Thoughts on MHS PI H/C and stock bottom end

[theterminator93]

Nice job Brandon! Looks like a fun winter project. Stage 3 upgrade? Lucky guy! Keep us posted

Man really makes me want some MHS heads and cams! Be sure to post more pics of the install

Well, finally started the teardown on the engine this afternoon... all I can say is it's a good thing I'm replacing the plugs and wires. The ones coming off explain a great deal about the strange behaviors of the car lately... lol.

Anyway, while I was examining the heads a little closer this afternoon I took a good look at them and compared them to the photos of the stage 3 heads I see on Nick's website (and elsewhere). I'm now almost certain I have stage 2 heads and NOT stage 3 heads like I was told. All the stage 3 heads I've seen have the air dam between the intake valve and spark plug hole ground back. Mine are untouched. I asked for a confirmation from MHS on the matter, but they never replied to my inquiry.

Oh well, no big deal - I got what I paid for. I'm just a little irritated about their saying to me that I got upgraded when in fact I didn't. But life goes on. Depending on a great multitude of factors, I hope to have it reassembled and begin tuning by Christmas.

 

[theterminator93]

Maybe he was able to get stage 3 performance without touching the swirl dam now? I wouldn't doubt he's better at porting heads now than he was a year ago, as he now offers Stage 4 heads. I think its better because you lose 1cc of volume with the laid back swirl dam. My stage3s checked in right at 40.5cc's at the local machine shop.

Well... got most of the disassembly done. I still have to get what's left of the oil dipstick tube out of the block (that thing won't budge!) then everything needs some serious cleaning. Maybe next week I'll have time to do a PTV check - I'm just glad to have the disassembly out of the way.

Here's a few pics of the progress...

Harness, intake, valve covers and timing cover removed.


Passenger side head removed.


Crosshatching still there after 136,000 miles.


Driver side head removed.



I suppose one way for me to find out for sure what I've got is to measure the valves. I know stage 2 valves are .5mm oversized, then stage 3 valves even bigger...

2021 edit: Here are a few more photos of the porting:

 

[theterminator93]

For the dipstick tube, clamp on vice grips and hammer them up from the bottom.

And get a lokar for the new one. The stock one's harder to put in than take out.

Thanks for the heads up - I'm going to replace some of the hard to get at parts (heater hoses, oil filter adapter gasket, etc.) and try and clean things up a bit before I tackle that dipstick tube. I've got all winter to do this thing - I don't want to start rushing and regret it later.

I'm still not sure about the motor mounts. I'd like to replace them but since I don't have an engine hoist I'm not sure how I'd tackle them.

 

[theterminator93]

A "regular" set of Stage3 heads will have 1mm oversized valves as of recently. Previously they were still only 0.5mm.

Floor jack + 2"x4" wood chunk + oil pan = no need for a hoist.

BTW do you use regular oil? Those heads look pretty grimmy.

Funny you mention the grime - it gave me a little bit of a surprise too. I use full synthetic, but I think the reason they look so bad is because I didn't change the oil at my usual interval this last time around, so the oil has more miles on it than it should/normally would.

 

[theterminator93]

What synthetic? What mileage?

The last oil change was 5w-30 Valvoline synpower with a purolator filter at 130,000. I usually change ever 5,000 - but since the car sees about 5,000 every year I have settled into the habit of changing the oil every spring before I start driving it again. I parked the car at 136,000.

One other thing I should note is the car would lose about a quart every 2-3,000 miles - and to make up for it I'd add whatever I had available. The first time I added a quart it was the same stuff. The second time I have to admit an awfully stupid move - I didn't have any fresh oil on hand but I had just changed the oil on the Mark VIII - so to get me through the last month of the driving season I added about 1/2 quart of that.

 

[theterminator93]

Nice thread!

Man, that engine looks dirtier than the one I broke in the Red Cougar.

I bet the lifter galleries in the old heads are full of sludge, like mine was.

That stuff doesn't seem to dissolve, so maybe it will stay out of your new heads.

