Forged bottom end get in here!!!
 

Just finished my 1.8 turbo setup, but its on a limited stock engine and is daily driven. Im in the market for building me an eventual replacement 1.8, not planned for but capable of being daily driven, but im new to engine building/planning and searching the forums has only gotten me so far, Ive looked around at different con-rod and piston combos, prices, "claims" of each products, and price comparisons between the products. What im looking for is suggestions from the experienced forged crowd.

Planning for,
MS1 Standalone (current engine management)
550cc injectors
190hp fuel pump
T3 .50 trim (current turbo)
99 head (unsure of cam/valvetrain combination, open to suggestions :bigtu:)
18-20psi with water/meth injection. 280+whp range is the goal :x:
83.5mm bore
8.5-9.0 CR (in this range)
ARP Fasteners
BEGi Intake Manifold
etc etc...

If my above hardware plans arent capable of such goals, do correct me and leave a suggestion!

Just really wanting to find out peoples opinions/suggestions on different rod/piston combinations that are capable of my goals and the legitmacy of each products "claims" of reliability and power as well as good price.

sounds feasible to me. put a dual feed fuel rail in there for insurance and you should have no problem.

I'm really interested in learning about the advantages and disadvantages of going with 84mm bore over 83.5mm other then slight displacement bump? Is a stock head gasket still compatible?

I am pretty sure that 84 mm is the limit that you could bore and use a stock head gasket. It is what I have, and the gasket appears to barely fit.

Another advantage of having a larger bore size is that the cylinder head flows better. There is a larger gap from the edge of the valve to the bore walls, so the air/fuel charge is not dammed up by the cylinder walls.

If you plan on doing any significant head work, with larger valves, I would strongly consider going to a larger bore size than 84 mm. Head gaskets are available for the larger bore sizes.

No plans for significant head work, simply a 99 head swap and simple deshrouding. New valve seals, and aftermarket valve springs and retainers and call it a day.

Carrillo rods, FM/Wiseco pistons, burn E85.

Aside from recommending larger injectors, if you couldn't hit 280whp WITHOUT meth on that setup @ 18-20psi I would have to say that you are doing something wrong. I made 235whp on that same turbo on a 1.6 @12psi, 20 psi on a 99' 1.8 should net you closer to 350whp+. To be honest, I'm fully expecting that with my new manifold/downpipe/exhaust I will be right around 250whp @12psi. You need to assess your tune.

What he said.

Your power goals are modest for the set up you are describing and you'll likely hit them under 18-20psi.

OP -> post your timing map for evaluation and ridicule.

:D

you have a decent list. You have a realisitic goal. everything sounds good. Now to assemble everything properly and then tune it all properly and you're set.

did you use the same dyno?

my 92 9000 dynoed 265whp and 330ftlbs on a dynoject, and then a few months later running the same configuration, it did 235whp and 286 ftlbs on a mustang dyno;)

Mine was on a dynodynamics, which by all accounts I've heard reads lower than your average dynojet.

coolant reroute before dual-feed fuel rail

If you plan to run the stock cam or a very small upgrade, I would not change the valve springs. Stiffer valve springs should only be used if they are needed to control a very high reving motor from a cam with a lot of duration and lift. If you have budgeted for valve springs, I would go with new valves with undercut stems instead, and ditch stiffer valvesprings. You will not need to fool with the valve seat (other than lapping) and you will get a little better air flow.

Stiffer springs will do one thing for you if you have not upgraded the cam. Rob Horsepower!

You may also consider using shim under lifters. They are much lighter than stock, and will net you a little more power.

Edit: Considering your goals, stick with the smallest overbore. We want to keep as many viable blocks around as possible at the rate we are blowing them up.

hahaha never can have enough good 1.8 cores floating around can we.

MSQ posted for your elegant but experienced ridicule! lol if I did not load the right file or did something wrong do tell lol, I've never just loaded a spark map alone to here.

I see your problem.

Your spark map:
http://lh6.ggpht.com/_tMYIeupe-9Q/S-...map_na8psi.JPG

My spark map:
http://lh4.ggpht.com/_tMYIeupe-9Q/S7...dynotiming.png
(Sorry for the shitty, uncolorized format)

Notice the curve it has? It ramps up during spool up, then drops down towards peak torque (to prevent knock) it then ramps back up to keep torque flat(ter) till redline.

