F-Body Europe

I have been looking into changing my engine over to the LT4. Jim Pace sells a conversion kit for $2,300. It includes complete heads, intake, LT4 "Hot Cam", and all gaskets needed to do the job. They claim 425 HP I am guessing that is at the flywheel. Plus you will need to have the computer redone for it to run propperly.

So here is what I want and then I have a few questions.
1. I need to stay emissions legal.
2. I want as close to 450-500 RWHP as I can get. Don't know why, it is just a goal.
3. I was looking at doing this LT4 conversion and then putting a ATI ProCharger on at 6 psi. My estimates are that should put me at 480 RWHP.

Questions:
1. Is $2,300 for the LT4 conversion a good price?
2. Are there different head/cam packages that are cheaper, but still offer the same HP gains?
3. Is 425HP a realalistic (sp?) HP # from the LT4 conversion.

Got more questions, but duty calls. Later

Well yes that is a good price but you can get more from ported LT1 heads for cheaper.

That being said, 425 (flywheel) is right on the money, I seen that combo dyno tested awhile back. If you want to stay emissions legal and make that kind of power, you will need some un-natural aspiration. After that 6lb charger is on for about 6 months, your engine will decide to puke and then you can look into a rebuild.
You cant beat the hotcam package for bang for the buck! I can attest to that.

Rob has a great combo that consists of LT4 hardware but better, he should be emissions legal and be damn fast also.

Care to comment on this one Rob? This is right up your alley!

Depends on how hung up you are on having a Red Intake. Its a good price (I went with Scoggin-Dickey, same price except they offer CNC'd heads for alittle more). They add is refering to a build-up in "Chevy Highperformance" or something like that. It made 429hp, but keep in mind, that was with LT headers and a MOTEC controller on a engine dyno, (read no parasitic loss).



To stay emission legal, your gonna need a good set of shortie headers, LT's are not emission friendly.
425hp from the LT4 gadgets should equate down to 340-360rwhp with the right PCM, exhaust, and supporting cast. A ATI (I think 8psi is the lowest) may survive awhile with a good tune, and constant maintenance (gonna be fun checking plugs every month), cuz you gotta figure 1-2psi lost in the intercooler. 6psi should bump your CR to around 13:1. The price is good IMO, but 450-500rwhp is kinda high with what is know as a mild setup. If power is what you want, port your heads(GTP), and go with a more aggresive cam (CC306 or similiar). This will start getting boarderline sniffer friendly, but will get you closer to 390-400rwhp. Your gonna need all the little extras also to help squeeze out the ponies. If your gonna blow it, build it now for it, or pay double later. Cheaper but just as effective is 50-75hp N20, which is a hit a 350ci can shrug off with little to no worries.

I will dyno mine soon, and you can take it for what its worth, but bottom line 425hp is about 75hp to optimistic with just a LT4 conversion.

This is where it starts getting pricey

Krazy
If you run ablower with the LT4 Hot cam ,you will be blowing a lot of horsepower out through the exhaust due to the unusually large amount of valve overlap . There are a lot better and more eficient cams for a blower setup.

Thanx for the info. I know there are specially built cams for blowers, but the blower will not be put on for a few years down the road, if ever. I am looking to do the LT4 conversion this year. Hopefully very soon after we get to the states which is going to be in August. I have the money for it right now, but we have to pay to ship one of our cars back to the states and we don't know what kinda job the wife is going to find right away when we get there so we are hording the money away for a rainy day. Hopefully there won't be a rainy day and I can order the kit within a month of hitting the states. I was kicking the nitrous idea around, but I have never actually used it or even seen a car that had a working system on it. I am use to the superchargers and I know what to expect from them. My Honda had 10.1:1 compression and I ran 8psi for over a year and then upped it to 11psi for 6 months without a single problem. I honestly believe it is all about how well you set the system up and tune/maintain the engine. If done propperly it will be safe. Of course not to start any wars, but the truth is Honda engines are built to tighter specifications than Chevy engines, so they may handle more abuse. I would probably be very happy with the LT4 conversion and then 50-100 shot of nitrous for track days or when I ran into a little trouble. Basically I want to know what is avalable for emmisions legal head/cam packages. Here is what I figure I would do and you guys can correct or add your suggestions:
LT4 heads (stage 1-2 port/polish)
LT4 intake (port/polish)
LT4 "HotCam"
Shorty headers
52mm Throttle body
High flow cats
ECM rewrite to match completed package
Hopefully a full Dyno tune when doing the computer, so everything is set up safe and right.
Nitrous kit with all the goodies (just in case)
Of course they make cams just for nitrous also, but I would still keep the HotCam. Do you think this would be very streetable and pass emmisions? Remember this is my daily driver. Then all I would have left is the suspension and brakes. Going straight fast just doesn't do it for me all of the time. I'm more into the corners. This is just so I can get to the next corner faster:) Thanx for all of the help.