But I'd recommend 5W-20 Synthetic for the new heads.

Judging from the crosshatching in the cylinders, the lower end is in good shape.

Time to start looking for an explorer or Teksid block to build... You'll want a blower next.

Thanks! Yeah, it is pretty bad. The more I thought about it I came to remember that my dad has this terrible habit of buying the cheapest conventional oils he could find, often had irregular oil change intervals (5-8,000 miles or more!) and used Fram filters. He put the first 18,000 miles on the car and I think the oil was changed three times in that timeframe.

Now that I look back I think that's where all the sludge came from. I've been using 5w-30 full synthetic for the last 4 years.

I have thought about an aluminum block to get some weight off the nose. If I ever picked one up I'd build something with even an higher CR (closer to 11.5, maybe 12:1) with notched pistons alongside a bottom end to support 7000 RPM shifts. The rest of the drivetrain is capable, it's the bottom end and intake that's holding me back now. I'd like to stay N/A though.

 

[theterminator93]

just remember the more compression you give it, the more cam you have to give it to keep dynamic compression in check, otherwise you're driving right into ping-city and you can't leave without changing cams. Always look into that relationship.

Great pics Brandon! Looks like its coming along nicely! Keep them coming!

Any chance of getting a bullit intake or the old SVO intake after the heads are on?

Yeah, if I ever decide to go up with compression and RPM I'll definitely need a new cam. I'll have to do some reading on the topic of higher compression motors, I'm not very knowledgeable. But, I haven't even finished this build yet so who knows, I may not ever go that route.

As for a Bullitt or SVO intake... it's going to be something where I'll need to decide I want to go that route if I can even find one available for sale. I don't know much about them so I'd need to find out what is required for installation and whether it will clear the stock hood. I also need to find out if it will complement my existing setup for the purposes for which the car is being built.

I'm going to take advantage of the mild weather this weekend and replace the motor mounts, heater hoses, oil filter adapter gasket and lower radiator hose. I also want to clean up the front cover real well and clear-coat it. Once that's done I can start checking PTV clearance... after which I'll bolt up the heads and start putting the puzzle back together.

 

[theterminator93]

You'd probably be better off with the TFS street intake if it is even available (not the track heat). Most Bullitt intakes are $400+, and SVOs are rarer than hen's teeth--and I sure ain't giving mine up.

I'd like to stay N/A as well; and the high compression is a big part of that.

Not knocking your engine; you got the most worrisome pieces swapped out already.

Dino oil is good for mains, the ones in the Red Cougar were still barely in spec, but there were marks from debris.

I used seafoam and even kerosene to try and remove some of the grunge when I first got that car; the oil always came out black, no matter how long it was in the car, lol.

Never thought you were.

I really want to get it that bottom end cleaned up though. Thankfully the heads aren't a worry...

Now that I think about it, what kind of interval should I run on the first oil change? Would 500 miles be too much? I'd like to add 1/2 can of sea foam to the oil for the last 100 miles on the next two oil changes to try and clean everything out as much as I can.

http://www.summitracing.com/parts/tfs-518l0001
Dang, that's pricey. I sure won't be upgrading to that in the immediate future!

I was having a short word with my dad the other day and he suggested that I clean the carbon off the pistons before the new heads go on. I'm a bit concerned though with the best way to do it since I'm not taking them out. I was thinking to rotate the assembly to get a pair of pistons at TDC and clean them off so no pieces of carbon get stuck in the ring lands. Then there's the question of abrasives/solvents...

Any thoughts on how best to do it, or should I just skip it?

 

[theterminator93]

Vacuum? The engineer I worked for used one when rebuilding the top end of his gen 2 SHO motor. Said it worked very well. Just scrapped off a little at a time.

Purple Power does wonders cleaning pistons - I've got proof!

You can, but remember, EGR is gonna dump some nice shiny new carbon right back on them in a couple months, lol.

Especially if you max out the EGR table in the name of better fuel economy.

Kinda what I was thinking... sea foam is probably an easier alternative anyway.