Note: If you use this and blow your shit up, I hold no responsibility for it. This works well in my car, but I have reason to believe that other people might not be as fortunate.

Damn, I appreciate the insight. Definitely noticed the curve in the spark map now that its been pointed out to me, I've never had any experience with tuning or looking at spark maps. So I could definitely pick up some power on the big end with proper ignition tuning?

You'll pick up power EVERYWHERE with proper ignition tuning, plus have better spool = even MORE under the curve. Timing is the key to making power, but be careful, because more often than not it is also what kills motors when you get careless.

Jeff could I possibly steal a peek at your MSQ?

http://farm2.static.flickr.com/1151/...32871078ce.jpg

:giggle:

Granted, my motor is sitting on my garage floor and may be scrap, but not due to tune or fueling or anything...

It won't apply to about 99% of your setup because you have a 1.8. The relevant part is the timing map, which is also not entirely accurate because the VE curves of the two motors are similar, but not perfect.

http://i43.tinypic.com/vphpnp.jpg
that spark table is 6-8* back from MBT at 184kpa+(crappy CAS and headroom for heatsoak on the track) and made 254whp at 11psi, and like 305 or whatever at 16psi on a gt2860rs with an 8.6:1 compression 83.5mm bore. If I ever get a crank wheel I'll put that spark back in it.

Holy spark map! I see why hustler is god.

So, water/meth injection for my purposed setup would essentially be overkill for a car that will at most see the drag strip on weekends? Basically, that I should make my goal of 280whp+ on just the hardware of the setup alone, not using the methanol as an essential octane boost to grab more timing?! Im also intrigued to discussing what is a proper/efficient CR to choose from for pistons and the effects of said? Picking 9.0 vs say 8.6 will this essentially effect power under the curve, overall power capabilities, or what essentially does one take into account when trying to choose between the two? I've heard many a rumor of people ranting that lower compression is just an all around better choice when looking for peak power numbers vs say 9.0 CR giving you better power under the curve?

Guys, elaborate all help is appreciated criticism likewise. Anyone who contributes gets free beer! :friday:

No one who's driven my car around town made a mention of a lack of power in vacuum. FM stands by 9.0:1 compression, and even on Matt Andrews' car it works all the way up to 400+whp on the racetrack. I'm somewhat ignorant to how engines work compared to engineers but the low comp certainly gives me headroom and allows for a ton of spark angle. It wasn't a better choice for me on peak power...it was better all the way around or at least good enough for the large AR turbine and lots of spark.

For what I have learned, low compression really becomes critical when you are going for mega high boost. I always thought that if you had the ignition, ECU, and proper fuel to handle it, higher compression would make more power when boosting with lower pressures.

With my nitrous experience, the smaller shots made more power on high compression engines, but if you wanted to make the most power possible, a lower compression engine coupled with a very large amount of nitrous was the way to go. Does it make sense that it would apply to all boost applications, or is there more going on than I am aware of?

This is correct. You will make more power per pound of boost with a higher CR all other things equal. The big deal with lower compression is that it allows you to make more power on a given octane of fuel. You'll have to run more boost/timing to get that power though.

I'm surprised at how agressive hustler's timing table is, especially compared to mine. I'm 9.5:1, actually wanted 10:1, but weren't available in a timely manner. I was told we were at mbt for the most part throughout, no timing was pulled back out. E85, 2560R. I wanted high comp plus the smaller turbo to make it mean for autocross. I still didn't get quite the spool I wanted. If it ever goes back together I'm in for a lot more tuning.

i know im a lil late on this but you can go 20 over and still be able to use the OEM head gasket. 20 over is about as much as you would want to go on when running boost. anything more and you have less cylinder wall thickness ( no brainer )

i talked with the guy who is building my engine the other day about this stuff. he is doin a 40 over but he is going to be NA with sidedrafts, running like 13:1 compression ratio OEM style pistions and corrilo rods.

