Judd

iTrader: (1)

Talked to a guy named Taylor over at Mizfit Motorsports yesterday. He gave me a new option to look into and weigh. He told me that he was doing LS1 blocks that are dry sleeved to 4.100 inches {I think} and that I could use a 4.100 crank. This would give me 433 cubic inches. At first I was wanting to use the LS7 heads. With this setup, I'm looking at around 575-600 RWHP with good reliability needed for the stuff I do {open track, autoX and hopefully 1 mile top end runs}.

But,,,, Taylor told me of another option. Use the same LS1 based 433 and use the new L92 heads and a new sheet metal intake that they are building. Supposedly the runners are fairly long for a sheet metal intake and I've seen pictures and it does look good. But looks are not what gets you power and I need to know your opinions on running a sheet metal intake on a car that will be used for autoX, open track sessions and limited street time. I also need to really talk with him a bit more on the price difference between the L92 head and sheet metal intake option and the LS7 head option. I know the LS7 heads cost alot but they are undoubtedly one of the best options out for making power. I think the price of the intake {300 bucks} and the ability to run the cheap LS2 TB will end up costing roughly the same as the L92/sheet metal intake combo. He stated that the price difference between using the LS7 head and intake vs the L92/sheet metal intake would be around 1000$. A thousand bucks could go in my pocket or to a better crank, a lighter stringer Callies crank {something like 10lbs lighter than the Eagle that would be standard}.

One thing I do like about using the LS1 based 433 will be that all my sensors will not change locations as if I were to run a LS2 or a new LS7 block. Price seems to be good and the engine will carry a 1 year warranty. I will say that Taylor takes the time to ask the questions as to how the engine will be used and any budget requirements that the customer requires. He seems to give alot of thought into what the customer needs. This is a good very good trait to have and goes a long way on making my mind up to as to what engine builder I will be using.

I'm still thinking about an option that a representative of Texas Speed and Performance threw at me. He wanted me to think about using the new LS7 block, price should be around 1000.00 to 1500.00 more than one of their current 402 {this was a pure guess on his part so please don't hold me or him to that number, could be more or less}. I like this option because of the bigger bore and the reliability afforded by using a factory block. Down sides are the before mentioned sensor problems and the price will probably be higher than the sleeved LS1 block.

Any first hand knowledge with Mizfit Motorsports or any opinions on my options would be appreciated. Could I get the power {550+/- RWHP} and reliability I want from a smaller {and hopefully less costly option} engine {lets say a 402}? I am getting ready to spend a wad of money {at least to me} and I want to make the best decision I can.

Haans249

iTrader: (24)

I talked to Taylor yesterday too. I would go for it, he gets the sleeved LS1 blocks from Steve over at race engine development and I wouldn't have anyone else do the work. I say run with it.

LSxChevelle

iTrader: (4)

how much for a block?

Judd

iTrader: (1)

Not sure on the specific price of a block.

OmniRex

iTrader: (2)

I think the Sleeved blocks from RED are about 2800

See5

iTrader: (53)

Beans is selling new LS7 blocks for ~3k.

prostock_bigblock

iTrader: (11)

I have also talked to taylor few days ago and I was very close to the 433ci, but I though about it alot and asked him if he can do me a 4.06 bore and 4 stroke on over 60 bore which well result in the 414ci big bore and he said ya we can do that. I guess no need for the extra stroke , and bigger is not always the better.

just look guys at the bigbore engines track results, Allan at Futral did an awesome work on the 396ci and the 414ci bigbores.

Greg Fell

iTrader: (9)

Don't get the LS7 block, get a resleeved ls2. They are stronger due to the liner material.

Also, IMO stick with a 4.00" stroke.

Judd

iTrader: (1)

I reckon I could do a 4.000 stroke, I would lose something like 10-11 inches {422}. But hey, 421 does have a nice ring to it,,,, 421 Super Duty. Would make for some nice fender badges.