I guess I'll brush off the loose(r) stuff with a brush and call it a day.

 

[theterminator93]

Don't use a steel brush because scratches cause carbon to build faster than a smooth surface.

I'll use my nylon wheel scrubby brush.

Plus, the last thing I need is a scratch or ding in the piston top. Can you say pre-ignition hotspot? lol

All right, finally got to cleaning the deck surface so I can start putting things together. I was turning the rotating assembly over so I could clean the cylinder walls of any crap that got stuck above the rings, and I noticed there are little notches at the front of each piston, in the same place (all pointed forward). I'm assuming these are by design so the pistons are oriented correctly, but I'm paranoid because a few years ago I was fighting a bout of pre-ignition.

Someone tell me they're supposed to be there!

 

[theterminator93]

yup, they're supposed to be there.

Made some progress today. Got the passenger side cleaned up well enough to put the head on then did a PTV check with play-doh. With the lash adjusters not pumped up there's about .07" of clearance.

So I bolted the exhaust manifold to the head and stuck the new head in its place. It's not bolted down yet; I figure I'll do all the torquing when both heads are on. I still need to bolt the coolant mod pipe to the back of the other head and finish cleaning the block surface before it can go on, which I'm planning for tomorrow.

I think it looks much better attached to something than sitting on the floor.

 

[theterminator93]

that's not how a PTV check is done

I followed these instructions...

Modular Head Shop - Powered by Network Solutions.

web.archive.org

Those of you doing a head and cam swap or building a complete longblock for that matter would be wise to check for piston to valve clearance. It should be REQUIRED as I would never build an engine without testing the clearances and neither should you. It is very easy to make one mistake, and then have a bunch of bent valves as the result. To clay for PTV you simply get some PlayDoh or Silly Putty at the toy store, install a thin 0.1" piece of it over the top of the piston where the valves would contact. Install the heads with an old set of head gaskets, install timing chains like the real build up would have, rotate completely, and measure the thinnest portion of the clay. If its less than 0.030" and the last adjusters are not pumped up with oil you have a serious problem that needs correcting first. It is both a lot easier and CHEAPER to correct before you start the engine than after.

I had the head on with the old gasket, timed it with the new gear/chain and guides in place and rotated it a full 360 degrees.

 

[theterminator93]

Ah a handheld hacksaw, can't do a headswap on these cars without it lol

And drop the exhaust before final install. It's not fun trying to aim the head, the exhaust manifolds and dipstick tube with that obstacle in the way

I didn't put the studs into the manifolds, the plan is to put the studs in from underneath as I line everything up. If that doesn't work out... down it goes.

I think I'm going to take your advice and get that aftermarket dipstick tube. I need a break, lol.

that's better....in your original post, it makes it seem like you didn't put the chains on or anything, lol.

BUT....

Did you torque the head down with the old headbolts and the old headgasket?

Also, a true PTV check absolutely needs an adjustable lash adjuster to take up the lash between the follower and the cam lobe. That, plus if you didn't torque the head down, will only show up as more PTV clearance than there actually is. I'm just saying..

BTW, that is one nasty oil pump, lol.

Yeah, old bolts and old gaskets. And tell me about it, the whole thing is super grimey. I'm having the front cover blasted then I'm going to clear coat it. I'm thinking I'll run 200-300 miles on the first oil change with a little ATF to help clean things up inside. I was thinking about upgrading the pump, but after some reading I figured it wasn't worth it. Eventually I know I'm going to end up with an aluminum block to build....


Got some more done today. I got the other head on and torqued them both down, as well as set up the timing gear and checked to be sure everything rotated freely. Also got the exhaust hooked back up to the manifolds, got the EGR tube in, put in the plugs and bolted up the DPFE sensor/bracket. I need to send the crank gears off to be welded as well as get some heater hose fittings so I can plumb in the coolant mod before I can do much else. Depending how soon I get my gears back, I can probably have this thing in the tuning stage by the end of the month.

