As you can see it will have a blower on it soon I did a partial run and it put down 400lb's of torque from 3000rpm to 5000rpm (stopped the run) and HP hit 380 at 5000rpm with only 22 degree's of timing.When the motor has some miles on it we'll flog it on the dyno with alot more timing/leaner A/F.I expect 460hp/450tq out of this low compression setup.

Mike TexaSS

iTrader: (2)

I have a LME 402 LS2 that I will be installing in my 1999 FRC Corvette next week. Stay tuned for Texas's first LS2 C5!!

Sam88Gta1

iTrader: (13)

Mike.........We are almost done installing a 402 ls2 in a 03 Z06 here at Fastech...Should have the car on the dyno about 4 pm tomorrow.

2nd 402 C5 in Tx is still cool.

Mike TexaSS

iTrader: (2)

Doh!!!

cyclerage

iTrader: (59)

Mine is done and running great! I'm just putting around trying to run the miles up(Did I say that?) Its got about 300 on it now and all I can say is half throttle at 2500rpms= zerop traction.
I went with the SLP 38lb injectors and plan on upgrading the fuel pump to a racetronics in a week or so.
I have GM LPE-LS6 heads, 248/252 .629 lift Compcam. It idiols nice!

pkincy

iTrader: (1)

That is a huge cam. But I love your "idles nice" statement. No bucking or surging?

I completely agree about the awesome "off idle" power. The strength of this motor is in the drivability. One of these days I may hit a dyno or a dragstrip but right now I am simply drunk on the awesome power and drivability of it.

Perry