LT-1 to LT-4

[mike95z28]

alex gave me the idea of converting my LT-1 to an LT-4 and i was wondering if anybody knew where i could get everything i needed and how much it would cost and also where i can get it done cause im not gonna do that by myself...so any help would be awesome....

[GrandmasterCow]

http://store.summitracing.com/default.asp?target=eproduct.asp&N=120+4294925232+4294922130+305334

[Fastbird]

It's not worth it, and your motor would not be an LT4, merely a converted Lt1. LT4's had their own 4 bolt blocks too.

For the price that you're going to spend for the Summit LT4 kit, you could have a VERY nice head and cam package put together and blow the LT4 kit out of the water in terms of power and torque.

[mike95z28]

well what would be your suggestion? and how much would a difference in price and performance will there be?

[Fastbird]

Well, provided that you have a supporting exhaust system, ect, I would say talk to either Lloyd Elliot (search in LT1 Tech on CamaroZ28.com) or talk to Phil @ Advanced Induction. I know LE offers heads for $1300 and head/cam packages for about $1500, and advanced incudtion offers them for about $1700. Both of these guys have been getting consistent results in the 400+ RWHP range. GRanted, you'd still need new rockers, but the heads would be coming complete (springs, retainers, ect.). Pushrods, guideplates (if you went with a N/A rocker), gaskets, timing set would all need to be purchased, but if you played it right you can still be under that $2300 price tag of the LT4 getup.

The thing I don't like about the LT4 setup is the advertising, and the power for the money. They advertise 425 HP, but what they don't say is that's flywheel, not rear wheel, not to mention that it's a pretty optimistic rating too. Given a 15% power loss for the drivetrain, you're talking 361 RWHP. Not going to happen on a hotcam and unported LT4 heads.

Besides that, a ported set of LT1 heads will KILL a non-ported set of LT4 heads. Even when the LT4 heads are ported, the LT1 runs neck in neck with the LT4's until the .550+ valve lift range, where the LT4's will flow slightly more. The gross lift of the hotcam with a 1.6 is only .525", so then again the LT4 heads become a non-factor.

You could get a good set of ported LT1 heads for + or - $1300, a custom cam for <$400, new Pro Mag 1.6 SA rockers for $250, gasket set for $150, and a new timing set (pricing varies depending on year, Water pump used), and KILL a LT4 conversion kit.

[Squirrel]

Phil and LLoyd just have very good reputations for being able to wring a lot of power out of LTx heads, and youre paying for that proven power....but IMO any other reputable head man should be able to do it, a good(not the best) port job is still better than no port job at all :cheers:

[mike95z28]

u guys thinks you could help me find those other parts youre talking about online..i have a guy that can do the work for me i just gotta get the parts and since u put it at such a good prcie i could probably get this all done very very soon

[Squirrel]

theres always pairs of bare lt1 castings on cz28, probably pick em up for 150-200, gonna replace all the hardware anyway, so you might as well save a few bucks

[Fastbird]

Yeah, check CamaroZ28.com and Ebay for the bare LT1 castings. MAKE SURE THEY'RE THE ALUMINUM ONES. If you can, get castings from 92-94 as they're proven to have more metal around the key areas and produce slightly better results.

www.advancedinduction.com is one of the places I mentioned.

For the parts like the rockers, ect. www.thunderracing.com has very competitive prices and is EXTREMELY reliable to deal with.

Are you saying you've got a guy who is going to do your porting work or who is going to do the installation??