The main reason I went low comp was for headroom on the track. Its probably hurt my output below 16psi, although I make 234wtq at like 3800rpm at 11psi, but its super safe and I would do it the same way again. Its worth it for pizza-mind when I'm on the track focused on driving.

Once again, that spark table is 6-8* behind mbt at 11psi+. I'm leaving 10-15whp on the table for the sake of safety. I had it 2* back from MBT but after a friend did a rebuild from detonation in his 300ztt from heat-soak detonation, I pulled time. When you consider that we have 2-tooth CAS, no real knock control, and a stretchy timing belt, you have to be overly cautious.

You can go .030.

:facepalm:Maybe with a gigantaur amount of boost, but come on.

I would agree that it is not necessary to do it, but if anyone later needed to bore larger than .020 because of an engine failure, it is safe to do so.

In a nutshell, going with 8.6 persay vs 9.0 is just the difference between making my HP sooner on lower boost vs having a safety net and needing more boost pressure and timing to make the alotted goal? I already have ordered a snow performance water/meth kit thats going on my current motor which is stock 1.8 DD on 10psi. What im gathering from the more experienced heads on here is that water/meth on either setup would be overkill. A good question for the subject at hand is, just how much more power are people making off boost with the higher of the 2 compression ratios vs the lower of the 2? Enough to make the consideration worthwhile, so less of power off boost that I would gripe? Car is practically driven daily for 90% of its life, and 10% at the strip.

Remember that your tach reads slower than what MS logs, so where it shows 3500rpm on the log, the tach reads like 3200rpm:

http://i40.tinypic.com/wk3989.png
This is the AF parts on 8.6: compression in like 3rd gear with the CHRA/turbine leaking enough to make noise. I need to put those Nimonic bolts in or at least tighten the CHRA bolts since the first installation, lol. I saw 220-250wtq from 3500-4000rpm when tuning.

"Off boost" comparisons don't really matter because you're not concerned with power in that range when you're cruising...you just run lower kpa per wheel-speed. You're basically concerned with how soon you can hit target boost. You have good tubular manifold stuffs so you'll probably see results like what I've posted.

If you're cruising around town at less than 3000rpm then you're a tard:
http://i42.tinypic.com/121wnmb.png
At 2000rpm I'm going over 100kpa, at 2800rpm or so, the car feels like its really starting to move. At 2800rpm I'm already at 120kpa, in 2nd gear at 3200rpm (6psi/140kpa)street rubber starts to break loose on the Nitto Neogens.

I had the same worries you have currently and I'm totally happy with the performance over the entire rpm range.

The water is overkill, but adds lots and lots of safety. I'd put the money somewhere else but its not going to hurt of course.

my post was answering the dudes question with bore and headgasket, the guy that is building my motor has been racing for god knows how long and builds his own engines and has probly done about 50 or so between 1.6's and 1.8's.....im pretty sure the dude knows what he is talking about!

i didnt say you couldnt do it...but me personally, if i went overbore i wouldnt do more than .020 over for peace of mind. (i have intentions of running 17-20psi of boost threw my engine) and more eventually when i get another motor put together with a slight overbore with some H-Beams...

off topic...how much power do you have off the bottle and is your engine stock or built? i cant remember.

Search;)

Has he sonic checked the wall thickness on varying Miata blocks? If not he's guessing. When we need to know how far we can go with a particular engine we check the cylinder wall thickness at 12 spots per cylinder on all bores.

Some engines have very little meat around the bores... others like the engine in my '67 International can do rediculous overbores because it has really thick walls.

i personally plan on running higher compression prolly 10.1 but i also plan to use e85. i would stick with somewhere in the 9.1 area seems like a good medium and your power goals are by no means out there you could stick any off the shelf piston in there with less then 11.1 and you could easily meet your goals on pump gas my guess is 16psi 9.1 you will be right at that 280 area, only one way to know for sure though, also considering your power goals there no need to get crazy with the overbore you would be better off leaving some meat in there just in case you melt a piston or break a ring land you will be able to reuse the block, maybe.

ill talk to him some more this weekend about the methods he uses and what all he has done. we didnt get a chance to speak a whole lot when he dropped by to pick up the shell and engine parts.