Here's a picture... though it's not like you guys haven't ever seen a 4.6 assembly before.

 

[theterminator93]

Nice! didn't have to take the exhaust down after all.

Nope, it was a piece of cake getting the heads on without having the studs in the manifolds. Putting the studs in from underneath was a breeze too. All that's left for me to do that's under the car is get the new oil dipstick in the block, change the speedo gear, put the new tips on the mufflers and tighten the EGR tube/exhaust nuts.

Nothing to see here, folks, move on... move on...

Got a little bit done yesterday. Put the new dipstick tube in, plumbed in the coolant mod as best I could since I goofed on the angle of the pipe at the back of the head ... then I put the intake back on. Waiting on the timing cover to come back from being hot tank cleaned and for my welded gears to arrive, then I can make some serious progress on this thing.

 

[theterminator93]

Nice to see the plan coming together

And the final pieces to the puzzle!




I'm going to spray the front cover and bracket with VHT engine enamel clear to keep them looking like new, then when the crank gears get here next week I can get this thing buttoned up and tuned!

 

[theterminator93]

Nice, Brandon!

where's that notebook GM sent me to take notes in... *scratches around his desk*

ah got it.



bookmarked to refer to if the financial committee approves the proposal set forth this a.m.

Got about 75-80% of the reassembly done today. I did more after taking this pic, but all that's left is spark plug wires, alternator, belt/PS pulley, radiator fan, intake tube, tighten exhaust bolts, and fluids. Should have this thing running by tomorrow evening.

 

[theterminator93]

Congrats! Bet you can't wait for a nice day to take it for a spin! you should post a video of it!

I've forgotten, do you already have a tune for it? Or will you be putting it back on the dyno?

I've modified the last tune for PI heads and 30# injectors so I can get the thing through emissions, then I'm going to tweak it further once that's behind me. I got my wideband the other day. What kills me is the fact that I have to DRIVE it so it will complete the drive cycle, then DRIVE it to the emissions testing center, so I'm stuck waiting for a break in the weather when the roads are dry and salt-free. Which really, really stinks because we just ended a spell of low-60s yesterday... Highs in the teens and 20s for the next week.

Speaking of which, is there any way to check the OBD-II monitors for which tests it's completed/waiting to run with the XCal2? I remember I tried a couple years ago to no avail.

you did get my PM about the orientation of the crank gear right?

Yessir!

 

[theterminator93]

looks purty man. Hope all goes well with those last few steps and you have no "oh **** what is this!" issues. (dad and I always used to end up with one bolt that neither of us could remember at all nearly 60% of the time...)

in maniacal Dr. Frankenstein voice

It's alive! It's alive!

Not the greatest video... you can hear the squeaky mystery pulley more than the exhaust, when in person it's the opposite.

Holy crap I am so glad that part is done.

Now I have to dial in the AFR and clean things up a bit... oh man. FINALLY!

 

[theterminator93]

Awesome!! Sounds bad ass! Can really hear the cam in it.

wow, was actually expecting more cam lope than that. Sounds good though.

this can only mean one thing.....I can tack weld like a mo-fo!

Well hold on, hold on... I haven't hit 100% load at 6000 RPM yet!

 

[theterminator93]

wow, was actually expecting more cam lope than that. Sounds good though.

thats how stage two cams sound in our 4.6s in our cars.

Well hold on, hold on... I haven't hit 100% load at 6000 RPM yet!

who gave you that fantasy? lol

Hey, that's a "6", not an "8"...

Oh wait, math teacher terms.

36^(1/2) x 10 ^ 3, not 64^(1/2) x 10 ^ 3.

Although.............















My engine spins faster than yours does!

At least, for now.

 

[theterminator93]

might be possible if you had a real intake manifold. You'll likely top out in the mid-90s around 5000.

Parade rainer-on'er!

Party pooper!

Yeah, that sounds about right. I'll probably be content with whatever it ends up doing (for now). My wallet hurts too much already as it is.

