Let's start a new thread...

Bruce W. had the opportunity to run his '93 LE conversion (pictured in my gallery) last Saturday on the dyno. The plot below shows last weekend's results as well as the results from exactly a year ago when the car was in it's "stock" MRM306 condition. When first built it had a blueprinted and balanced bottom end bored over to 306, an E303 Ford racing Cam, a Lincoln MkVII 60mm intake and throttle, a standard Mustang Mass air tube (about 40mm), "worked" E7 iron Mustang heads, a stock 1991 Ford Mustang ECU and 19 lb injectors. Last summer we upgraded the heads to aluminum AFR's that my father did his head voodoo to, the injectors to 24 lb units, the intake to an Edelbrock Performer, the throttle to an Edelbrock 65mm unit, and the Mass Air sensor to a 72 mm unit. The results are as follows:



-Jason

 

Bruce, anything you want to add?

-Jason

 

THIS CAR KICKS ***!

But seriously, my goal is to clear 300whp and I think we'll be right there after a performance chip and tune. It's still on the stock Ford Mustang ECU right now. There are also some other minor power upgrades that we could do after that, but they won't be a priority for me. I will be keeping the car normally aspirated for the foreseeable future.

 

So you think it was running a little rich before the dyno day but is now good after the fuel pressure/timing adjustments we did?
-Jason

 

I believe it was running lean before the dyno day. Your father indicated to me when I was at his dyno that these engines like running at about 11.5:1 AFR. That seems pig rich to me but I'm not an expert.

I also think we could have gotten a little more power if we'd kept bumping the timing while adding in more fuel. However, we were pressed for time so I'm very happy with where we ended up under the circumstances.

The goals for me at that dyno were to make sure the tune was safe and to vindicate the car to the turbo guys that had seen the previous dyno plot. We accomplished these goals.

 

Here's my Stock LS2 crate engine numbers, back in November with around 1000 miles on it. I'm going for a custom tune after about 5000 miles. I read your posts and agree with most of your conclusions Jason, except your Ford Heavy ones pertaining to Motors. In all fairness my comments will tend to be GM Heavy as my primary experiences come from personal hands-on with more than 100 LSX motors ranging from stock to twin-turbo, inter-cooled.

Look at my stock crate motor LS2 numbers, headers and K&N only. NOW allow me the same indulgences you hand with the Ford, Bigger Injectors, Racing Cam, AFR Heads, my additional Port Magic, and basic Blue-printing & Balancing and I'm "reasonably" at 600-650 HP "Streetable" agreed? 700 HP GTOs and Vettes are common in Phoenix.

For discussion, the Ford Does in Fact enjoy great cost advantages for the V8 Miata, but the LSXs have a much better stock, starting point, performance profile and can be taken to Greater HP Torque numbers without as much Radical Modifications and their direct impacts to reliablity on pump gas for performance / street applications.

My opinions, and Heavily GM influenced.

- Lee

 

Lee, I totally respect your opinions and do admit to being a bit "Ford heavy" when it comes to mine. You're right, I can't argue that a modern LSx is a more potent starting point than a stock early-1990's 5.0 would be. It is. A stock Mustang 5.0 made 225 hp at the crank, an LSx makes twice that. If one were given the choice between a "brand new" crate 5.0 and a "brand new" LS1 or 2 for the same money than yes, the LS would be hands-down the better choice. What I'm saying is that while it's pretty difficult to build a 5.0 to the "potential" of a LSx it is relatively easy to build one to match or at least get close to the stock output of a LSx for less money than a stock, new crate LSx. From that point of view (again, I know I'm a Ford person...) the 5.0 still seems a better value and not worthy (yet at least) of being discounted as worthy of being swapped in a Miata.
Again, this is all contingent upon the 331 we're building being as potent as we hope. If it can hit LS1 RWHP levels my above statements are valid. If it can't, well, Lee I owe you a beer or something...

My opinions, heavily Ford influenced,
-Jason

 

NO don't get me wrong Jason, WE'RE GOOD!

I would have never even entertained doing a V8 Miata if it weren't for my two Ford Monster Miata buddies and riding in their cars. I have always respected Ford after building two Cobras and a Datsun 240Z with a Hi-po 289 Ford. I like 'em. I was simply drawing the V8 Miata comparison.

Also, a crate LS at around $5800.00 from a GM Dealer eluded my budget too, but having a Kid in the LSX engine business enabled me to score a New LS2 as one in a 12 engine buy (Cost).

I respect your thinking and you're right, the Ford's a great bargin

- Lee

 

I totally respect the LS conversions too. They put down great numbers, no doubt. If it were just about the numbers for me, I'd probably be looking to get into an LS conversion or at least supercharge my 306.

Having said that I find it a bit hard to believe that it's that easy to get 600+ whp in a normally aspirated streetable setup from an LS2, but I'm no expert. Do you have any examples including specs? The dyno plots I've seen have all been around (a very healthy) 450 whp.

One thing I like about my setup is that every modification Jason has done has been relatively mild in terms of affecting the car's streetability. There are only two minor drivability issues caused by the mods: it doesn't idle well until driven a block or two and it doesn't cruise well below about 1700 rpm. I'm confident a custom tune will solve the first issue, but already the car feels more "factory" than any turbo or supercharger setup I have driven.

How far do you plan to take your LS2? Because the other thing I wonder about is how much power in the Miata is too much. Maybe it's blasphemy in a forum like this, but I'm already having traction issues. I can't imagine how anyone could even take advantage of more than about 400 whp in a Miata until 4th gear and that's not very useful on the street. On the track, maybe, but then you've got the cooling issue to think about.

Just my 2 cents.

 

BRUCEW, just a quick note about how much HP is too much in a Miata. I used the GM 376/480 in my conversion. New, it dyno'ed at 415 hp and 430 ft lbs. (on 91 octane and at 5,000' MSL) 1st gear is somewhat useless under hard throttle but it hooks up pretty good in 2nd and on up. It pulls very strong and steady, from idle, all the way up to red line. It idles OK but I notice a lope when I stop at red lights, I guess because of the cam that GM uses in this motor. Currently I am running Toyo 225R16 T1R'S and they do pretty good. No cooling issues yet and we've been thru a summer in Louisiana. I'm pleasantly surprised about how streetable it has turned out to be and how well it handles. I'm going to put about 3,500 miles on it and see if I can get anymore out of it with a fine tune. Mine is just a fun street car, no track time yet. It's great sport to surprise Corvettes. No LS3 buyers remorse yet. Just my results so far, WIZ.

TOO MUCH IS NEVER ENOUGH! (HP, MONEY OR GOOD HEALTH)

 

Watch for yourself. Normally aspirated 650 HP LS2 on 91 octane pump gas. 600 HP's Easy with LSX. Lotta Great LSX Tuners in Phoenix too, Jim at Arizona Speed & Marine for one. UMS and many others.

Info resource

http://www.ls1gto.com/forums/showthread.php?t=344952

Start adding up the numbers to take a custom nicely built Ford and add a Supercahrger and everything required to convert and you're in normally aspirated, low LSX HP and cost territory, not my opinion, just fact.

http://www.youtube.com/watch?v=iuswdMLeo54

http://www.youtube.com/watch?v=H2iqupkixzE

If YOU MUST; 1000 RWHP with a Blower in GTO http://www.youtube.com/watch?v=UvD_Brevbb4&NR=1

1200 HP twin-turbo GTO http://www.youtube.com/watch?v=YyiA6...eature=related

To show a few