Is a LT4 intake capable of 475 to 500 rwhp NA? I know everything must be damn neer perfect when it comes to the engine and heads. I know the motor I am building should be able to produce such numbers, but the intake is the BIG question mark. I would like to hear from someone with actual results.

Michael

 

michael,

i made 473 on a so so tune went 10.91, then tuned it myself with roman driving it and went 10.7. so yes it is very doable and that was on a camshaft geared for a bit of spray

 

That intake can support a good bit of power. Mindgame on this board is making almost 570rwhp NA with a 383 LT1. Bad *** 15* heads too.

 

Mindgame is not a very good example. I believe he used some sort of spacer to adapt the heads to the intake.

Taner,

You are giving me hope. I will be pm'ing you soon about the intake situation.

Michael

 

Mindgame is not a good example at all. He has adaptor plates and the motor is not your ordinary LT1 nor LT1 intake.

10.90's to 10.70's is doable on the LT1 intake OR BETTER DEPENDING ON TRACTION AND SETUP (obviously you can go 9's if you do open heart surgery on the intake), but also look at the mph it's usually 125-128 range. Looking at standard weights of drag F-bodys that shows it usually limits HP. That intake will limit the mph and the rwhp. Guys like Steve Quinn have modifed the LT intake extensively and can run more RPM and get more power, his mph shows that. Obvioulsy Ed Wright has a very good intake as well.

You can spend a lot on getting a LT intake to work or you can spend the same amount to get another intake to work better.

Bret

 

Well you didn't specify what heads I think it is a good example since the LT4 can support that much power, and you're looking to make somewhere under that. The spacers didn't add much length, probably no more than a 1/2" at best. Chuck said the LT4 intake was holding the car back about 30-40rwhp or so over a single plane. So it must be pretty good. Just my opinion, take as you wish.

 

the spacers and 15* heads had to have helped a wee bit

 

A local guy went 10.2's on an LTx intake @ the '03 Thunder Shootout. No idea what he dynoed (don't think he cares either).

 

I know, i know... just stating what the dang thing was capable of FWIW, i went back and checked, the spacers added about 1" to the runner length.
http://web.camaross.com/forums/showt...t=mindgame+car

 

I would kill for an inch longer intake plenum.

 

I know Ed Write has gone 10.1x now on his...highly modified intake

 

how about we list the things that can be done to an LT1/4 intake to make them better? There is welding above the injector to make the port taller. Would cutting the back part off and extending the plenum rearward help? How about cutting the top off and extendign the plenum virtically?

 

ed wright has been a best of 10:26@131 1.3x 60ft in hallsville,tx just a few weeks ago. and he has a LT4 intake on his now excatly what is done i dont know

 

from ed's post


My '96 TA made 474hp & 435tq. It's an NA 383", 4L60E & 4.30 Moser 12 bolt.
Best times so far 10.26 @ 131.72 1.312 60', at 600' DA

Those numbers are rear wheel, with a stock unlocked converter. 93 octane pump gas. Torque always looks stupid-high with the race converter in it. Wanted to know what it actually was, and at what RPM it peaked, so John & I put it on the dyno with the stock converter installed for initial run in & tuning. Easy to do when the dyno & lift are sitting right there. Rolled it back forward to the lift after baseline tuning it, and John put the race converter in it.

The heads are just GM LT4 head & intake castings ported by Pete Incado @ CNC Cylinder Heads, down in Florida. Nothing special, just his normal deal. Wish you could put big valves in them. Kinda looking at some other options right now.

Take care, Ed

 

I was making almost 480rw NA with an LT4 intake. Very little porting.

Jason