HOT cam is not emissions legal for one.

Like I said just earlier this summer a guy BLASTED me for saying this, then ran it and started a thread about how badly it worked out. The peoplke who swear the HOT kit is wonderful are the ignorant ones.

What it is is a simple poorly matched well known all GM kit.

I say poorly matched because anyone who knows anything will tell you the springs are NOT appropriate.

The Full heads/cam/intake package is 425fwhp at best and these days it is pretty easy to pick a 400+rwhp package and copy it.

If you have your heart set on all GM parts it is choice, but if you are after performance for your dollar there are better ways to go.

Here is the link I posted above again.
https://www.camaroz28.com/forums/sho...d.php?t=567396
That is more rwhp than the LT4 package makes at the flywheel, same amount of effort to install, WAY better result.

 

I'll say it..... It won't work as well as a well-ported, well-thought out LT1 heads/cam package.

The stock LT4 heads only flow about 240-245 CFM, about 15% more than the stock LT1 head. In my book, that's not enough to support a healthy 383. If you aren't approaching 300 CFM, you're probably starving a well-built 383. The LT4 HOT cam looks OK in a 350. Put it in a 383 and its too small. Ported LT1 heads would make a much better choice, than stock LT4's on a 383.

And... the current LT4 conversion kit is not "all GM".... its GM + Edelbrock

The original "conversion kit" included the GM intake. Out of the box, it is IDENTICAL to the LT1 intake, except for more metal above on the top of the ports - but not larger ports. GM never finished the development project, and the LT4 intake does not match the LT4 head ports. It requires significant porting to support well-ported LT4 heads. The "new" LT4 conversion kit includes the Edelbrock LT4 intake. The tests and measurements on the Edelbrock intakes (at least the identical appearing LT1) show that they gave up plenum volume to provide the "air gap" feature.... not a wise tradeoff, for a large cubic inch engine.

 

It might not be certified as legal but is completely tailpipe/treadmill legal. Here's what mine did back in 2000. That was last time it was tested. It would easily pass the plug in test as anything can pass that with a tune.



I won't dispute that. When I tested mine when I bought it, they wouldn't support the lift. I sent them back and bought some Crane springs. I don't know if they changed the springs over the years but I didn't feel safe putting those springs in. That was back in 97.

 

I find it interesting that the only way you two can win your argument is to compare PORTED LT1 heads with STOCK LT4 heads. If we compare ported to ported it becomes a whole different story!!!
I'm sure you've seen this before. Almost none of the ported LT1 heads approach your required 300 cfm.
http://www.fierolt1.com/lt1_lt4_headflow.htm

Also we have these heads, which are probably being used by thousand of guys, which are based on LT4 heads not LT1 and are discribed as ideal for 350 to 383ci engines!!!!!
http://www.airflowresearch.com/sbc-l...c-104_108.html

As for the LT4 hot cam. at .525 / .525 112 LSA w/1.6 ratio rockers it may not be the best for an "all out" 383 but is still a nice streetable cam.

Not everyone wants an unstreetable Drag Racer!

 

Show me multiple cases of ported LT4s being better than ported LT1s. From what I see ported LT1s work wonderfully. For every case of LT4 heads working well there is at least a match for it with LT1 heads.

There is a LOT of room between the LT4 package and an "unstreetable drag car" like 100hp worth.

Two weeks ago we went to a BBQ south of Milwaukee and my wife took a NAP in my car, put over 300 miles on it that day, not exactly the drag car folks want to pretend it is. Depending what calculator you use based on performance my car is 390-410rwhp compared to the LT4 package 425fwhp. My car is no freak, easily duplicated if anyone cared too.

 

Glad to see you acknowledge that I won the argument

And.... that LT1-LT4 head flow comparo is so pathertically out of date that you should be embarassed to have even posted the link. Do you see AI, LE or TEA mentioned in there? Of course not. The chart is from 1998.

I've got very healthy ported LT4's. I bought them in 1999 when there was no AI or LE. They were good, but they cost me a LOT more than the quality porting people can buy today for their LT1 heads, with the SAME flow I have.

Also might want to read what I said. I said "approaching" 300 CFM. I did not say 300 CFM was a "requirement".

I'm running a "mild" 230/242 114LSA 0.590/0.590 Comp Cam. Its a pussycat on the street, and will pass NJ rolling emissions. You don't have to power down to the LT4 HOT cam to have a "nice streetable cam". Get real.

You lost me completely on the AFR's.... what is your point?

 

WOW! Now that's a blast from the past. I haven't seen those guys in years.

FWIW, we were all on the F-Body lists way back in the day. Met a few of them at Memphis over the years for the F-Body Event. Tons of fun, brings back a lot of good memories.

 

A Chev. magazine recently had a flow test on the recent generation of heads.This article might be helpful in the selection process.

 

IMO, there shouldn't be a selection process. AI or LE, period.

 

im a dinosaur, but i like my lt4 kit alot. been in the car for 5-6 years with a hotcam and an obd1 conversion. tuned out the egr and skip shift. the kit is super reliable and fun to drive. its a blast on the back country roads and gettin on the freeway. works for me.

 

heck stock intake stock lt1 heads cam only cc503 and go the same times as the entire lt4 conversion only reason i have LT4 stuff on my current car is because it came with it... this winter it is comming off and getting replaced by better gear.