Fuel and Headgasket.
Thread Starter
Teching In
Joined: Feb 2014
Posts: 10
Likes: 0
From: Glasgow, Scotland
Fuel and Headgasket. I have a few questions I've been unable to get a clear answer on, first is when you guys talk about pump fuel, what octane rating is the fuel in USA and is it measured in RON or MON, E85 isn't available here(Scotland) so that's not a realistic option.
Second question is to do with compression ratios, if I was needing a slightly higher compression that the next cc of pistons was too much for would it be better to get the heads skimmed or to use a thinner gasket. Would skimming the heads increase the chance of them lifting and is a thinner head gasket considered any stronger or weaker than stock thickness?
Last question for now would be if you were building a iron blocked engine with aftermarket rods and pistons with a air to air intercooler to run on 99 octane fuel(RON) what compression ratio would you aim for and would you choose a 5.3 or 6.0 and why?
Second question is to do with compression ratios, if I was needing a slightly higher compression that the next cc of pistons was too much for would it be better to get the heads skimmed or to use a thinner gasket. Would skimming the heads increase the chance of them lifting and is a thinner head gasket considered any stronger or weaker than stock thickness?
Last question for now would be if you were building a iron blocked engine with aftermarket rods and pistons with a air to air intercooler to run on 99 octane fuel(RON) what compression ratio would you aim for and would you choose a 5.3 or 6.0 and why?
9 Second Club
Joined: Nov 2003
Posts: 13,616
Likes: 185
From: Norn Iron
US PON is a mix of RON/MON
Basically US 93 PON is about same as our UK 98 RON
And as you dont state type of boost, power, boost targets, IC efficiency, application, form of fuel/spark control etc etc...
Asking what compression is a VERY open ended question.
As for engine size, again cost vs application
Do you need the low rpm torque a bigger motor will offer ?
You need to specify goals before answers can be given
Basically US 93 PON is about same as our UK 98 RON
And as you dont state type of boost, power, boost targets, IC efficiency, application, form of fuel/spark control etc etc...
Asking what compression is a VERY open ended question.
As for engine size, again cost vs application
Do you need the low rpm torque a bigger motor will offer ?
You need to specify goals before answers can be given
Thread Starter
Teching In
Joined: Feb 2014
Posts: 10
Likes: 0
From: Glasgow, Scotland
I'd never heard of PON before.
My question on compression wasn't what compression it was more about which is the preferred method of raising and which method, will skimming the heads increase the chance of them lifting and is a thinner gasket a bad idea or not. Obviously I will buy the pistons that get me nearest to my intended compression ratio, and I might not need to do anything, just trying to get a better idea of what i'm going to need or have to do.
Type of boost will be a turbo, don't know which turbo yet, power and boost targets are unknown, basically what I can safely get away with. intercooler efficiency is also an area I'm not sure of yet, I don't know which intercooler I will be using. Fuel and spark control will be from the stock ecu for now.
The question about the size of the motor was purely about strength. Cost is important to me I'm not on a huge budget but I'm also not in a huge rush to get it all done. I want to get the engine choice right first time as being in the UK stock engines are rare as it gets. I've read a lot of threads on here with people saying just run the bottom end stock and when it blows just buy another stocker but that's not a practical option over here.
Its going in a Nissan S13 with a th400 behind it, mainly getting built for the strip but it will see a fair bit of street use(not a drift car)
My question on compression wasn't what compression it was more about which is the preferred method of raising and which method, will skimming the heads increase the chance of them lifting and is a thinner gasket a bad idea or not. Obviously I will buy the pistons that get me nearest to my intended compression ratio, and I might not need to do anything, just trying to get a better idea of what i'm going to need or have to do.
Type of boost will be a turbo, don't know which turbo yet, power and boost targets are unknown, basically what I can safely get away with. intercooler efficiency is also an area I'm not sure of yet, I don't know which intercooler I will be using. Fuel and spark control will be from the stock ecu for now.
The question about the size of the motor was purely about strength. Cost is important to me I'm not on a huge budget but I'm also not in a huge rush to get it all done. I want to get the engine choice right first time as being in the UK stock engines are rare as it gets. I've read a lot of threads on here with people saying just run the bottom end stock and when it blows just buy another stocker but that's not a practical option over here.