Plus with this being my primary DD in summer I want to keep at least SOME driveability with the RPM down under 3000, so shifting the powerband up and up just isn't what I want to do. Also with this being the stock bottom end, I really can't shift it up any more than it already is without wasting power by virtue of being unable to shift at a high enough RPM to take advantage of it.

Once I get this thing's tune dialed in I'll be interested to see what the new numbers are - and if I made it close to my 280-290 RWHP goal. In all honesty I'd be happy if I made it to 270, but I guess the ultimate success will be how often the thing puts a smile on my face when I hit the go pedal.

Ugh, not being able to drive the thing until April is going to drive me batty!

 

[theterminator93]

That is a long time man.

GM;
I understand but for something stating stage 2 it just would seem more lope. I also know that lope is no indication at all of performance. You can have the lopiest sloppiest cam in the world and make less power than stock... But everybody likes a little lope at idle after you spent ~2k on heads/cam. It's part of that woohoo i have something not stock. Then again I also watched on a laptop. So I could be completely wrong and it has tons of lope. I just couldnt hear it.

Yeah, get some headphones or something with more low end to them - even though I did make the recording with my phone, it still comes through pretty well. Though like I said before, it has a LOT of rumble in real life where you can barely tell from the video. Plus it has relatively quiet mufflers on it too. Personally I love how it sounds. Enough lope to know it's got cams, but not so much that it bounces and shakes at idle or screams "race me!".

I will be making a new video of this thing with sound using my Sennheiser MKH20 studio microphones in the near future... Same as what I used when I did my first exhaust videos.

 

[theterminator93]

Nice man.

Got my first OT check of the year. I asked the wife if she wanted furniture. she replies. Did you not want parts for the car? I lurve my wife. So long as it is not 35 this afternoon I am going to see if the local Upullit has some parts. (mustang seats, rear diff 3.73 locker or even 3.27 locker, some trim bits, PBR brakes)

check wont afford Stage 2 heads though. looking forward to that video.

eah, get some headphones or something with more low end to them - even though I did make the recording with my phone, it still comes through pretty well. Though like I said before, it has a LOT of rumble in real life where you can barely tell from the video. Plus it has relatively quiet mufflers on it too. Personally I love how it sounds. Enough lope to know it's got cams, but not so much that it bounces and shakes at idle or screams "race me!".

I will be making a new video of this thing with sound using my Sennheiser MKH20 studio microphones in the near future... Same as what I used when I did my first exhaust videos.

Same here B , I believe that you and I and Joe are the only ones here that like the deep rumble of the Super Turbos , I have had my fill with loud ass mufflers in my lifetimeI ever have had something that's loud that screams "Look at me Please" Your project looks and sounds good

Yeah, I know I'm among the minority that prefers a quieter exhaust, which is strikingly apparent when I take the car to shows. I like to be able to hear my stereo without cranking the volume, plus I don't want to draw unneeded attention to myself through excessive noise, since, after all, this is my DD.

I really got lucky with the mufflers. When I was planning the exhaust I was looking at the Super Turbos online, then when I asked my dad what he thought about them he was like, "Oh, like the ones I have in the garage? I had them on my car for a while." Right diameter inlets and outlets and everything. Instant score! Free mufflers.

psh. Dad's 911 wakes up the neighbors... Perfect for disputes, but you race the car b/c of the racy exhaust...

The Thunderbird, to me, is a touring car. I want a rumble and that is about it. With enough lope at cold idle to let you know she's got a strong heart. (Despite the faded paint)

speaking of which. guess I'll head through termi's past posts and look for those videos he mentioned.

Put straight pipes on it and you will hear the cam

I got straight pipes on mine minus high flow cats.. good lord its loud! Last week I started my car up next to a 2010 camaro and a fairly new beamer both car alarms when off I wont lie tho secretly I was grinning ear to ear

Oh undoubtedly yes, it would come through a lot louder. The other car in the garage is my dad's 76 Trans Am with a 455 block/428 crank pushing 550+ bhp n/a. When he starts that thing you can hear it 1/2 mile down the road, even before he pulls it out of the garage. A little loud for me...