P.S. Almost forgot, I am thinking 4.10s in the rear. I am worried about traction, but 6th gear is worthless right now and I can't drive even close to these speeds (legally) in the states. They can take 6th gear out of my car as far as I am concerned. And I am being serious, my car very, very seldom sees 6th gear. So what are your opinions on 4.10s with that set up. I am not super worried about 1/4 mile time's, I mean I would love to get into the 11's, but as long as the car is fun to drive I'm not looking to break any records or squeeze every last 10th out of it. Peace

Your honda probably had forged internals, and its no secret that the 2bolt main 350 isnt a work of engineering might. Put 6psi on a stock LT1, and you've committed yourself to a rebuild. Maybe not today or next month, but it will go.

Like I said before, unless you want the LT4 stuff, dont bother going with it. Ported LT1 heads will flow just as well. The intake doesnt need anything, except maybe matching it to a larger T-body. With headers, look at something like the AS&M kit @ Thunder. I would estimate the your above combo to put down around 350rwhp.

Where is the best place to get ported LT1 heads complete and intake? And what are we looking at for cost? Would I want stage 1 or 2? Thanx

Krazy
I believe the term which is found on the LT4 Cam BOX will sum up whether it is emissionlegal or not . "FOR OFFROAD OR NON HIGHWAY USE.

Go with the LT1 stuff, you already have it so it will save you major cash. Any cam bigger than the CC305, then it gets "hard" to pass emissions with. The hotcam will pass easily with a tune.
You can go with a local porter who know what he is doing and you will save cash and get just as good results as a big name porter.Just make sure they have done LT1;s and have a flow bench. Big name porters are exspensive ie. GTP, but they are proven to get results. Its just how much you want to spend.

Jeff

P.S I like the 4.10s, you will need some gears for about any cam you do anyway.

Need some examples? GTP will charge you $2000 to port your own heads.

Granted, that nobody has really stepped up and challenged them for the most potent package (they typically dyno 400+rwhp)

I think it will depend on what state you goto for an emissions inspection. Lt4 hot cam will never pass in California. hdrocarbon and Nx counts will be too high.

I would give you some info but Rob, Roy and Jeff pretty much summed it up. The LT4 package is the biggest bang for the buck you can't beat it. I have known people to get the entire kit for around $1700.00. I have know idea where they got it from but if you ask John (ZBLKHELLRAZR) he may be able to square you away with some of those killer deals he finds. Good luck and as Rob said do it right the first and you'll save alot of money in the long run.

Don't worry about that I do not plan on living in California, that state hates performance cars. I am moving back to Phoenix, AZ. That is were the wife is from and it is a rebel state. Not as in rebel south crap, but that state tells the rest of the states to F off with alot of the rules they try to pass. They do have an emissions test every year or so depending on the year of the vehicle, but it has been 7.5 years since I have lived there so who knows. I do remember that they didn't use to be very strict on the visual inspection, so basically as long as you passed the sniffer it was good to go.

So every one agrees that if I get my heads and intake ported or buy ported LT1 heads/intake it will give me just as much and add a LT4 hot cam? If I put the HotCam in I need to run 1.6 rockers? Man I have so many questions. I just want to make sure I do it right the first time. I do appreciate the help from all of you. Peace

I wouldnt but just the hotcam itself. The deal is too good to pass up on the whole kit. If you buy it separate, you will end up paying way too much. The whole kit costs like $450 but for example if you buy the rockers by themslves, they are like $300, the cam at least $150. So just but the whole kit. If you want to hear a hotcam LT1 car, you can listen to mine when the damn tranny comes in. To give you an idea it sounds kinda like a B-cam in a 5.0. But I have mine mail tuned now so its hard to tell I have one (yes, I am being sneaky:) )

I am sure with a good tune you will pass any emission test with the Hotcam.

Sweet, thanx. I think that is the way I will go then. Ported LT1 heads/intake and HotCam. Come see me at a race near you in the distant future, Ha,ha,ha. Like I said as soon as I hit the states in August it is ON. So enjoy beating me over here while you can:) Peace Mmmmm...Beeeerrr!!

Well I am trying to get to AZ for my next duty station... Dont think you will get away so easily:)

That would be cool if you got AZ. I am truly doubting I will get AZ for my next base, but I only have 1 year and 9 months left in the military after I get back to the states. So it won't be to long before I get to AZ. I will be trying to get the car done before I move there.

Go LS1!!! However if you decide LT4 is the way to go you would be wasting your money. Because the stock setup made 330HaPees. You would need a stage II LT4 Head & Cam setup to touch 400. Just my .02 worth but sounds like fun and easy to beat you and I will be @ the races this year. Maybe I could take a nap at the lights to make it not so bad. J/K I will put $150 on the Hawk.

Been sniffing the 93 octane again? Once again for the slow people. The stock LT4 didnt use the hotcam. Unless being the king of the Dyno queens is important it will be more than enough to run the numbers.