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v8 engine bits help


wkw90

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1st I would ask which Comp Ratio it is,

being in a 90 means it could be 1 of many, if its a low Comp motor I wouldn't waste your money, and go get a 3.5 EFI one rebuild that and shove in for easy fitment of a load more BHP.

If it is a decent compression motor then fine, ....why is it being rebuilt, ......and whats the state of the insides / Bore / inside rocker covers etc etc

How much of a rebuild are we talking about here, ....and whats your budget. ?

On top of this do you want (whichever the engine used in the end) to extract any more BHP ?.

if so then now is the time to do it, but it will mean working it into the rebuild and workstream.

For a std rebuild I would always suggest

Block - chemically cleaned and a glaze bust minimum on the block

Heads - skimmed to raise comp ratio to compensate for reduced comp since composite gaskets used, possible block decked as well

Head bolts - Bin and use ARB Head studs

Vandervelt Main and Big ends bearings, to suit crank - polish or a regrind ?

Genuine Piston rings

Mod to valley area 2x small holes at front of valley to assist oil drain back and timing chain lube

Duplex Timing chain and steel gears

RTV sump on rather than a gasket

Composite head gaskets

Use all genuine seals and gaskets inc late type rubber V8 Rocker doubries :)

If heads are 2x spring per valve type - bin and fit a set of EFI heads

Frankly on a low grade V8 / light (no insult intended) I would honesty say Shimming rocker posts is OTT and will gain virtually nothing

For soft increase BHP of a carb V8 fit Piper 270 Cam and new followers

Increase needle size in carb can't remember which ones but I have it written down if you need :)

If you can afford - Block crank pistons flywhel assemble have balanced

Bottom end build.... and then add EFI top end / heads and EFI system over the carbs (yes MS even better :rolleyes: )

HTH

Nige

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1st I would ask which Comp Ratio it is,

being in a 90 means it could be 1 of many, if its a low Comp motor I wouldn't waste your money, and go get a 3.5 EFI one rebuild that and shove in for easy fitment of a load more BHP.

If it is a decent compression motor then fine, ....why is it being rebuilt, ......and whats the state of the insides / Bore / inside rocker covers etc etc

How much of a rebuild are we talking about here, ....and whats your budget. ?

On top of this do you want (whichever the engine used in the end) to extract any more BHP ?.

if so then now is the time to do it, but it will mean working it into the rebuild and workstream.

For a std rebuild I would always suggest

Block - chemically cleaned and a glaze bust minimum on the block

Heads - skimmed to raise comp ratio to compensate for reduced comp since composite gaskets used, possible block decked as well

Head bolts - Bin and use ARB Head studs

Vandervelt Main and Big ends bearings, to suit crank - polish or a regrind ?

Genuine Piston rings

Mod to valley area 2x small holes at front of valley to assist oil drain back and timing chain lube

Duplex Timing chain and steel gears

RTV sump on rather than a gasket

Composite head gaskets

Use all genuine seals and gaskets inc late type rubber V8 Rocker doubries :)

If heads are 2x spring per valve type - bin and fit a set of EFI heads

Frankly on a low grade V8 / light (no insult intended) I would honesty say Shimming rocker posts is OTT and will gain virtually nothing

For soft increase BHP of a carb V8 fit Piper 270 Cam and new followers

Increase needle size in carb can't remember which ones but I have it written down if you need :)

If you can afford - Block crank pistons flywhel assemble have balanced

Bottom end build.... and then add EFI top end / heads and EFI system over the carbs (yes MS even better :rolleyes: )

HTH

Nige

Thanks to all for advice so far .Comp ratio is 9.35 , its being rebuilt due to broken ring , block is very good , and not much in the way of sludge on rocker covers ect . Not really looking to up the power just doing as i had to . budget wise i was looking to spend around £1000 .
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Thanks to all for advice so far .Comp ratio is 9.35 , its being rebuilt due to broken ring , block is very good , and not much in the way of sludge on rocker covers ect . Not really looking to up the power just doing as i had to . budget wise i was looking to spend around £1000 .

