MTI was always a reputable shop years ago, they just sort of faded out of the LT1 side of things. Seem to be concentrating on the LSx motors like most other shops.
I would agree the flow numbers seem a bit optomistic but I am sure they are still good heads.
People here often have a hard time realizing that things are not black and white good or bad, best and junk. There are usually a number of genuinely good shops that can provide any single service or product. MTI was long one of those good shops and I never remeber reading anything bad. Just do not hear about them on this side of things due to the LSx focus they have had for awhile.

 

Im sure the heads will be fine for my 383 but it seems that alot of people agree that the 987 springs are as they say JUNK. The 26120 Beehives are the same height as the 987's but the beehives have a slightly smaller O.D. I can get a set of these with the retainers for about $200.

 

MTI is a very good shop but that has nothing to do with how heads now compard to heads done a few years ago. I personall know Jayson and Craig whom used to do the LTx heads for Jayson. Top notch people, but head technology has jumped 10 in the last 2 years alone.

Best analogy I know of is the first plazma tv's compared to the latest 720p or even 1080p. Are the older ones still good. Sure. Would you buy one now. Nope. For the right price?? Nope.

 

These heads were on a 96 Z28 M6. The car made 403 RWHP with these heads and supporting mods. Im not worried about the age of the heads. what worries me now is the springs. Would the 26120 Beehives directly replace these 987?

 

Im not having any luck finding out anything about wether the beehives will work.

 

Everyone's hooting on the 987's but I've had good luck with them in the past if your not running a ton of lift. Used to be what everyone was running at one time and yes; I know most people in the know, really don't like them.

 

Denney, trust me I understand that in just the last couple years a few shops have rewritten the "limits" of the stock castings. That does not mean older work is bad though, not everyone needs the latest and greatest. If they did what would those of us who constantly upgrade things do with our old parts?

On the springs I think what you are seeing is a shift too the newer technology there. These days everyone is looking to run cams more or less designed with the beehives in mind. The 987s work I would just not pit them against the latest aggressive cam lobes.

On fitting the 120s worst case scenario I think you would need different locators, not a big deal.

 

Most of the time it's the 918s that people are using if your going to switch to the beehives. And as far as the 987s go, I'm sure they work with some cams, but which ones they are I couldn't tell you. Anybody know the limits of the beehives as far as lift, aggressive lobes etc? Bret are you there?

 

They both have limits. Bret sent me an e-mail over the weekend as I'm running .630 lift and had issues with both the Beehives and the 987's at that lift. Need to look at my notes but Bret is saying there may have been a bit of confusion regarding installed heights and that may have been an issue with the BeeHives. Ended up with some PSI springs and really need to dyno the car to see how they are doing.

The 987's would last at least two weeks before loosing high rpm power at that lift and rpm (7200). As mentioned, they've been pretty good to me in the past regardless of a less than stellar image amoung a few people of knowledge. Less lift and less rpm presented no problems in anyway and I've seen quite a few others experience the same. The only exception might be Comp's Xtreme grinds as I never could get them to work for me.

Now heads...... I'd at least send them to a good shop to be freshened up and the porting tweaked if possible. Did exactly the same myself a couple of years ago on some LT1 heads that I had and was able to make 441 rwhp in a 383 with a somewhat mild cam. Taint great, taint bad, but I'd bet most would be happy with that.

 

Denny, did you ever get that monoblade to work or was the 58 enough for your hydraulic 383? Also, did you ever take that motor to the track? What did it run?

 

That particular 383 had a 58mmTB and I'm 100% certain the 58mmTB was more than enough. Never took it to the track so I have no baseline, but peak numbers can be deceptive. It's still average hp within the applicable rpm range and it probably would just done just so, so as it ran out of power @ 6500 rpm due to the heads/cam.

Ironically considering the topic of this string we upgraded my current 398ci to a monoblade for all the wrong reasons. We were going flat @ 6000 rpm and couldn't figure out why. Changed lifters, TB and springs. It turned out to be a 987 spring problem that was killing high rpm power vs not enough air getting in as the same issue came back very quickly. I'd never had spring problems before and didn't recognize the symptoms so we were throwing mud on the wall to see what stuck. Currently seriously doubting we need a monoblade now, but got one never the less.

Last summer took the 398 motor to the track for initial shakedown and burned up the clutch the second run. (That was a lot fun) For some reason wasn't getting the numbers considering the mods and didn't bother to return to the track as I don't like to run one unless I know it's 100%. Found a strange issue with a header hitting the motor mount that's been throwing off the tune. As soon as the weather clears and we clear up the issue, I'll see how the current combo does.

Kinda paid my dues on the track and don't do very much racing anymore so I'm kinda a dud in that sense.

 

The current issue of one of the car rags (damn this short-term memory loss!) had a beehive vs "standard" springs comparo where power was nosediving @6000 with the standard double springs. Billy Godbold of Comp explained that they were getting valve bounce at closing because the spring was in resonance ~6000 and couldn't control itself, let alone control the valve. Therefore the engine wasn't able to "trap" the air it was able to injest and power fell off a cliff. That's a good explanation, IMO., but Billy is a master at explaining things mechanical.

They changed to beehives with the same closed and open loads, and associated retainers, and saved ~54 gm per valve. Power picked up and the peak was the typical smooth non-peaky drop off. "Who would have thunk it?" was the tag line by the author/editor.

A lot of folks have been there, done that for a while now. It's good to see the car rag guys buying into it more and more. "It's not magic, it's just physics." to paraphrase Billy G.

 

Guess my problem is I didn't get a warm n fuzzy the first time out of the box with the Beehives that was later solved by conventional high quality springs. However, admit that it seems I've got the magic capacity to make more problems for myself, than I solve. We'll give um another shot to see what they do.

Need to revisit the issue, but it's gonna take a whole lot for me to start trusting what paying advertisers submit to the mags for publication. When they stop taking $$ for advertisements and having salespeople solicit vendors to place adds, my ears probably will perk up a little more at what I read in them.

 

I hear you on that Denny, same with websites... LS1tech.com would be the guiltiest party out there... because in reality they are the new magazines.

You can do the same things with Dual springs you can do in beehives it just costs a lot more money. PSI has a great dual spring thats small and light, problem is that just the springs will cost double what the beehives cost and that doesn't take into account the more expensive retainers you run with the duals.

Then again there are beehives that were used in Cup for plate motors that are awesome springs, but they cost $285 a set for springs alone. Then again retail on a dual spring that is of that quality and lift capacity would be $400+

The good thing is beehives aren't one of those things that are magazine fluff. If they were all the companies out there who didn't have them before wouldn't have made them and put them in their product lineup.

Bret

 

What's the phrase.........?? "How fast do ya want to go?"

Will it be the $$$ or the $$$$ meal tonite sir. May we suggest the $$$$ bottle of whine to go with it.