My 1998 2-door build is done - Pics, impressions (and need some input)

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Toomanyhobbies

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So I have posted a couple times about my truck that I bought last September. I picked it up last Friday but I wanted to drive it a number of times to really evaluate before I posted. First the pics...

May 2018 2.jpg May 2018 4.jpg May 2018 5.jpg May 2018 9.jpg May 2018 10.jpg
I am very happy with the truck. The motor is a new L-31R with a ZZ4 cam some other goodies and a Black Bear tune. It has ebay stainless headers with an 18" Magnaflow 2 in two out full stainless 2.5" exhaust. It makes plenty of power and is as fast as you want to go in a truck (at least for me).

The interior consists of new carpet, NBS titanium colored headliner and seats from a 2010 Tahoe that are so comfortable compared to the old seats. Richmond Seat Covers was kind enough to make me a set of seat covers in Neutral so I was able to leave the rear seat alone because it's in great shape. I did Dynamat on the floor which I don't know why anyone wouldn't do. I replaced basically everything in and including the dash right down to the turn signal stalk and the light switch control. I will take a bunch more interior shots and upload them later.

The brakes are also great. It has a Little Shop MFG disk kit in the rear and a Powerstop heavy duty brake kit up front and an GMT800 Hydroboost from a 2003 Escalade. My mechanic did a beautiful job on the brakes and it stops like a BMW.

The suspension is a 1" crank of the bars in front, new leafs in the rear with 1" shackles and Bilstein 4600's. It's also great except the new leafs already have surface rust and I am going to paint them with Eastwood Antirust from a spray can. Anyone who cheaps out on Bilsteins ought to do the math on the incremental cost per mile on buying better shocks. They make such a difference. I also had a moog steering stabilizer installed not sure how much it helps though. All bushings and front end bits are new urethane.

The paint job, for what I paid for it, it great. The pics speak for themselves.


Here is what's less than great that I could use some input on...

The steering box is a Redhead 454SS box and it is very responsive on a truck that already has a tight turning radius. But the steering feel is way too light, lighter than my old stock '97. I took out the variable assist servo with that stupid U valve that is a $60 piece of metal and it has a brand new pump with the extra outlet for the hydroboost. Any thoughts to reduce the assist (and increase the effort in the wheel)? I could use some help here.

The trans is a "built" 4l60e that was done by a highly reputable shop. I paid a highly reputable price for it so to speak, which is another story. It has upgraded clutches, the 5 planetary gear upgrade, and a shift kit. What I don't like about it is it goes into 4th too easily and almost dodges 3rd on me both up and down. As in it will shift into 4th while I still giving it some throttle in 3rd, and if I step on it hard enough to kick down, it will actually kick down to 2nd at highway speed from 4th, at least briefly, before finding 3rd.

This is particularly important because the ZZ4 cam, while it has a wider range than some would say on the web, really takes off at 3K. But I have a hard time finding 3K on anything but the highway because I am going too fast for regular roads at that point. If the shifts were delayed somewhat and 3rd was a sticker gear the truck would run better. I remember reading somewhere that 3rd was the weak link of this unit so maybe it's set up that way on purpose?

The cold idle is bad, and it seems like there is unburnt fuel on startup and it will even die out sometimes. I turned the idle screw on the trottle body up so that it runs at about 925 when warm, but I don't think it makes any difference really because if it ran right when cold the computer would take over here. When I got it tuned Justin of Black Bear told me that the O2 sensors gave poor readings until they are warm, so the easiest thing to do seems like to replace them. The rears are deleted.

It may be too loud but I haven't decided yet. The 18" is the biggest muffler Magnaflow makes in 2 in 2 out so I may need to change brands. Suggestions here would be great. It sounds great at idle, like a Chevelle, but it's loud when you step on it and a little throaty in the low 2's which I don't entirely love.

I have a list of 27 little odds and ends to do to it to make it perfect starting with finding a nice set of Tahoe emblems for the sides and I am probably forgetting 10 other things. Any good recommendations on junk yards that have a lot of GMT400s and can mail parts to me would be appreciated as well. There are a lot of little bits I need.

More to follow.
 

Zdorf

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That is a beauty of a hoe!!!!! Took down all your notes. Thank you.
 
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Toomanyhobbies

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I drove the blue one for 5 days in a row, and then got behind the wheel of my 2004. It was like a timewarp from when I traded my '97 two door in for the 2004 when it was new. I remember thinking it was positively space age at the time. Now the GMT800 and the 400 feel way more similar than different when both are compared to the new generation of trucks.

I will say that they both have the 4l60e and the 2004 does not have the same adversity to 3rd gear that my rebuilt "built" '98 does so that's something I need to look into further.

The ebay LED interior light kit is a really great inexpensive touch for our trucks FYI. Really makes it feel more modern.
 
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Toomanyhobbies

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I have knocked out about a dozen little projects to the truck and probably have 25 more. I replaced the O2 sensors and that did nothing to smooth the cold start so it has to be a tune issue which I will get to eventually.

The hydroboost was leaking and now has subsided to very little.

I got a nice set of "Tahoe" emblems separately on ebay for about $36 a piece. If anyone has the measurements as to how far back they go from the front edge of the door I would appreciate it.

I am no longer questioning if it is too loud anymore, I like the way it sounds.

I took my first real road trip yesterday and today about 60 miles down to my hunting club in Delaware. It is pretty gutless between about 60 and 70 unless you kick it down at which point it usually screams into 2nd begins to hurtle forward. At 70 it's only turning 2K and the cam is not where it wants to be. I have a 3.73 rear and may have to go 4.11 to get it right but I am not doing that now. I also noticed that it was showing different RPM at the same speed depending on load. Meaning going up an overpass it would show as high as 2500 going 73 and on level ground it would show 2100. Does this mean it's not achieving lock up?

It's really fun to drive on 4 lane divided highways and country back roads the way it's set up though.

I settled on a valve to fix the steering pressure. It is WAY too light and twitchy, especially at highway speed. I will post it here later.

On the way home I stopped at the junk yard where I got my hydroboost pedal and got two new passenger A/C vents and already have them in and they look like new. Also got a vanity visor with the plastic tabs intact. Need to change that out another day.

A couple pics below. I will take one of under the hood and post it. I have been cleaning up the engine bay little by little...

At farm.jpg In Driveway.jpg new vents.jpg
 
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