L-98 and the GM Hot Cam

[PBnf]

Will the hot cam from Gm fit an L-98. I have a 1990 coupe that I'd like to upgrade to that cam.

 

[SPANISHVETTS]

Yes but you should upgrade the valve springs. While it is apart a set of roller rockers would be a nice upgrade as well.

The hotcam moves the torque higher up and needs a lot more air than the TPI can pass. You will lose some lowend torque and never see much over 5000 RPM.

Unless you have a low ratio rearend you will give up some off the line acceleration while the engine works its way up into the torque range.

If your car is automatic with the 2.59 or 3.07/8 rearend the 1-2 shift will leave you behind the torque curve.

If you are not planing on modifying the intake there are better cam choices for the L-98.

 

[PBnf]

Thanks for you advice. You mention better cam choices for the L-98, what are they?

 

[SPANISHVETTS]

This is the cam that Grumpy likes and over the years he has been spot-on 100% of the time.

Ill second that CRANE 114132 suggestion, its proven to be a good 30-35 hp increase with zero problems, in many vettes over many years..its about IDEAL for a nearly stock TPI, engines power curve, BTW it LIKEs being matched with 1.6:1 ratio roller rockers, and DESPITE what it says in the instructions it doesn,t REQUIRE that 3.73:1 rear gear ratio, or higher fuel pressure BUT IT DOES work better WITH THEM INSTALLED, as it allows the cam to produce to its full potential

http://www.cranecams.com/?show=brows...32&lvl=2&prt=5

Before you start throwing money at the L-98 make up a truth table of were you are - where you want to be and how many $ you want to spend.

The L-98 is limited by its intake and exhaust. Until you open up both ends there is little that you can do in the middle that will net a seat of the paints gain.

If you haven't installed headers yet you should consider a set of long headers and a free flowing exhaust. With the stock exhaust I do not think that you will gain anything you can feel with a new cam. (eBay headers +/-$200, 2 X Hi-flow cats $99 ea. a bit of SS tubing and some muffler clamps $75 = Net Gain 30+ HP... That is a lot of bang per buck.)

If you want to build a torque monster that shreds tires and rattles windows you can port the TPI and be happy but if you want to see the tach above 5000 RPM then a new intake is required. Thunder has the big-mouth base with large runners and 52MM TB - all ported and polished to the max. It still runs out of air long before 6000 RPM... But it has more torque at 2500 than an LT4 at peak... I do not even notice the deep 1-2 shift of the TH400.

 

[PBnf]

Here's what I've done so far. I have a K&N air filter, and the frisbee removed. I also have muffler eliminators. I'm planning on installing Hedman Elites, long tube headers. Their 5/8" flanges, 14 gage collectors and ceramic coated for $378 shipping included. I'll put a high flow cat as well. I'm thinking of making it a true dual exhaust. I've been looking at the Big Mouth manafold too. Then I want 1:6 to 1 roller rockers and the cam. The car spends 99% + below 4000 RPM, so that's where I want the power. You're really I good source of information. Many thanks.

Paul

 

[SPANISHVETTS]

Keep an eye on eBay. A lot of the F-body hot-roders are trading up and selling off their L-98 bits. I picked up my intake for 1/4 of the list price.

You should PM Grumpyvette. He is a wealth of knowledge and always willing to share. Do a search of his post and you will see why I put so much faith in him.

Keep us posted on the progress.

 

[Dirtfarmer]

Good info Spanish.

 

[Lucky7]

If he's got a 90, it's a roller cam motor. If I'm not mistaken, that cam is a flat tappet. But I could be wrong.

 

[PBnf]

I don't know about the cam, but I do have a 90 and it has a roller cam. The Summit catalog has the Crane cam listed as being for computer controller vehicles. I would think it would be a roller. I was looking at the Lunati cam listed as 213-int. 219-exh with 454 &468 degrees of life at .500. Anyone have any thoughts on that. It seems to be about the same as the Crane?

 

[Achilles]

The 114132 is a flat tappet cam. But I'm sure Crane Cams can recommend a similar grind for a roller block. I would call their toll free tech line and ask. I have the 114132 in my '86 and think it's great.

 

[SPANISHVETTS]

The 114132 is a flat tappet cam. But I'm sure Crane Cams can recommend a similar grind for a roller block. I would call their toll free tech line and ask. I have the 114132 in my '86 and think it's great.

you are right. I did not follow the link... I though that I had picked it up from a different thread.

Talk to Crane about their Power Max X series cam kits. They come with everything needed in one box.

The TIPS Z10 might be a good choice as well.

Lingefelter used 211/219 duration at 0.05 and 0.505/0.525 lift w/ 1.6 rocker arms for his 350 street engines and those were built with Corvette aluminum heads.

Is the water muddy enough yet?:L

 

[Mad-Mic]

get the ZZ9 cam from TPiS or the Lingenfelter 219 cam and be done with it

that hot cam is junk and you are only looking at 20 more hp if that.