LT1 to LT4 conversion

[SocalSS]

A buddy of mine just bought a 94z and wants to upgrade. I have heard a lot about the LT4 conversion so I figured I would ask the pros on this one. What are the hp gains? And where is the best place to buy the full conversion. Thanks for the help. Ryan.

[86RedRocket]

pm 95formula. He uses the lt-1 heads, intake, and a different cam that puts down a lot more hp than the lt-4 package will.

[Ryatt-Motion]

You can expect HP gains anywhere from 375-425 HP, depending on which route you go. Some people just buy the heads and intake along with 58mm TB, and others buy the mentioned along with the LT-4 hot cam combo. The entire combo is the way to go because you have a system that makes proven power and is completely matched. The only other upgrades I would reccomend is the 58 mm TB, an aftermarket fuel pump with regulator, CAI and 30-34 lb/hr injectors and of course a de-screened MAF. For additional upgrades you can go with headers and a high flow cat and a cat back exhaust. All of these additions will maximize the power potential of the Lt-4 conversion and make one unstopable Camaro. Good luck..

[86RedRocket]

"Unstopable", I seriously doubt. 95 formula runs 11.0's on motor. I've never seen a camaro w/the lt-4 kit anywhere near that.

[FANTA-Z]

I would definetly go with a set of ported heads and a nice cam over the LT4 kit anyday. You will get more power for less money and it is proven all over the country. With the kit you get weak springs so if you ever decide to switch cams you will have to change the valve springs when you do it Im not saying that the LT4 head is not a good head at all but if you port an LT1 head it will outflow the LT4 stock head and you will have about 350-400 in your heads compared to 1500 or more.

[RymerC]

What I like about the LT-4 heads are those valves! Hollow intake, sodium-filled exhaust. sweet! there's a lot of fat cut out of the valvetrain there. That's not to say you can't buy Manley valves or something and grind them into stock ported heads. Anyone know if the lt-4 heads have less valve shrouding or anything?

[95 Formula]

In my opinion the lt4 "kit" is kinda overhyped. Like stated above. Even though the lt4 heads have more potential..unless your going with a big..high rpm, heavy breathing cam your never gonna see enough benifit to justify the cost. I say get a reputable head porter to do your lt1 heads. You come out much beter in the long run for way less money. A set of ported lt1s will outperform a stock lt4...hands down. As far as cams are concerned its all dependent on what you want to do wtih the car. If its a daily driver an all out effort is not going to work. Either way there are better cams out there than a hot cam kit. comp cams makes some good stuff or get ahold of thunder racing or joe overton and they may can spec you out something. They both have some good hydrolic cams making good power. If you have any questions I will try to help you if I can.

Tim

[camarokid95]

See the LT-4 will work for me because i will have a 383 stroker installed with a cam that is a step above the LT-4 hot cam. So thats why i had the LT-4 conversion. My idle is going to be very lopey. I had my motor professionaly built buy a racing engine specialist. FULL ENGINE BLUEPRINT !!! YEA BOY !

P.S. no one mentioned that you may want to have the LT-4 heads and intake manifold ported even more. Like i had. I will be gaining even more than a stock LT-4 kit.


My finished motor is being dyno tuned this week. I will post my results as soon as i get them this Saturday. See how you guys like these #'s.

The LT-4 conversion is like the LS-6 conversion for the LS-1. Even though the conversion is proven for high HP motors if "blueprinted" correctly by a professional, but people still deny it because it do's not prove good gain's if that is the only thing you did to your motor.

Formula95...what did you do to your motor and what is your HP out put ??

[95 Formula]

I have lt1 headed solid roller 355(spins to 7000 before I shift). Balanced and blueprinted. Made 436 rwhp through a 9" and 4.71 gears. I agree that there is more in a ported lt4 head over a lt1. But most people don't really have enough rpm or motor to take advantage of that. What I'm saying is that the 1300 to just get a set of lt4 heads and then have to have them ported to outperform lt1 ported heads. For most people the money is better spent on killer head work to the lt1s.

Put it this way..steve quinn just went 9.90 with a stock ported lt1 casting head. A long way from stock..but it is a lt1 casting.

[86RedRocket]

Thanks for the input on the subject Tim.

[BigJustinZ28]

lol everyone has a different opinion on hotcams lol , I have the kit and although I am happy with it , I have buddies with ls1 and one of him has just a pretty mild lingenfelter cam , cutout , long tubes ok everything but heads and gears and he tears me up. Leaves me thinking after all the Lt4 with heads and cam and rockers what the hell do I do now ????

[95 Formula]

you pull the heads..get them ported and throw a different cam at it.

[Ryatt-Motion]

O.K. enough of the bully-sh!t, with the LT-4 Hype!! Here is what I feel is a kick ass combo. A set of AFR 195 CC heads (Good for daily street) and a COMP hydraulic roller cam XR-282, a set of Childs and Albert forged I beam rods SRP flat top light weight pistons a beefed up fuel injection system with a CPC conversion or even a Fel-Pro kit. Guaranteed to make at least 485 hp, maybe even more because of the fuel injection. I have the same combo in my 67 and with smaller heads (185 cc) and a carburetor (750 Demon) makes this power on the dyno. If you really want more power, screw the LT-1 and go with a 406. JMO...

[86RedRocket]

Or you could just buy a a ls-1 and spend a lot less money and get more hp #'s from the get go and still have an everyday driver. I'm not trying to offend anyone. I've had both a ls-1 and lt-1, so that's the reason for my statement. A have a lt-1 vette also right now.

[FANTA-Z]

True Red but you can buy an LT1 car cheap right now and throw what you save on not buying an LS1 into the motor and walk away from the LS1. I understand what your saying and dont get me wrong I really love the LS1 but if we are talking about more bang for your buck you can go the LT1 route and have a stout car for not a lot of money.