DavidNJ

Doesn't seem like this is organized well. Signature is full of drag times, car is really a drag car, yet starting post says auto-x, open track (which are non-competitive) and street (also non-competitive). Then the engine spec adds expensive stuff (resleeving, sheet metal intakes, etc.).

For those uses the combos and places the money is being spent seem out of line. Auto-x would want a fat torque curve to minimize shifting. Open track days would want a broad flat torque curve to make it easier to drive of the corners and allow you to possibly extend the rev range to avoid shift. Street driving would favor a auto-x like torque curve. And drag racing wants power!

On the engine, sheet metal intakes are expensive. Once you are changing the crank stroke is free. So why not go 4.1? There is no rev-limit issue with the bottom end with the hydraulic roller cam. And if you are worried, just spend a few extra $$$ for better rod bolts or a lighter piston/pin.

Then I would imagine the sheet metal intake may run as much as many head/cam combos. And the wet sleeve/dry sleeve issues. The big bore LS2s are dry sleeved. And as mentioned here and on some block threads, the LS7 block is an inexpensive big bore LS2. The aftermarket sleeves are better.

Now, back to your intended purposes. Throttle response and performance would be best with an ITB. And the LS1 has a nice readily available and wide used ITB at relatively modest cost...the Harrop. On top of that, the Harrop will generate far more oos and ahs at a road course than a sheet metal intake. For your application that seems like a first move.

Then, a set of AFR 205s or ET 215s. On your 347, this combo should get you in the 10s at the drags and produce a nice, drivable engine on auto-x and open track events.

If you are making a 4x4.1, then one size larger.

Or if, going to a 4" bore, an ET LS7/4 with an LS7 intake. The smaller valves fit the 4" bore, and the intake and the head flow very well. With a

thinkBIG

Was there more David?

Judd

iTrader: (1)

I go drag racing a couple of times a year. When I do, I take all my vehicles. That is the reason for all the 1/4 mile times. It is also the universal yard stick for performance and that is why I have the times in my sig. I will also be running 1 mile top end events at Maxton N.C., need power for that. I see nothing wrong with the organization, I just use my car for alot of different stuff but I do more AutoX and open track stuff than drag racing. The car is most definetly not a drag car. Take a look at my mods if you want. I stated my intended uses for the car and they have not changed.

Plenty of people here will drop 5-6K$ on turbos or a blower alone {not getting into the engine at all} and all they do is a bit of drag racing and playing around. So far I'm looking at 10K$ for a complete engine with intake and injectors, not that out of line when you conceder that if I buy a stock CI motor with a good bottom end, add heads, intake and TB I will still be looking at something in the 6-7K$ dollar range and will be getting no more than around 475RWHP and I honestly think that a 347 making that much power will need quite a large cam and a large set of heads. I think that will lead to a fairly peaky engine that is not what I wanted. Displacement and a moderate cam usually gives a nice flat power curve which is what I'm looking for.

The sheet metal intake is actually not too bad in price {around 1000$}and uses a GM 90mm TB. A LSX is around 800$ and uses a pricey TB so the sheet metal intake while definitely costing more, is not that much more than any other option I think. What's the cost on the Harrop unit, bet it's way up there? I think that would break any perceived budget as much or more than a stroker crank or a sleeved block. I really don't think the cost/power ratio would be all that good on something like that. If I'm wrong on the price issue of that intake combo {the Harrop} then let me know and I will look into it. As far as the ohs and ahs generation of an intake, it's the last thing on my mind. I wanted to run a LS7 intake but due to having to run LS7 heads, it would be a costlier option. As far as I know, the LSX would probably be the least costly option {not by much though, 300$ or so} but it will undoubtedly be a restriction on a big motor I would think. Correct me if I'm wrong on that.

The only thing I'm worried about with the 4.1 inch stroke is the longevity of it. I'm worried that the pistons might partially come out of the sleeve at the bottom of the stroke and present a piston rocking problem that would damage the skirts. I'm worried about rod ratios also since this motor will be run hard for 30 minutes at a time. I'm worried that a 4.1 stroke is not what I need for this motor. Any comments on this particular area of my build. If I'm worrying about a non-issue, I would just as soon have the extra displacement since it really want cost any more at this point.

