355z28

iTrader: (8)

I've decided I want more from the car, Right now the engine in the car is stock crank, stock rods and speed pro hyper pistons 2 valve relief flat tops 11.5:1 with the hotcam stock untouched heads.

I want to build another 355 with stock crank, eagle H beams, diamond pistons flat tops 11.5:1 fully balanced. I have a set of LE2 heads and will be getting a cam from lloyd as well. This motor will spin 7k and be taking 175-200 shot of nitrous. Will this put me on the edge of low eleven, high ten pass?

z28rob18

iTrader: (7)

idk about spinning the stock crank to 7k and sprayin that much. other then that it sounds good.

Colin91Z

iTrader: (9)

Stock crank will take it, mine sees 7k several times a day

The combo you thinking off sounds very close to what I have currently. I'm running a stock crank, scat I-beams (7/16 bolts), and Probe flat-top -4cc pistons. My CR is 11.6:1. Ported Stock heads (271/191 @ .600) and a LE3 cam. My combo was good for 11.91 @ 117 N/A in KC at the LTXshootout a few weeks ago, and that was in 95* heat with a DA of about 3200....Car weighed 3560 with me in it, and is a M6 on 17" drag radials.

355z28

iTrader: (8)

Mine weight 3580 with me in it. With all the mods in my sig. Im Just hoping the bottom end will take it with the spray. Im depating on to use splayed caps or not.

Would H beams be a must for this or could I get by with I beams? Id imagine with the shot H beams would be "Cheap" insurance.

Colin91Z

iTrader: (9)

IMO I wouldn't bother with splayed caps at this hp level. Hell I running a 2-bolt block. It should easily take 150-200 shot as long as you make sure it gets enough fuel.

H beams are not necessarily stronger than I beam, in fact my Scat I beams are rated to the same hp that Scat H beams are, because I opted for the 7/16 ARP cap screw option. And they were right and $300.

RamAir95TA

iTrader: (2)

Ditto on the H-beams, I-beams would be plenty strong. IMO, spend the money you would spend on H-beams and put it towards a forged crankshaft. Granted the stocker is plenty strong, but if you have the cash just go with a forged crank. And while you're at it, why not go with the longer 3.75" stroke and just make it a 383?

texas94z

I like the idea of keeping the stock crank. They are very strong. In fact, i have never heard of stock lt1 crank failing. Id rather see a stock crank 355 than a cast Eagle crank 355. Save the forged crank for a 383 or 396.

I wouldn't bother with a 4 bolt set up on a 355, depending on the power. Check out a main girdle from HPS. It would be a great investment if you do see north of 6800 rpms. A 4 bolt conversion costs around 600 dollars, but a main girdle cost around 225 dollars.

Details on the nitrous kit please.

355z28

iTrader: (8)

I just can't justify having a 383 if Im not going to have everthing to support it. I plan on keeping the hooker catback and stock unported intake and other stuff that would hinder the peak performance of a 383. For the performance difference I would see between the 355 and the 383 its just not worth it for the price difference.


I don't have the kit yet. When the time comes I plan to have HSW put it together for me.

69gto96z

iTrader: (13)

Stock crank should hold up fine, for a while, a 4 bolt conversion will help keep your crank from walking, but will not have much added strength benefit for the price. As for the kit, I would recommend Nitrous Outlet over HSW. I had a HSW kit on my car, and in my opinion, they are cheaply made, and you get what you pay for. Now not saying the kit didn't work, except for the crappy bottle heater switch I had that would not work and they would not replace. Other than that it was a decent kit.

1badzee

iTrader: (12)

I prefer nitrous pro-flow. You get what you pay for

slick1851

You will be fine

slick1851

Stock crank will be fine, dont dump money into somthing you dont have to.

355z28

iTrader: (8)

So I beams and a main girdle are all i need? What do you guys think about time? close to my goals?

Schweet97Z

iTrader: (35)

why are you sticking will 11.5:1 compression? Why not raise it to 12.5:1?

A20SVT00

iTrader: (13)

keeps updated, whos sells those main girdles

za355tx

iTrader: (108)

The stock crank will be more than enough. It can handle more than 700 hp. There's a handful of guys doing it with no issues. Just buy a main stud kit instead of doing a 4 bolt conversion. It'll handle just fine. As far as the rods a good set of I beams is not a bad idea as they'll weigh less and move easier than the bigger H beams. Seems like you have the right idea on things though. Good luck.

355z28

iTrader: (8)

Just still wanted to be able to run it on pump gas no problem. I want to run E85 eventually so there would be no problem with that.

OutlawZ

iTrader: (4)

Yeah you'll be fine like that as long as your pistons are quality enough to take the hit from the spray...

I had a setup much like this a few years back... Went 11.6@119 on motor and 10.40@131 on spray.... it'll be plenty of motor for what you expect..... Mine was a 6" rod Eagle h-beam 355 with a stout hydraulic roller in it and some IRS Stage II heads that weren't all that great..... but that thing straight ripped on spray.... I wasn't seeing 7K though due to my cam running out of steam... what are your cam intentions to see that much RPM??? And you better make sure that valvetrain is stout cause most stud mounted rockers won't like to see that kind of RPM for a long extended time.... shaft rockers????

i would put shaft rockers on it and call it a day to ensure your valvetrain stays stable at those RPM's..... crank will handle it but pushrods, springs, and rocker studs won't be happy about it IMO....

355z28

iTrader: (8)

Ill shift probably around 6800. the cam will be a 23X/23X most likely. Ill have lloyd spec it out for me. We were Originally talk about running his 226/230 cam, But I think I might need something different for the spray. Either way Ill get something spec'd for me.

OutlawZ

iTrader: (4)

hydro roller????? keep in mind it's gonna need some nasty heads and a STOUT cam to make power that high in the RPM band....

My 236/242 .544/.576 112lsa hydro roller from comp cams was making power up to about 6600 and then it fell off..... So what i'd do is have lloyd spec the heads and cam put the **** together with the intention of it being able to live at 7000 rpms and then base what you shift at off what the dyno rollers tell you power drops off at. If power falls off at 6500 no reason to shift it at 7K.. every combo is different so let the rollers tell you where to shift.... a 23x hydro roller probably isn't going to be able to continue to make power at 6900+.... at least none that i've seen....

I have a big solid roller with massive AFR 227's and even with that power is dropping about 5hp per 100 RPMS at around 7250. And I've got shaft rockers and all the good stuff.... The cam and heads just aren't moving enough air to support increased power all that pumping speed.... So I shift at around 7300-7400 just cause the tach is moving to fast to reliably shift earlier....