Ok guys I'm going back to NOS on my 383 lt1. I talked to a guy that has built engines for 40 years... He freaked me out today. He told me on a lt1 that is punched to a 383 the cylinder walls cant take much spray. I told him I want to hit it will a 200shot. He told me that is to much... My question is from people that have been there. How much spray can a 383 lt1 safly take? and what all do you need to do to the block... I already have forged 6.0 rods and crank and pistons... We are just talkng about the block. Respectfully Champ

 

Whats rotating inside the block and the tune should be more of a concern then the block it self. I have seen many 175-200 shots on bolt on and cam only LT1s. We sprayed a 300 on a friends 383 LT1, car ran well.

 

.030 over is not a big issue I saw a 383 lt1 about 2 weeks ago the guy had two 175 stages on it no hard block or nothing worked fine he said he had like 30 passes on it I assume it was doing good when it scraped the bumper lol a guy a know of over on another forum is spraying 175 no problem I have plans of spraying up to a 200 shot if I can get a tune to hold it on my 383

 

on a 383 you are only removing .015" from the cylinder wall so I would not worry about wall thickness being a constraint. A 383 has the same cylinder wall thickness as a 355 so that makes no sense to me why he would have said that. Is it a 2 bolt block or have you done anything with the mains? The compression height of those pistons may be worth taking a look at if you are running 6 inch rods.

 

Yah I will get it tuned 100% And I'm not worried about the Internals they are all forged... This guys just said the walls warp on the lt1 if they are stroked... I wanted to say BS to him but he has 35 years of exp and owning a engine shop and race teams over me...

 

Its a 2 bolt with ARP everythign right now. but I'm thinking of making it a 4 bolt main

 

i had 175 on a stock motor for 5 years and plan on putting 200 or more on my 383 when its done so hit it and dont worry if the tune is right

 

Sounds like 35yrs of dipshit experience.

 

The concern you should have was it setup for spray ( ring gaps most importantly )

fuel system up to par?

tune being the last important thing

200 + should not be no issue if the 3 above mentioned things are in order

I sprayed 200-250 on my old 383 car with 2 bolt mains and never had an issue.

 

He probably saw someone run too much/poorly setup nitrous back in '73 and blew their motor sky high has sworn against nitrous ever since.

Engine tolerances, technology, and nitrous have come a LONG way in recent years.

 

Cylinder pressure is cylinder pressure. Why would it be different than a 383 with boost? Going by what's in your sig.... hope you put different pistons in that thing.

 

Ring gap, not sure how important that is, but Mahle lists gaps for specific amounts of nitrous

-Dustin-

 

This means a lot to me coming from you! I've always respected your work!

 

x2.. KB pistons dont like nitrous to much. i would stay under a 200 shot..

 

Yah I ordered JE forged flat top NOs pistons and the engine builder gave me KB. Thats the last time I order a pre made Crate motor form out of state!... How much do you guys think the KB forged flat tops can take being safe?

 

i think you could be ok on the KBs if you keep the tuneup safe and dont try to push it. i'd start with a 100, adjust your jetting for the 150 based on what you learned from the 100, etc keep the timing conservative and run more octane than you think you need.

 

How do you like that E85? It looks like i'm going to be about 12.2.1comp ratio... What size injectors would you say I need for this 383 on a 150 shot?with E85?
Also What plugs are you running? Do you DD it? I'm guessing not with the gear... And how often do you change the plugs? What would you think I should gap the plugs at? Thank you!

 

e85 is great but the fuel system can be a pain when you start making power. I'd use a 42# and if you run out of injector raise the fuel pressure. You'll start to run out of fuel on a single 255 at the ~450rwhp level. I run 60# motrons on my motor and I'm using a ~500lph fuel pump.

 

I use a r5671a-8 plug at .030 gap. For you... use a br7efs plug for the 150 shot, its a non-projected 7 heat range plug. Except for cold startup, if you keep the idle lean at around 1.00 lambda the plugs do fine on the street. I had them on for ~1500 miles before i tore the motor down again. I used to drive it quite a bit when the t56 was in it, I probably won't street drive it too much anymore... 5000+ spragless converter would cook the fluid on the street even with the two huge coolers I have on it. The car is pretty loud, and california hippies wouldn't like the 4000rpm cruise.

 

Where is the fun in that??? Put the 6 speed back in
I run 8's on my 383 with a 200 shot its all in the tune. My tuner makes these cold plugs drive like 7's. Also I think I had a house near cockenballs at 1 point in California. Is that near Hanford and Fresno?

OP if you are spraying over a 200 I would go with direct port. People cook the motor on plate kits due to the fact of uneven cylinder distribution of the extra fuel and nitrous. Its basic physics if you think about it. Plus direct port hits harder than Ike fist up against Tina's face