+1

A little late to the party but as we talked about yesterday, I still think for what you are wanting to do 9.5:1 would be what you need.

Hustler's motor is overbuilt with plenty of headroom. For the goals you have it just seems like a waste to leave power on the table like that for a car that is going to see more street time than a dedicated track car.

I'm very happy with my 9.1:1 compression fwiw.
Plenty of response, plenty of headroom for timing, and low enough compression to have headroom in boost as well.

I call it the "happy middle"

If "we" ever have an affordable trans that can take the power I might put 16-20psi through it again.

Doubt your 6 speed will break on 16-20psi out of a 28.

Im starting to lean a lot more towards the 9.0-9.5 CR range, as adam mentioned, hustler's setup does seem to be built with long track sessions in mind, and in the sense that I ever thought 9.5 would be a little too much for me I do have a brand new water/meth kit in the garage ;). Recommendations from you fellas on good/trustable brands, combinations of brands? Ive seen the rods for sell over at 949 have a good price but I dont want to be lured in by "good prices" only. (no disrespect or doubt towards emilio or his parts) I've been proposed good prices on Supertech pistons and I was curious as to who actually makes the rods that 949 sells, M-tuned as well?

running mtuned rods and they are great. many on here use supertech with good results though a couple have had bad. Wiseco is usually agreed upon as making good pistons. I'd say you can't go wrong with wiseco+mtuned

If you dont mind me asking, are you running Wiseco's? A little off topic of the current rod/piston conversation, I've obviously been looking at the other aspects of the engine itself, i.e. new water pump, pickup tube/strainer, new main bearings, thrust etc etc etc....I originally had budgeted to go with a Boundary Engineering Billet oil pump, but is this necessary would I be completely fine with just a new OE Mazda pump? I've never heard of having a billet oil pump being a bad thing really, just curious to be honest? I'm also a little interested in seeing what you guys used as far as bearings for your Mains, Rod, Thrust? ACL? King? Is there a difference in quality? I know that FM sells nothing but King bearings for their bottom ends, but my experience working with local friends and engine builders a lot of Honduh guys go with ACL and swear by them? Input?

Off topic kinda but as for rods you could get away with anything as long as you have em miced and theres no out of rounds or any problems like that. i used a set of eagles in my dsm i used to have and was not pleased but i was shooting for alot more then 280hp, eagle rods seem to get a lil on edge with anything over 400hp iv seen some hold 500-600 but imo thats like making 325 on a stock bp bottom end, it will do it, for a little. btw im not sure but i belive m-tuned rods are very comparable to eagles and are beefy enough im sure to hold up to all the power you could want in a street driven miata. as for pistons i would go will je but that dosnt mean wiescos are a bad chioce either, i only say je because iv seen a good few wiescos broken at the ring lands in the ford mod motors.

I'm on OEM 9.1:1 pistons. Though I've dropped wiseco's into other cars many times and they were always great.

Some will tell you to get billet opg just cause you don't want to go back in there later if they fail. Its not absolutely necessary. Esp on a street car. Regardless of what anyone says. But a GOOD idea. Many swear by ACL bearings and I've yet to hear anything bad about them.

Might as well post the list of "planned" modifications for the top-end for you guys to oh so elegantly pick it apart and tell me whats overkill and whats not enough.

Head-
99 Head pretty much stock, just appropriately freshened up for use. This is still in the air just depending on whether or not I can find one for a good price, if not I have a 95 head laying around.

Fuel- RX7 or RC 550s whichever I can get a better price on. Still up in the air if I NEED a dual feed rail? Also, whether its dual feed or not, what type of FPR I need to go with, assuming I cant get by with a stocker? 190hp Walbro pump.

Manifold(exhaust)- Use my current ARTtech log manifold with EWG.

Manifold(intake)- Trying to get "Gotpsi" to make me one ;) if not, I guess a stocker :(

Cams-Stock

Cam Gears-Stock

Valvetrain- Planned for stock, mild work basically, 5 angle valve job but otherwise stock keepers and springs etc....

Do interject with good opinions if something needs to be done or doesnt need to be done. Good info can only help