I'm also wondering about the difference in the LS7 head/intake combo vs the L92 head/sheet metal intake combo. The L92 combo is definetly cheaper but is it cost effective? The builder feels confident that my HP goals are easily achievable with the L92 stuff so why not use it and spend the money elsewhere? Any comments on this issue?

Like I said, I'm sorry for the book of questions here but I'm just wanting to make the best decision I can on this and getting different opinions on specifics is the best way I think and this seems to be one of the best places to get those opinions.

DavidNJ

Hondas have a worse rod/stroke ratio than that.

This thread--https://ls1tech.com/forums/showpost.php?p=4761095&postcount=300--shows a 346 (with AFR 225s) making 460hp with a broad torque curve and a 224/228 (actually 223/227) cam. A Harrop intake would have increased its throttle response and maybe peak power. Moreover, torque is within 10% of peak from 3500-6500.

Judd

iTrader: (1)

For some reason the thread link doesn't work for me.

Bring the Noise

Hmmm What about using a L92 Block with a larger crank and it's ECU and wiring harness.

With a little adjustment the Cam Phaser could be set up to work and allow a flat torque curve (by adjust the cam at certain rpm ranges) - Auto X settings. Or set the ECU to lock the Phaser inplace giving a fat torque down low - Open Track Events.

Biggest things to using the L92 would be
A motor and ECU - who's got em and how much to get one loaded with the 4in crank and have the heads port'd and Polish'd? And who's got the low profile manifold?
Programing the ECU - I don't know if LS*Edit has support for the L92's yet and I don't think the latest version of HP Tuners includes the L92 or the L76 (but I could be mistaken).

Bring the Noise

The Harrop Hurricain is around $4000 to $5000 just a heads up. It's Pretty, but not that Pretty.

The L92 heads still have a 15 degree valve angle. With them ported you should be able to achieve what your looking for with a 400+ cu motor.

I still like the thought of GM's Cam Phaser to adjust the cam degreeing...
I wonder if any of the GM backed racing team's have used it yet?

the Phaser basicly give's the motor the ability to create more torque in the low end and create more hp in the upper end by adjust the cam's location (advanced in low rpm and retarded in the upper rpm I think is how it goes... brain's not working well right now though).

Just remember there are 2 versions of the F.A.S.T. intake. One uses a 76mm TB (stock LS1 size) and the other uses a 90mm throttle body. So you may need to go with a BBK or F.A.S.T. 90mm TB instead of the stock 76mm units to achieve your goals.... Misfit's would probably be able to tell ya what size there manifold is going to take.

Heck a Hand Fab'd L92 manifold for $1000 isn't to bad if it outflow's a F.A.S.T. as the ported L92's should flow close to what a set of high end ETP's (just a guess on this one looking at the stock flow spec's of the L92's).

I still think a L92 Block with it's 4.060 and a 4.00 crank would be a nice choice (and allow you to spend a little more on the Callies crank).

Just things to think about...

If you look at the L92 with the Cam Phaser component you will need to make sure the cam is not to large or close on lobe seperation (as the cam phaser will adjust the cam's degree and could cause PVT issue's if no R&D is done on the front end). But a smart engine builder will look at how far the phaser adjust's the degreeing and work the components together.

If the cam and piston's are designed to work with the cam phaser then there wouldn't be any need of worry about PVT (that is if the rest of the motor was built correctly).

I'm hoping SDPC or someone will put together a L92 shortblock with the Callies 4in soon (hell what am I talking about I'm still waiting on my edelbrock GTO headers that I ordered through SDPC)....

Judd

iTrader: (1)

Thanks for the Harrop intake price,,,,, too much, way too much for me considering the small gain. I don't think I'll be considering a LSX if I get this engine from Mizfit, I will either go with the L92 heads and the sheet metal intake or I will run LS7 heads and the LS7 intake. The LSX is just too expensive when you factor in that it is still represents a restriction on a bigger engine.