Sounds similar to my Stage 1 VT cams/Non ported PI set up.

Good job with it. Very interested to see how it runs and what numbers it can put down.
That thing should really sound good up around 6-6500 RPM LOL!!

Thanks Steve. Yours does sound a little similar, most obvious difference there being yours is a lot louder than mine! The idle sounds a lot smoother too. I'm also really eager to hear how it sounds when I am able to open it up some, and when I take it back to the dyno to get some new numbers.

Still got a few loose ends to tie up on the car before I consider this winter's project list completed. I swapped in my spare speedo head since the old one started going bonkers and I moved the lighted cruise switches over to the new steering wheel so both the cluster and wheel need to go back on before the car is going anywhere. I also plan to have the fold down seat reupholstered with some spare fabric I got so it matches the rest of the 97 interior. Oh, and I have to finish cutting and installing the new stainless tips I got.

GM;
I understand but for something stating stage 2 it just would seem more lope. I also know that lope is no indication at all of performance. You can have the lopiest sloppiest cam in the world and make less power than stock... But everybody likes a little lope at idle after you spent ~2k on heads/cam. It's part of that woohoo i have something not stock. Then again I also watched on a laptop. So I could be completely wrong and it has tons of lope. I just couldnt hear it.

Put it on some real speakers and you can hear it slightly, but I know from experience it's MUCH more pronounced in real life, having had stage 2ish cams in the past in my car.

 

[theterminator93]

The first vid was with the pipes running all the way back and the flowmasters on 2 1/2" to 3" to 2 1/2".

The second vid is the same engine set up, Bullitt Race mufflers, X-Pipe with 3" pipes and side exit exhaust to front of rear tires.

Its really not that loud but throaty. Boy does it sound good spinning at 6000 RPM LOL!!

Trust me, you'll like the sound of yours at RPM too.

And here's the video made with my studio mics. Good speakers or headphones recommended!

 

[theterminator93]

Nice Vid!

It sounds very good to me!

That sounds a lot like Lazarus; yours is a bit smoother because of the cats, I think.

My car has a bit of drone at 40 mph; happy I never drive there.

I wish it was a bit quieter; I'll spend more when this one rusts out; it was cheap.

With the stock 3.27s there was a little droning at 35-40. There was a good deal more drone at 60-70 though. After I put the 3.73s in the drone at those speeds virtually vanished. Something else I noticed was that without tips on the mufflers the sound inside the car was a good deal louder than with tips installed. I'm pretty happy with the overall sound levels inside the car now though.

 

[theterminator93]

alright, used somewhat better headphones this time. Man does that sound good.

also, that has to be the best sound sample of a vehicle I have ever heard. No wind blowing on the mike, no overloading of the sample by the car being too close. You could hear birds tweeting away and the exhaust. Not kidding when you said studio mikes.

It sounds great and thank you for posting what you did. Because i was going to do the same thing and what was done i was going to ask. Thank you for the post it answered what i was going to ask about the bottom end. thank you for posting what was done it sounds great

Nice job Brandon, she sounds great. All that hard work is putting out some nice notes.

Thanks!

For the heck of it, here's the finished engine bay.

It's all stock, I swear!

 

[theterminator93]

All righty, I'm just about satisfied with the tuning and I think it's at a point where it's safe... so I've made my dyno appointment for tomorrow at noon!

I won't be putting down any crazy numbers, but I think I'm allowed to start my own "guess the numbers" game...

So, any takers? What do you think it'll make? Personally I'm hoping for 270+.

275 Rwhp 292 Rwtq

Ok "Termi"..

259rwhp 299rwtq

Good Luck!



Rayo..

266rwhp 295rwtq

287rwhp 310 Rwtq

It's all stock, I swear!

I see three things that are not stock. Two are black, one is red.

So, any takers? What do you think it'll make? Personally I'm hoping for 270+.

Cams, Injectors, tune, exhaust... I hope you bust 300.

That's my guess 300 hp, 310 tq.