9.35:1 is a goodie :)

Whats the timing cover off, and also the heads - please advise ?

Frankly you can buy a set of EFI heads and wiring bits bobs etc and gain BHP and smoothness,.....

In fact someone was selling an complete efi unit set for £100, look in classifieds ?

With a (sensible) budget of £1000 theres quite a lot you can do on the list above I posted

Nige

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9.35:1 is a goodie :)

Whats the timing cover off, and also the heads - please advise ?

Frankly you can buy a set of EFI heads and wiring bits bobs etc and gain BHP and smoothness,.....

In fact someone was selling an complete efi unit set for £100, look in classifieds ?

With a (sensible) budget of £1000 theres quite a lot you can do on the list above I posted

Nige The engine is from a 1984 rrc , How complex a job is fitting Efi heads ect :unsure:

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For that kind of budget I'd consider putting a chunk of it towards sourcing an EFi setup and Megasquirt'n'EDIS, that will give you greatly improved power, and driveability, plus better economy and of course water resistance.

You don't need EFI heads to run EFI, the notch for the injector spray is miniscule and I doubt it really makes a great difference. If you're bothered, get the dremel out while you're rebuilding it and make some notches.

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For that kind of budget I'd consider putting a chunk of it towards sourcing an EFi setup and Megasquirt'n'EDIS, that will give you greatly improved power, and driveability, plus better economy and of course water resistance.

You don't need EFI heads to run EFI, the notch for the injector spray is miniscule and I doubt it really makes a great difference. If you're bothered, get the dremel out while you're rebuilding it and make some notches.

What is Megasquirt'n'EDIS ?? :blink:

Paul

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^^^^^^^^

Wot they both said :)

heads wise what you have (pre 1988 EFI heads) there is little difference between them, later heads after the twin spring ones ie what you have are OK for unleaded and the main differences between these and "Efi" heads are waisted valve stems slight port changes and a tweak for where the injector goes. If your heads are in good nick and you DON'T go EFI or Megasquirt (which for £1000 rebuild would be very easy indeed and mainly nuts and bolts - and theres a load of help here should you need it) christ where was I :lol::P, oh yeah then stick with the heads you have if you keep carbs ....which I think on a £1000 budget rebuild would be a huge smahe and a missed opportuunity

If you went EFI as a 1st step to MS this would be hugely cheap, you could go either Flapper EFI (up to around late 80s) or even go for 3.9 Hotwire system (your 3.9 and 9.35:1 and skimmed heads / block wouldn't be too overfuelled IMHO, and hotwire to Megasquirt is the way to go IMHO vs Flapper to Megasquirt (although some "Northerners" do it different :P eh Rog :lol: but then again the atmospheres totally different up there ) oh and 3.9 heads ARE better than either what you have or later ones :)...buy a 3.9 turnkey maybe and rebuild this in peace and quiet over time then rip out your 3.5 and replace the entire unit easy peasy :)

Personally if you have £1000 to spend on a V8 Rebuild shoving SUs back on would be a shame

Nige :)

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I have to disagree with Nige slightly, the only real thing to choose between flapper & hotwire is the later injectors are clamp-type not hose-tail, and they don't need a resistor pack.

The flapper setup is simpler and less fussy, electrics wise, but I wouldn't keep either setup with your budget, I'd go straight to MS.

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I have to disagree with Nige slightly, the only real thing to choose between flapper & hotwire is the later injectors are clamp-type not hose-tail, and they don't need a resistor pack.

The flapper setup is simpler and less fussy, electrics wise, but I wouldn't keep either setup with your budget, I'd go straight to MS.

All me point was (oh MS Guru Fridge sir) was flapper injectors + pack etc is not as "Nice" to Megasquirt (unless of course your a Northerner :P) at a later date as a Hotwire injectors rail etc - and no resistor pack etc IF you were to do Lucas EFI 1st stage and then to Full Megasquirt - but as with you I would say grab a hotwire system and Megasquirt it as part of the rebuild, 3.5 you have now plus 3.9 heads and nice cam and a MS would be loverley :)

Nige

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