Its going in a Nissan S13 with a th400 behind it, mainly getting built for the strip but it will see a fair bit of street use(not a drift car)
9 Second Club
Joined: Nov 2003
Posts: 13,616
Likes: 185
From: Norn Iron
PON is Posted or Pump Octane Number
I guess Wiki will always explain better
http://en.wikipedia.org/wiki/Octane_rating
Yip, was over at Crail in November, but I went to adjust a rear shock early in the day and the damn adjuster fell out in my hand emptying it's oil everywhere ! lol
That cut things short. But yes I've had various LS builds in my car for over 10 years now.
If you're concerned about skimming the heads, heads lifting and wanting to raise the CR....
I'd have to ask, why are you wanting to raise the CR in the first place and from what to what ?
Strength wise the junkyard 5.3's are proving their worth, but again it depends how hard you want to push. Even standard 6.0's are making big numbers and hanging together. But there are many model years too
Are you intending to use a standard engine, or change internals ? Iron or alloy block ?
With an auto, and I suspect the vehicle isnt that heavy...engine size really wont matter so much. But it can be nice to have the larger motor.
If you could pick a really cheap alloy 5.3 I'd go with that purely on cost, but as you say, they're easy come by in the US, not so in the UK.
But unless aiming for well over 1000hp, I just cant see the point in the weight penalty of iron, unless you get the engine really really cheap.
I guess Wiki will always explain better
http://en.wikipedia.org/wiki/Octane_rating
Yip, was over at Crail in November, but I went to adjust a rear shock early in the day and the damn adjuster fell out in my hand emptying it's oil everywhere ! lol
That cut things short. But yes I've had various LS builds in my car for over 10 years now.
If you're concerned about skimming the heads, heads lifting and wanting to raise the CR....
I'd have to ask, why are you wanting to raise the CR in the first place and from what to what ?
Strength wise the junkyard 5.3's are proving their worth, but again it depends how hard you want to push. Even standard 6.0's are making big numbers and hanging together. But there are many model years too
Are you intending to use a standard engine, or change internals ? Iron or alloy block ?
With an auto, and I suspect the vehicle isnt that heavy...engine size really wont matter so much. But it can be nice to have the larger motor.
If you could pick a really cheap alloy 5.3 I'd go with that purely on cost, but as you say, they're easy come by in the US, not so in the UK.
But unless aiming for well over 1000hp, I just cant see the point in the weight penalty of iron, unless you get the engine really really cheap.
Thread Starter
Teching In
Joined: Feb 2014
Posts: 10
Likes: 0
From: Glasgow, Scotland
Again thanks for the reply Stevie. We loaned the guys I think you were with at Crail some tools, they had the quick Legacy. I was there helping my friend with his wee Toyota.
The question about raising the compression came from me looking at Wiseco pistons for the 5.3, as standard they give you 9:1 which I thought be on the low side.
Pretty sure I'll go for an iron block purely in the interest of strength and it I think I'm going to go for a 5.3 for now, the price of the 6.0's seems to have jumped quite a bit since I started looking into this a year or 2 ago. Wouldn't be so bad buying just a longblock but I figure I should be buying a complete dropout as I'm starting with nothing anyway.
The question about raising the compression came from me looking at Wiseco pistons for the 5.3, as standard they give you 9:1 which I thought be on the low side.
Pretty sure I'll go for an iron block purely in the interest of strength and it I think I'm going to go for a 5.3 for now, the price of the 6.0's seems to have jumped quite a bit since I started looking into this a year or 2 ago. Wouldn't be so bad buying just a longblock but I figure I should be buying a complete dropout as I'm starting with nothing anyway.
9 Second Club
Joined: Nov 2003
Posts: 13,616
Likes: 185
From: Norn Iron
Yea cool, a bloody rear driveshaft nut came loose on it !!
We'll hopefully get back over again this year once or twice. Days like that though are better as they're quieter so there are no silly queues.