272 rwhp 299 rwtq

Reward??

Edit I forgot your torque was so high last time on the dyno. I change to 306 rwtq

Lol... reward... I'll send ten bucks to whoever gets closest. What can I say, I'm a cheapskate.

I'll pee my pants if this thing makes more than 300! lol

If it makes more than 300 your tuning mine! Lol

 

[theterminator93]

Welllllllll.... numbers are in.

290 RWTQ/255 RWHP. Less than I was hoping, but I'll take it. An improvement of over 20% from the old setup, and the thing is an absolute blast to drive!

I'll have to do some research to see what the next restriction here is since I know it's not the heads. I'm wondering if I've reached the point where the throttle body and plenum need some attention.

Here's the graph of the best HP run. I couldn't rev any higher because at 5800 RPM I'm close to 127.5 MPH in 3rd gear and I don't know of any way to prevent the car from doing a WOT 3-4 past that point. Looked like it was still putting down some good power up there too.

Rayo takes the closest HP cake, but The coop 08 gets closest on torque.

 

[theterminator93]

Dang I was for sure thinking you would hit 270 rwhp. Good numbers tho

Oh says 299 rwtq on graph you have 290 in your sig

That was just a spike on the peak HP run; the peak torque was another run.

 

[theterminator93]

What kind of dyno was that on? That don't even sound close to right.

The torque maybe but not the HP.

Didn't they have a way to lock the converter and lock 3rd gear to pull on out past 5800.

With that set up you should have been very close, actually better than what Stuckinkaos has pulled with his car which was right around 290 RWHP. You have nearly the same set up except you have more compression if thats the stock shortblock.

Just for example, my PI cammed PI Stock headed car pulled those numbers. See my signature. You have the same set up plus Stage 2 cams and ported polished heads. The only difference is my Bullitt intake. I'm not bashing you I'm just saying something doesn't seem right. Where were the AF ratio's on the car. Maybe the dyno was lying too. Regardless, if the tuning is right on the car the power is there no matter what the numbers say.

I've always been skeptical of dyno numbers. I believe in the state of tune and what it does on the road/track.

Still, a large improvement over what it did last time.

Exactly my thoughts.. Definitely not bashing but something seems off.

Your first dyno run was low on the hp side too. Is it the same dyno? Maybe its off?

I wonder if your 1/4 mile mph will show closer to 300rwhp..

Yeah, I agree with you both 100%. I was a little shocked to see how low it was too. It's the same DynoJet I took the car to last year where it dyno'd 212 RWHP and 280 RWTQ on a stock 97 engine tuned for 93 with PI cams/intake, underdrive pulleys and a 2.5" x-pipe dual exhaust. Their stopping the pulls at 5800 was per my request - I'm paranoid of breaking the trans on a WOT 3-4 and since I couldn't find a surefire way to lock out a 127.5 MPH upshift I decided to play it safe. I'll be datalogging acceleration to figure out shift points in the near future. I had my tuning laptop and XCal2 with me so I could have made adjustments between pulls but I didn't see the need.

The biggest thing I know of where others with similar setups have an advantage over me is headers. I realize mid-lengths would outperform my ported manifolds by 5-10 HP, but at this point I'm not quite ready to spare the expense to buy the headers, pull the motor to have them installed then have the exhaust cut up to accommodate them.

In addition I haven't been too aggressive with spark at high load/high RPM conditions. I just loaded the 93 octane PI heads value files for spark and went with it. In fact I've had to pull as much as 5 degrees of spark at 50-70% load at low RPM (sub 2000) conditions to prevent detonation. I also understand my spark up top looks about right for my setup so I'm hesitant to add any.

At this point I think I'm going to focus on getting the gremlins in the tune sorted out then I think I'm going to put my wideband back in and verify the A:Fs. When I was dialing the MAF transfer a few weeks ago my target A:F was 12.5 and I was within .2 of that consistently across the entire MAF transfer by the time I was satisfied enough to pull the WB.

At least it didn't ping on the dyno!