But talk on FB suggests this year may well be the last year for Crail, as there are rumours about development. Hopefully not the case though
I've never had iron on mine, and have no intentions of using an iron block, alloy will cope with a lot of power, even more so in 5.3 format.
I'm sure many will say a higher CR is better....but mine's around 9.0:1 too. What you will gain in safety margin will far outweigh what you may gain in power from a higher CR.
And with the lower...any power can be recouped with a little more boost/timing
Whereas if you aim for a higher CR and end up knock limited...without better fuel etc, then you have no way to push harder.
And would agree, get as complete a package as possible for any swap. I'd be hunting down an alloy 5.3 though unless an iron version was ridiculously cheap.
We'll hopefully get back over again this year once or twice. Days like that though are better as they're quieter so there are no silly queues.
But talk on FB suggests this year may well be the last year for Crail, as there are rumours about development. Hopefully not the case though
I've never had iron on mine, and have no intentions of using an iron block, alloy will cope with a lot of power, even more so in 5.3 format.
I'm sure many will say a higher CR is better....but mine's around 9.0:1 too. What you will gain in safety margin will far outweigh what you may gain in power from a higher CR.
And with the lower...any power can be recouped with a little more boost/timing
Whereas if you aim for a higher CR and end up knock limited...without better fuel etc, then you have no way to push harder.
And would agree, get as complete a package as possible for any swap. I'd be hunting down an alloy 5.3 though unless an iron version was ridiculously cheap.
Trending Topics
Thread Starter
Teching In
Joined: Feb 2014
Posts: 10
Likes: 0
From: Glasgow, Scotland
Next time your at Crail I'll come and get a look at your car if that's ok. Should be there quite a bit this year with a couple of friends who's cars I help with. I've been hearing the same thing about Crail, funny as they always use the excuse about the land being protected by Historic Scotland or something like that as the reason the don't improve on the strip or even smooth out the return road. Rumours keep doing the rounds that the owners of Driftland are going to build a proper dragstrip but I've never heard anything official on it. They supposedly have the land, but the same thing happened on the west coast a few years ago.
I'll maybe just go with 9.0:1, I like the sound of safe and as you said I can always add more boost and or timing.
The iron engines are a lot cheaper than the complete alloy versions, I think with the budget i'm on irons going to be the winner. I'm not to worried about how it handles with the extra weight up front as I've another one that's more of a track day car that's staying Nissan powered for now.
I'll maybe just go with 9.0:1, I like the sound of safe and as you said I can always add more boost and or timing.
The iron engines are a lot cheaper than the complete alloy versions, I think with the budget i'm on irons going to be the winner. I'm not to worried about how it handles with the extra weight up front as I've another one that's more of a track day car that's staying Nissan powered for now.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo 9 Second Club
Joined: Nov 2003
Posts: 13,616
Likes: 185
From: Norn Iron
According to the FB page, even Willie had been in discussions about development so it isnt a new thing, and obviously he was the main driving force behind Crail Thrash.
But obviously money talks whether protected or not, they always find ways around it.
I cant imagine in this day and age anywhere building a new strip. I just dont see how it would ever be financially viable as there's no way it'd ever turn a sensible profit...of any profit at all.
There was talk as you say about a couple of venues being resurrected in Scotland I think, and there was similar talk over here about different motorsport tracks and venues...none of them ever happened or got beyond some drawings and rumours.
Just a sign of the times really.
Only other venue I've heard of in Scotland...sort of, is I think once a year there's an even up in Stornoway where they close the airport and run there. Not really very local though, but would be cool for a road trip some day
But obviously money talks whether protected or not, they always find ways around it.
I cant imagine in this day and age anywhere building a new strip. I just dont see how it would ever be financially viable as there's no way it'd ever turn a sensible profit...of any profit at all.
There was talk as you say about a couple of venues being resurrected in Scotland I think, and there was similar talk over here about different motorsport tracks and venues...none of them ever happened or got beyond some drawings and rumours.
Just a sign of the times really.
Only other venue I've heard of in Scotland...sort of, is I think once a year there's an even up in Stornoway where they close the airport and run there. Not really very local though, but would be cool for a road trip some day